Building a Simple App with Kairos Facial Recognition API in Javascript

What is Facial Recognition?

Facial recognition is a system of processes or algorithms that translates the characteristics of a face from a digital source into numbers that can be used to later identify the face.

Face detection, and the ethics surrounding the practice, has become an important topic in tech and a valid topic in political discussions. Facial recognition has a few different names (i.e image processing, computer vision) and falls into the larger category of artificial intelligence and machine learning. It has grown hand-in-hand with the rise of data science practices, the popular programming language Python, and the aggregation of massive data stores. One of the data science techniques that can be used to identify a face is a neural network.

Neural networks are a bit beyond the scope of this article, but we should have the general idea before using the API. If we were to submit an image to a neural network it would be processed at different levels. The network would be trying to answer a question, for example, “Is there a face in this image?“. Sections of the photograph would be selected and the system would gather information on whether the lighting and colors reveal edges, curves—or an object. This information means nothing unless the system has something to compare it with.

The system, hypothetically, has patterns of data points that have been positively identified as resembling faces. If the data points collected from sections of the submitted photograph are consistent with the data point patterns of faces, then the neural network can answer, “Yes, there is a face in this photograph!”, or, “I don’t think there is anything here”. This is typically done with ‘confidence intervals’ that are between 0 and 1. We will be able to glimpse some of these data points in the response object from the Kairos Facial Recognition API.

Kairos API

In using the Kairos API, we remove the need to build our own face database and understand complicated statistical algorithms. This can save a company a lot of time and money. In addition, Kairos is simple. I was able to grasp the use cases for the nine endpoints listed in the dashboard with ease.

With Kairos, images that contain faces (that you hope to identify later) are put into galleries. For example, if I had three pictures of three different friends, I would add each of them to the gallery ‘Friends’. Later, I could use different endpoints (‘/recognize’, ‘/verify’) to identify my friends in group pictures or different individual pictures. I could check all my galleries, or submit an image and have the API search a specific gallery.

Kairos only accepts a few parameters across it’s endpoints:

  • “image”
  • “gallery_name”
  • “subject_id”
  • “selector”

This means that we can quickly build uncomplicated HTTP requests.

Furthermore, the “image” parameter accepts a publicly accessible URL, file upload or base64 encoded photo.

I hope to show you how simple it is to create galleries, upload pictures, and recognize images in the example javascript app below. We will build a ReactJS frontend that allows users to upload images to either the ‘friend’ gallery, or the ‘foe’ gallery. Next, the frontend will send the image data to our node.js backend that will fire off the request to the Kairos API for processing and return the data to the user in the frontend. We will enroll subjects in both galleries, then identify our friends and foes in later images.

Connect to the Kairos Face Recognition API

How to Build a Facial Recognition App with JavaScript

Prerequisites

In order the complete the application there are a few items that need to be completed.

First, you will need a RapidAPI account. Second, after setting up an account you will need to subscribe to the Kairos API. You can’t beat the basic subscription. We get 1000 API calls a month, and after that, it’s $0.0001 each request. That will be plenty for us in this example. Next, make sure that you have:

  • Node >= 8.10 and npm >= 5.6 on your machine
  • some familiarity with how to open and use a command-line tool
  • an internet connection
  • a code editor (I recommend VS Code)
  • some familiarity with Javascript, specifically React and Node.
  • I will be using the bash terminal on macOS but most of the commands should be the same with the Windows command prompt.

We will also need React >=16.8.0, however, if you are following the instructions, we will be downloading an acceptable version in the process.

Steps

Setting Up the Project

1.Open up a new terminal

2. Navigate to a good directory using cd.

3. Make a new directory named face_recognition:

mkdir face_recognition

4. Move into that directory:

cd face_recognition

5. Run npx create-react-app client. Npx is a program that ships with npm. We are creating a new React project using the popular project Create React App and placing it in a folder named ‘client’. After a few minutes, you should see the new folder appear in face_recognition.

6. In face_recognition, make a new directory server and cd into the empty folder.

7. Initialize a new npm module:

npm init -y

The -y flag fills out the information that we would be prompted to answer that describes the package. Filling out this information is unnecessary in this tutorial. We now have our front end folder and our server folder ready for installations and modifications!

Set Up Express Server

1.Open up your code editor. I am using VS Code with the command line interface installed, so if I am in the root of our project (face_recognition) I can execute code . and VS Code will open in that directory. Keep the terminal open because we will be installing packages soon.

2. In the terminal, navigate into server and install express and dotenv:

npm install express dotenv --save

We will use express as our web application and dotenv to store our RapidAPI key so we don’t accidentally commit it to a repository. We will not be pushing the code base to Github, but it’s a good habit to have.

2. Install nodemon for development:

npm install nodemon --save-dev

3. Add a dev script to server/package.json that will make it easier for us to use nodemon in development.

// server/package.json

{
  ...
  "scripts": {
    "start": "node server.js",
    "dev": "nodemon server.js -e js",  // our new script
    ...
}

4. Make a new file server.js in the folder server. Add the below code to it.

// server.js
const express = require('express');

//const path = require('path');

// Import routes

// Create App
const app = express();
const port = process.env.PORT || 3001;

// Adds a parsed json body object to req
app.use(express.json({ limit: '10000kb' }));

// Future route
// app.use('/api/', router);

// DEPLOYMENT: for express to find static assets in the React build
// app.use(express.static(path.resolve('client', 'build')));

// DEPLOYMENT: so express can return an actual webpage
// app.get('*', (req, res) => {
      res.sendFile(path.resolve('client', 'build', 'index.html'));
// });

// console.log that your server is up and running
app.listen(port, () => console.log(`Listening on port ${port}`));

The majority of the code is commented out because it’s not time for it to be used. The code blocks that are commented out and labeled “DEPLOYMENT” will not be used in this app, but would be used if you were to deploy to a server. They allow the express application to find the React frontend and serve static files.

In this file, so far, we are creating the express app, adding JSON parsing middleware, and telling the app to listen for requests on port 3001. Easy enough! Next, we’ll go to the front end for general set up, and make sure that it can communicate with our backend.

Set Up Frontend

In the client folder there is another package.json file. However, it has different contents and is not related to the package.json in the server folder because, although our client and server folders are in the same directory, they are separate entities.

What we are going to do is open up a path of communication between the two folders by adding a directive in package.json. The directive will proxy the requests that we make on the frontend to port 3001 (the port we specified in the express application).

1.Add proxy to front-end

// client/package.json

{
  ...
  },
  "proxy": "http://locahost:3001"
}

Now, when we send requests on the front end to the root url they will be received by our backend.

2. We are going to do some basic clean up in our client folder and install a few packages that we will use later. Open App.css and fill it with the code below:

.App {
  display:flex;
  flex-direction: column;
  min-height: 100vh;
}

.App-header {
  background-color: #282c34;
  min-height: 300px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  font-size: calc(10px + 2vmin);
  color: white;
}

main {
  flex-grow: 1;
  text-align: center;
  padding: 25px;
}

footer {
  padding: 2px;
  min-height: 100px;
  display: flex!important;
  flex-direction: column;
  justify-content: center;
  background: #EEEEEE;
  font-size: small;
  text-align: center;
}

header {
  padding: 25px;
}

Explaining the CSS is beyond the scope of the article. The code above will give us a nice layout to build our app.

3. Create React App ships with some example content that is displayed in App.js, but we are going to replace it with our own set up. Open App.js and add the code:

import React from 'react';
import './App.css';

function App() {
  return (
    <div className="App">
      <header className="App-header">
        <h1>Friend or Foe</h1>
      </header>
      <main>
        
      </main>
      <footer>
        Page created by yournamehere
      </footer>
    </div>
  );
}

export default App;

4. We are almost ready to fire up our app. Before we do that, let’s install a few packages that we are going to use extensively for styling. Double check that your terminal is in the client folder before executing the next command.

npm install react-bootstrap bootstrap

5. Import the bootstrap CSS into the page and add content to the `` tag of our app.

// App.js
...
import 'bootstrap/dist/css/bootstrap.min.css'
import { Container, Row, Col } from 'react-bootstrap'

function App() {
  return (
    <div className="App">
      ...
      <main>
        <Container>
          <Row className="justify-content-md-center">
            <Col md="6">
              <h1>Test person form</h1>
            </Col>
            <Col md="6">
              <h1>Add person form</h1>
            </Col>
          </Row>
        </Container>
      </main>
      ...
    </div>
  );
}

export default App;

We are now ready to start our application and see what we are working with!

5. In client run npm start. The development server will start up and our app will be viewable at http://localhost:3000.

Your page should look like this:

This is image title

Build Input Form

As can be seen from the headings, we are going to have a form where an image is tested for recognition and another form where we add images to galleries. This is going to be the same ReactJS component, but we are going to add conditionals that decide how the component is rendered. We are going to use React hooks to store our form data.

1.Make a directory in the src folder named components. Inside that folder create another folder ImageUploadForm. Inside ImageUploadForm create two files;

  1. ImageUploadForm.js
  2. ImageUploadForm.module.css

In ImageUploadForm.js we are going to start to build a form, using the react-bootstrap library, that has three inputs. These inputs correspond to three of the basic parameters I mentioned earlier (gallery_name, image, subject_id).

2. Add the code below that structures our form.

import React from 'react'
import { 
    Form 
    } from 'react-bootstrap'
import classes from './ImageUploadForm.module.css'

const ImageUploadForm = (props) => {
    return (
        <Form className="my-4">
            <Form.Row className="text-left">
                select gallery
            </Form.Row>
            <Form.Row className="text-left">
                enter subject name
            </Form.Row>
            <Form.Row>
                select or input image
            </Form.Row>
        </Form>
    )
}

export default ImageUploadForm

3. Import our new form into App.js and add it to our columns.

// App.js
...

import ImageUploadForm from './components/ImageUploadForm/ImageUploadForm'

...
// App.js
...
import ImageUploadForm from './components/ImageUploadForm/ImageUploadForm'

...
   ...
      <main> 
        <Container> 
          <Row className="justify-content-md-center"> 
            <Col md="6"> 
              <h1>Test person form</h1>
              <ImageUploadForm />
            </Col> 
            <Col md="6"> 
              <h1>Add person form</h1>
              <ImageUploadForm /> 
            </Col> 
          </Row>
        </Container>
      </main>
   ...
...

That shouldn’t change the look of the app, but it will when we start adding inputs.

The first input we are going to add are radio buttons that select the gallery name. Our app is going to have two galleries: “friend” and “foe”.

We will need to import the { useState } hook at the top of the page and declare our hook at the top of the components. If you are new to hooks, they are essentially a simple way to hold and change state in a component.

4. Replace “select gallery” with the code below.

// Image UploadForm.js 
import React, { useState } from 'react' 
... 

const ImageUploadForm = (props) => { 
   let [galleryName, setGalleryName]= useState('friend') // set starting value to 'friend'
      ...
         ...
            ...
                <Form.Group>
                    <Form.Label>Gallery</Form.Label>
                    <Form.Text className="text-muted">
                        Select upload gallery.
                    </Form.Text>
                    <Form.Check 
                        type="radio"
                        label="Friend"
                        checked={galleryName === "friend"}
                        onChange={() => setGalleryName("friend")}
                        />
                    <Form.Check 
                        type="radio"
                        label="Foe"
                        checked={galleryName === "foe"}
                        onChange={() => setGalleryName("foe")}
                        />
                </Form.Group>
            ...
         ...
      ...
   ...
}

Next, we are going to do something very similar to store the subject_id (name) variable, but we only want to show this input if we are adding someone to a gallery. Therefore, we will pass a ‘prop’ to each form that identifies which endpoint the form will be utilizing.

If we are testing a person we will set the endpoint prop to ‘recognize’, and if we are adding a person we will set the endpoint to ‘enroll’.

5. In App.js two variables above the App() function:

const recognize = "recognize"

const enroll = "enroll"

6. Add the prop ‘endpoint’ to each upload form. Give the ‘Add person’ form endpoint prop a value of {enroll} and the ‘Test person’ endpoint prop a value of {recognize}. It may seem weird to have variables that match their own string value, but we are going to use these values again and want to avoid hard coding those strings in four different places.

// App.js
...

const enroll = "enroll"
const recognize = "recognize"

...
   ...
      ...
         ...
            <Col md="6"> 
              <h1>Test person form</h1>
              <ImageUploadForm
                endpoint={recognize}
              />
            </Col> 
            <Col md="6"> 
              <h1>Add person form</h1>
              <ImageUploadForm
                endpoint={enroll}
              />
            </Col>
         ...
      ...
   ...
...

Back in ImageUploadForm.js we can check this prop and if it equals ‘enroll’ then we will display the ‘Name’ input.

7. Add the ‘Name’ input with a conditional to ImageUploadForm.js in replace of the row that has ‘enter subject name’. Remember to add the hook that declares the variable and set function.

...
   ...
      ...
         ...
            {props.endpoint === 'enroll' ?
            <Form.Row className="text-left">
                <Form.Group>
                    <Form.Label>Name</Form.Label>
                    <FormControl
                        type="text"
                        placeholder="Subject name"
                        onChange={(e) => setName(e.target.value)}
                        value={name}
                        required
                    />
                </Form.Group>
            </Form.Row>
            : null
            }
         ...
      ...
   ...
...

After adding the conditional input row your forms should look like this:

This is image title

The last input is the image input, but it will require a little more work.

Adding the Image Input

The image input comes in a few different forms. The Kairos API “image” parameter accepts a publicly accessible URL, file upload or base64 encoded photo. Our form is going to take an image upload, translate it to base64, and submit that string, or it will accept the URL string and submit that as the image parameter.

Therefore, we need two different inputs. In order to accomplish this, we are going to create two tabs in each column, one for URLs, and one for image uploads. We will then pass another prop specifying whether the form accepts ‘file’ or ‘text’.

1.Import the Tab component from react-bootstrap and duplicate the image forms. Each column should have two Tabs, two ImageUploadForms, and one form should have a prop type='file' while the other has a prop type='text'. We are going to add a placeholder prop for our text forms. App.js should have the following code:

import React from 'react'
import './App.css'
import 'bootstrap/dist/css/bootstrap.min.css'
import { Container, Row, Col, Tab, Tabs } from 'react-bootstrap'
import ImageUploadForm from './components/ImageUploadForm/ImageUploadForm'

const recognize = "recognize"
const enroll = "enroll"

function App() {
  return (
    <div className="App">
      <header className="App-header">
        <h1>Friend or Foe</h1>
      </header>
      <main>
        <Container fluid>
          <Row className="justify-content-md-around">
            <Col md="5">
              <h2>Test Person</h2>
              <Tabs defaultActiveKey="upload" id="uncontrolled-tab-example">
                <Tab eventKey="upload" title="Upload">
                  <ImageUploadForm
                    label="Select Image to Test"
                    type="file"
                    endpoint={recognize}
                  />
                </Tab>
                <Tab eventKey="url" title="URL">
                  <ImageUploadForm
                    label="Enter Image URL to Test"
                    type="text"
                    placeholder="Image address URL"
                    endpoint={recognize}
                  />
                </Tab>
              </Tabs>
            </Col>
            <Col md="5" className="bg-light">
              <h2>Add Person</h2>
              <Tabs defaultActiveKey="uploadAdd" id="uncontrolled-tab-example">
                <Tab eventKey="uploadAdd" title="Upload">
                  <ImageUploadForm
                    label="Select Image to Add"
                    type="file"
                    endpoint={enroll}
                  />
                </Tab>
                <Tab eventKey="urlAdd" title="URL">
                  <ImageUploadForm
                    label="Enter Image URL to Add"
                    type="text"
                    placeholder="Image address URL"
                    endpoint={enroll}
                  />
                </Tab>
              </Tabs>
            </Col>
          </Row>
        </Container>
      </main>
      <footer>
        Page created by yournamehere
      </footer>
    </div>
  );
}

export default App;

Now, you should be able to switch back and forth between the ‘Upload’ tab and the ‘URL’ tab. Nothing changes in the form yet because we have not added the image input.

2. In ImageUploadForm.js add the image input where it says ‘select or input image’. We will also need to import Button from react-bootstrap and create the file variable in state.

...
import {
   Form,
   Button,  //import button
   FormControl ) from 'react-bootstrap'                
   ...
	 
const ImageUploadForm = (props) => {
   ...
   let [file, setFile] = useState(null)  // add file to state
      ...
         ...
            ...
               <div className="input-group d-flex justify-content-center mb-3">
                    <div className="input-group-prepend">
                        <Button type="submit" variant="primary">Upload</Button>
                    </div>
                    <div className={props.type === 'file' ? "custom-file" : ''}>
                        <label className={props.type === 'file' ? "custom-file-label text-left" : 'text-center'}>{!file ? props.label : file.name}</label>
                        <input 
                            required
                            type={props.type}
                            className={props.type === 'file' ? "custom-file-input" : "form-control"}
                            placeholder={props.placeholder}
                            />
                    </div>
                </div>
            ...
         ...
      ...
   ...
}

You can now see that the input changes between a text image upload and a file image upload. This is because we are changing values in the code based on the props that the component is being passed.

Add Preview

It would be nice if our users could see the image that they are about to upload. Currently our image input isn’t added to state. We are going to build a file staging function that operates conditionally:

  1. If the image is uploaded, the file is converted to base64 and a local URL is created for the preview
  2. If the image input is a URL the string then we set the appropriate variables to the string

In addition, we will have an `` element that is waiting to receive a value for it’s src attribute.

1.In ImageUploadForm.js add another value to the state:

let [fileSrc, setFileSrc] = useState('')

2. Import the useCallback hook at the top of the page next to useState

import React, { useState, useCallback } from 'react'

The useCallback hook memoizes the function. This is beyond the scope of the article, and might be a little unnecessary for such a small app and function.

3. Add the fileStaging function to ImageUploadForm.js.

...
    const fileStaging = useCallback((e) => {
        if (props.type === 'file') {
            setFile(e.target.files[0])
    
            let reader = new FileReader();
    
            try {
                reader.readAsDataURL(e.target.files[0])
            } catch (e) {
                setFileSrc('')
            }
    
            reader.addEventListener("load", function() {
                setFileSrc(reader.result)
            }, false)
        } else {
            setFileSrc(e.target.value)
        }
    }, [props.type])
...

3. Add the image preview to the bottom of the form.

...
   ...
      ...
         ...
            <h2>Image Preview</h2>
            {fileSrc ? <figure><img className={classes.Image} alt="" src={fileSrc} /></figure> : <p style={{ color: "#CCC" }}>No image to preview</p>}
         </Form>
      ...
   ...
...

4. Add the onChange handler for the function to the image input. The full file should now have the code below:

import React, { useState, useCallback } from 'react' 
import { Form, FormControl, Button, } from 'react-bootstrap' 
import classes from './ImageUploadForm.module.css' 

const ImageUploadForm = (props) => { 
    let [galleryName, setGalleryName] = useState('friend') // set starting value to 'friend'
    let [name, setName] = useState('')
    let [file, setFile] = useState(null)
    let [fileSrc, setFileSrc] = useState('')

    const fileStaging = useCallback((e) => {
        if (props.type === 'file') {
            setFile(e.target.files[0])

            let reader = new FileReader();

            try {
                reader.readAsDataURL(e.target.files[0])
            } catch (e) {
                setFileSrc('')
            }

            reader.addEventListener("load", function() {
                setFileSrc(reader.result)
            }, false)
        } else {
            setFileSrc(e.target.value)
        }
    }, [props.type])

    return (
        <Form className="my-4">
            <Form.Row className="text-left">
                <Form.Group>
                    <Form.Label>Gallery</Form.Label>
                    <Form.Text className="text-muted">
                        Select upload gallery.
                    </Form.Text>
                    <Form.Check 
                        type="radio"
                        label="Friend"
                        checked={galleryName === "friend"}
                        onChange={() => setGalleryName("friend")}
                        />
                    <Form.Check 
                        type="radio"
                        label="Foe"
                        checked={galleryName === "foe"}
                        onChange={() => setGalleryName("foe")}
                        />
                </Form.Group>
            </Form.Row>
            {props.endpoint === 'enroll' ?
            <Form.Row className="text-left">
                <Form.Group>
                    <Form.Label>Name</Form.Label>
                    <FormControl
                        type="text"
                        placeholder="Subject name"
                        onChange={(e) => setName(e.target.value)}
                        value={name}
                        required
                    />
                </Form.Group>
            </Form.Row>
            : null
            }
            <Form.Row>
                <div className="input-group d-flex justify-content-center mb-3">
                    <div className="input-group-prepend">
                        <Button type="submit" variant="primary">Upload</Button>
                    </div>
                    <div className={props.type === 'file' ? "custom-file" : ''}>
                        <label className={props.type === 'file' ? "custom-file-label text-left" : 'text-center'}>{!file ? props.label : file.name}</label>
                        <input 
                            required
                            type={props.type}
                            className={props.type === 'file' ? "custom-file-input" : "form-control"}
                            placeholder={props.placeholder}
                            onChange={(e) => fileStaging(e)}
                            />
                    </div>
                </div>
            </Form.Row>
            <h2>Image Preview</h2>
            {fileSrc ? <figure><img className={classes.Image} alt="" src={fileSrc} /></figure> : <p style={{ color: "#CCC" }}>No image to preview</p>}
        </Form>
    )
}

export default ImageUploadForm

Images can now be previewed!

This is image title

5. If we add a big image it will overflow the column and take over the page. Add the following CSS to ImageUploadForm.module.css.

.Image {
    max-width: 50%
}

One of the final things that needs to be implemented is a submit function that sends the data we have added to our backend. Currently, we do not have a route set up on the backend to receive the data. Yet we can still get the submit function set up in the way that we want the backend to receive the data.

Add Submit Function

1.We will use the popular library axios to send our data to the backend. In the terminal, while in face_recognition/client install axios:

npm install axios --save

Remember, this component will be used for two kinds of data submission. We will need to create a data payload object to send as a POST request and the contents of that data object will depend on which type of form is being used to submit the data.

Thankfully, a prop is being passed in the form that distinguishes between the two types: endpoint.

The function conditionally adds the subject_id value if the endpoint prop has a value of ‘enroll’.

2. Add the handleSubmit function to ImageUploadForm.js underneath the fileStaging function.

...
   const handleSubmit = (e) => {
        e.preventDefault() // will stop the page from refreshing on submit

        // set alert variable to null

        // constructs data payload
        let data = {
            gallery_name: galleryName,
            image: fileSrc
        }

        // adds subject_id if we are enrolling a new person
        if (props.endpoint === 'enroll') {
            data = {
                ...data, // spread operater - add all the properties in the previously declared data object to this object
                subject_id: name
            }
        }

        console.log(data) // log the data to make sure that it is beng sent the way we want
        axios.post(`/api/upload/${props.endpoint}`, data)
        .then(response => {
            // set alert variable
        })
        .catch(e => {
            set alert variable
        })
    }
...

3. Add the onSubmit handler to the `` tag.

<Form onSubmit={handleSubmit} className="my-4">

Now, submit the form with data. It will fail, but it your data payload will be logged to the console.

Build Route for Uploads

In the submit function we specified a URL to send the data to (/api/upload/${props.endpoint}). We used a string literal that uses back ticks—not quotes—to dynamically change the last part of the URL. There are only two values that we are giving the ‘endpoint’ prop: ‘enroll’ and ‘recognize’.

However, we need to build those routes on the backend.

1.In the terminal navigate to face_recognition/server and run the command npm run dev. We set-up this command earlier in the example.

Listening on port 3001 should be logged to the console. The nodemon server is now listening for changes in our files. This will help us develop and catch mistakes faster.

2. In server, make a directory src and inside of that folder make another directory routes.

3. In routes, make the file upload.js and add the two routes that we talked about earlier.

// upload.js

const router = require('express').Router();

router.route('/enroll').post( async (req, res) => {
    // enroll route
})

router.route('/recognize').post( async (req, res) => {
    // recognize route
})

module.exports = router;

4. The express application does not know about this file. In server.js import the router and set up the route middleware.

// server.js
const express = require('express');
const path = require('path');
require('dotenv').config()

// Import route
const uploadRouter = require('./src/routes/upload') // NEW

// Create App
const app = express();
const port = process.env.PORT || 3001;

// Adds a parsed json body object to req
app.use(express.json({ limit: '10000kb' }));

// Set route middleware
app.use('/api/upload', uploadRouter)               // NEW

// Needed for express to find static assets
//app.use(express.static(path.resolve('client', 'build')));

// Needed so express can return an actual webpage
//app.get('*', (req, res) => {
//    res.sendFile(path.resolve('client', 'build', 'index.html'));
//});

// console.log that your server is up and running
app.listen(port, () => console.log(`Listening on port ${port}`));

Add RapidAPI Credentials and API Calls to the Route

Back in the RapidAPI marketplace, pull up the Kairos Face Recognition dashboard. Locate the two endpoints that we will use (enroll and recognize).

Notice the headers are the same in both endpoints. Furthermore, the HTTP request URL is mostly the same with the exception of the last word.

1.Pull the header information into the route and create a header object. Add another variable named baseUrl and assign it the URL section that doesn’t change between the two routes.

const router = require('express').Router();

const headers = {
    "content-type":"application/json",
    "x-rapidapi-host":"kairosapi-karios-v1.p.rapidapi.com",
    "x-rapidapi-key": process.env.KAIROS_API_KEY,
    "accept":"application/json"
}

const baseUrl = "https://kairosapi-karios-v1.p.rapidapi.com/"

router.route('/enroll').post( async (req, res) => {
...

Take note that I didn’t paste in my api-key. We are going to use the dotenv library that we installed earlier to add this

2. Create a file in the server folder named .env. Add your api-key to that file.

// .env

KAIROS_API_KEY=apikey

If we were pushing this up to a Git repository, we would add ‘.env’ to the .gitignore file so our API key isn’t public or shared among other collaborators.

3. Require the dotenv file in server.js, so our variables are loaded into the app. Underneath the imports add the line:

require('dotenv').config()

Now that we have the header object and base URL, it’s easy to build axios calls.

4. Install axios on the backend and import it into upload.js.

On the frontend, we formed the data to have key values that match what the Kairos API expects as parameter values (subject_id, gallery_name, image). This will make it easy for us to take the request body and simply place it into the request to the Kairos API.

5. Add the Kairos API calls to each route.

const router = require('express').Router();
const axios = require('axios')

router.route('/enroll').post( async (req, res) => {
    let data = {
        ...req.body
    }

    const url = baseUrl + "enroll"

    try {
        const response = await axios({ 
            "method": "POST",
            url,
            headers,
            data
        })
    } catch(e) {
        console.log(e);
        res.status(500).send();
    }
})

router.route('/recognize').post( async (req, res) => {
    let data = {
        ...req.body
    }

    const url = baseUrl + "recognize"

    try {
        const response = await axios({ 
            "method": "POST",
            url,
            headers,
            data
        })

    } catch(e) {
        console.log(e);
        res.status(500).send();
    }
})

module.exports = router;

We get the data from the front end and submit it to the Kairos API, but we don’t send any useful information back. We must inspect the response objects that we get from Kairos.

Building Useful Responses

We can test the endpoints in the RapidAPI dashboard and examine the response objects.

When we enroll a subject, and it’s successful, the response looks like:

{
   "face_id": "68267b4f16394218826",
   "images": [
     {
         "attributes": {
         // demographic information
      },
         "transaction": {
            "confidence": 0.99648, // I left this here because it's the confidence level ID that was discussed at beginning of article
         }
     }
   ],
}

If the image is low resolution, or if it does not contain a face, the response fails. The API does not return an error status, it returns an error object.

{
   "Errors":[
      {
          "ErrCode":5001
          "Message":"invalid url was sent"
      }
   ]
}

We need to check the response for the ‘Errors’ parameter, and if it exists we need to send that error back to the front end. If it succeeds, we can send back whatever information we would like to.

For the enroll endpoint, we will simply send back a nice success message.

However, the recognize response has other information we want to use. If the Kairos API recognizes a face in an image it will return a ‘candidates’ object with the subject_id of the person it recognizes.

Furthermore, if it does not recognize the face, it will not have a candidates object. Knowing this, we can build string responses that send back data in an easy to display format.

1. Insert the remaining code into upload.js. The file should have the contents below:

const router = require('express').Router();
const axios = require("axios");

const headers = {
    "content-type":"application/json",
    "x-rapidapi-host":"kairosapi-karios-v1.p.rapidapi.com",
    "x-rapidapi-key": process.env.KAIROS_API_KEY,
    "accept":"application/json"
}

const baseUrl = "https://kairosapi-karios-v1.p.rapidapi.com/"

router.route('/enroll').post( async (req, res) => {
    let data = {
        ...req.body
    }

    const url = baseUrl + "enroll"

    try {
        const response = await axios({ 
            "method": "POST",
            url,
            headers,
            data
        })

        const params = Object.keys(response.data)

        // check for errors
        if (params.includes('Errors')) {
            console.log(response.data)
            return res.status(400).send({variant:"danger", text: response.data.Errors[0].Message})
        }

        // return a simple string if the add was successful
        res.send({variant:'success', text: `Success! ${data.subject_id} added.`})
    } catch(e) {
        console.log(e);
        res.status(500).send({variant: 'danger', text: 'Server error.'});
    }
})

router.route('/recognize').post( async (req, res) => {
    let data = {
        ...req.body
    }

    const url = baseUrl + "recognize"

    try {
        const response = await axios({ 
            "method": "POST",
            url,
            headers,
            data
        })

        const params = Object.keys(response.data)

        if (params.includes('Errors')) {
            return res.status(400).send({variant: "danger", text: response.data.Errors[0].Message})
        }

        let subjects = []

        // check the response for candidates
        response.data.images.map(item => {
            console.log(item)
            if (item.candidates) {
                subjects.push(item.candidates[0].subject_id)
            }
        })

        // build string responses that contain the subjects that were found, or not found in the image
        if (subjects.length < 1) {
            return res.send({variant: "info", text: "No faces were recognized. Exercise caution."})
        }

        if (data.gallery_name === 'foe') {
            const foeString = `Be careful we recognize ${subjects.join(' ')} as foe!`

            res.send({variant: 'danger', text: foeString})
        } else {
            const friendString = `Hoozah! We recognize friends! That's ${subjects.join(' and ')}`

            res.send({variant: 'success', text: friendString})
        }
    } catch(e) {
        console.log(e);
        res.status(500).send({variant: 'danger', text: 'Server error.'});
    }
})

module.exports = router;

Create the Message Component In The Frontend

There is not a way for us to display useful messages or data on the front end. Yet, you may have noticed how we are structuring the response objects in upload.js:

{
   variant: 'danger', 
   text: 'Server error.'
}

The Message component will take in a string ‘variant’ that corresponds to allowed property values for the Alert components variant prop. The Alert component is part of the bootstrap library and can have values of ‘success’, ‘danger’, ‘primary’, ‘info’, ‘light’, ‘dark’, and a few others.

1.In components create the Message directory. Inside of that folder add the file Message.js.

2. Add the below code to Message.js

import React from 'react'
import { Alert } from 'react-bootstrap'

const message = (props) => {
    const message = props.message

    return (
        <div>
            {message && <Alert variant={props.message.variant}>{props.message.text}</Alert>}
        </div>
    )
}

export default message

It is almost time to add our subjects and test our app!

Finishing Up the ImageUploadForm

The final touches to the form component are:

  • import the Message component
  • declare a variable for the message component
  • set the variable value in the handleSubmit function, and;
  • display the message component when it has a value

The below code is what the final ImageUploadForm.js should contain.

I’ll add comments next to the lines that were added.

import React, { useState, useCallback } from 'react' 
import { Form, Button, FormControl} from 'react-bootstrap' 
import classes from './ImageUploadForm.module.css' 
import axios from 'axios' 
import Message from '../Message/Message' // NEW 

const ImageUploadForm = (props) => { 
    let [alert, setAlert] = useState(null) // NEW 
    let [file, setFile] = useState(null) 
    let [fileSrc, setFileSrc] = useState('') 
    let [galleryName, setGalleryName] = useState('friend')
    let [name, setName] = useState('')

    const fileStaging = useCallback((e) => {
        if (props.type === 'file') {
            setFile(e.target.files[0])

            let reader = new FileReader();

            try {
                reader.readAsDataURL(e.target.files[0])
            } catch (e) {
                setAlert({variant:'danger', text:'Please select valid image.'})  // NEW
                setFileSrc('')
            }

            reader.addEventListener("load", function() {
                setFileSrc(reader.result)
            }, false)
        } else {
            setFileSrc(e.target.value)
        }
    }, [props.type])

    const handleSubmit = (e) => {
        e.preventDefault()

        setAlert(null)             // NEW

        let data = {
            gallery_name: galleryName,
            image: fileSrc
        }

        if (props.endpoint === 'enroll') {
            data = {
                ...data,
                subject_id: name
            }
        }

        axios.post(`/api/upload/${props.endpoint}`, data)
        .then(response => {
            setAlert(response.data)     // NEW
        })
        .catch(e => {
            setAlert(e.response.data)   // NEW
        })
    }

    return (
        <Form onSubmit={handleSubmit} className="my-4">
            {alert && <Message message={alert} />}          // NEW
            <Form.Row className="text-left">
                <Form.Group>
                    <Form.Label>Gallery</Form.Label>
                    <Form.Text className="text-muted">
                        Select upload gallery.
                    </Form.Text>
                    <Form.Check 
                        type="radio"
                        label="Friend"
                        checked={galleryName === "friend"}
                        onChange={() => setGalleryName("friend")}
                        />
                    <Form.Check 
                        type="radio"
                        label="Foe"
                        checked={galleryName === "foe"}
                        onChange={() => setGalleryName("foe")}
                        />
                </Form.Group>
            </Form.Row>
            {props.endpoint === 'enroll' ?
            <Form.Row className="text-left">
                <Form.Group>
                    <Form.Label>Name</Form.Label>
                    <FormControl
                        type="text"
                        placeholder="Subject name"
                        onChange={(e) => setName(e.target.value)}
                        value={name}
                        required
                    />
                </Form.Group>
            </Form.Row>
            : null
            }
            <Form.Row>
                <div className="input-group d-flex justify-content-center mb-3">
                    <div className="input-group-prepend">
                        <Button type="submit" variant="primary">Upload</Button>
                    </div>
                    <div className={props.type === 'file' ? "custom-file" : ''}>
                        <label className={props.type === 'file' ? "custom-file-label text-left" : 'text-center'}>{!file ? props.label : file.name}</label>
                        <input 
                            required
                            type={props.type}
                            className={props.type === 'file' ? "custom-file-input" : "form-control"}
                            placeholder={props.placeholder}
                            onChange={(e) => fileStaging(e)}
                            />
                    </div>
                </div>
            </Form.Row>
            <h2>Image Preview</h2>
            {fileSrc ? <figure><img className={classes.Image} alt="" src={fileSrc} /></figure> : <p style={{ color: "#CCC" }}>No image to preview</p>}
        </Form>
    )
}

export default ImageUploadForm

Test

Time to use our app! To recap, we will be creating two galleries with Kairos. Kairos saves the gallery’s name once it is used and creates a new gallery if the name has not been used. What is great about that is we don’t need a database to store the subject_ids, face dimensions, or images: Kairos does that for us.

I am going to be pulling image addresses off of Google to test the app and will doing a LOTR themed testing.

First, let’s add Gollum to the ‘foe’ gallery:

This is image title

Second, upload two friends, Aragorn and Gandalf:

Third, check the gallery ‘foe’ with a different image the contains Gollum:

This is image title

Fourth, see if our app can recognize Gandalf and Aragorn in a different image:

This is image title

Conclusion

I had a lot of fun working with this API and I hope that the example app showed you how to build something even better.

Remember, there are still many ethical concerns surrounding facial recognition and they should be considered before building something that could compromise someone’s safety.

That being said, I hope you found this article helpful and leave a comment or question if you like!

Thank you for reading!

#REST API Tutorials #javascript #express.js #kairos #developer

What is GEEK

Buddha Community

Building a Simple App with Kairos Facial Recognition API in Javascript
Fredy  Larson

Fredy Larson

1595059664

How long does it take to develop/build an app?

With more of us using smartphones, the popularity of mobile applications has exploded. In the digital era, the number of people looking for products and services online is growing rapidly. Smartphone owners look for mobile applications that give them quick access to companies’ products and services. As a result, mobile apps provide customers with a lot of benefits in just one device.

Likewise, companies use mobile apps to increase customer loyalty and improve their services. Mobile Developers are in high demand as companies use apps not only to create brand awareness but also to gather information. For that reason, mobile apps are used as tools to collect valuable data from customers to help companies improve their offer.

There are many types of mobile applications, each with its own advantages. For example, native apps perform better, while web apps don’t need to be customized for the platform or operating system (OS). Likewise, hybrid apps provide users with comfortable user experience. However, you may be wondering how long it takes to develop an app.

To give you an idea of how long the app development process takes, here’s a short guide.

App Idea & Research

app-idea-research

_Average time spent: two to five weeks _

This is the initial stage and a crucial step in setting the project in the right direction. In this stage, you brainstorm ideas and select the best one. Apart from that, you’ll need to do some research to see if your idea is viable. Remember that coming up with an idea is easy; the hard part is to make it a reality.

All your ideas may seem viable, but you still have to run some tests to keep it as real as possible. For that reason, when Web Developers are building a web app, they analyze the available ideas to see which one is the best match for the targeted audience.

Targeting the right audience is crucial when you are developing an app. It saves time when shaping the app in the right direction as you have a clear set of objectives. Likewise, analyzing how the app affects the market is essential. During the research process, App Developers must gather information about potential competitors and threats. This helps the app owners develop strategies to tackle difficulties that come up after the launch.

The research process can take several weeks, but it determines how successful your app can be. For that reason, you must take your time to know all the weaknesses and strengths of the competitors, possible app strategies, and targeted audience.

The outcomes of this stage are app prototypes and the minimum feasible product.

#android app #frontend #ios app #minimum viable product (mvp) #mobile app development #web development #android app development #app development #app development for ios and android #app development process #ios and android app development #ios app development #stages in app development

Carmen  Grimes

Carmen Grimes

1595494844

How to start an electric scooter facility/fleet in a university campus/IT park

Are you leading an organization that has a large campus, e.g., a large university? You are probably thinking of introducing an electric scooter/bicycle fleet on the campus, and why wouldn’t you?

Introducing micro-mobility in your campus with the help of such a fleet would help the people on the campus significantly. People would save money since they don’t need to use a car for a short distance. Your campus will see a drastic reduction in congestion, moreover, its carbon footprint will reduce.

Micro-mobility is relatively new though and you would need help. You would need to select an appropriate fleet of vehicles. The people on your campus would need to find electric scooters or electric bikes for commuting, and you need to provide a solution for this.

To be more specific, you need a short-term electric bike rental app. With such an app, you will be able to easily offer micro-mobility to the people on the campus. We at Devathon have built Autorent exactly for this.

What does Autorent do and how can it help you? How does it enable you to introduce micro-mobility on your campus? We explain these in this article, however, we will touch upon a few basics first.

Micro-mobility: What it is

micro-mobility

You are probably thinking about micro-mobility relatively recently, aren’t you? A few relevant insights about it could help you to better appreciate its importance.

Micro-mobility is a new trend in transportation, and it uses vehicles that are considerably smaller than cars. Electric scooters (e-scooters) and electric bikes (e-bikes) are the most popular forms of micro-mobility, however, there are also e-unicycles and e-skateboards.

You might have already seen e-scooters, which are kick scooters that come with a motor. Thanks to its motor, an e-scooter can achieve a speed of up to 20 km/h. On the other hand, e-bikes are popular in China and Japan, and they come with a motor, and you can reach a speed of 40 km/h.

You obviously can’t use these vehicles for very long commutes, however, what if you need to travel a short distance? Even if you have a reasonable public transport facility in the city, it might not cover the route you need to take. Take the example of a large university campus. Such a campus is often at a considerable distance from the central business district of the city where it’s located. While public transport facilities may serve the central business district, they wouldn’t serve this large campus. Currently, many people drive their cars even for short distances.

As you know, that brings its own set of challenges. Vehicular traffic adds significantly to pollution, moreover, finding a parking spot can be hard in crowded urban districts.

Well, you can reduce your carbon footprint if you use an electric car. However, electric cars are still new, and many countries are still building the necessary infrastructure for them. Your large campus might not have the necessary infrastructure for them either. Presently, electric cars don’t represent a viable option in most geographies.

As a result, you need to buy and maintain a car even if your commute is short. In addition to dealing with parking problems, you need to spend significantly on your car.

All of these factors have combined to make people sit up and think seriously about cars. Many people are now seriously considering whether a car is really the best option even if they have to commute only a short distance.

This is where micro-mobility enters the picture. When you commute a short distance regularly, e-scooters or e-bikes are viable options. You limit your carbon footprints and you cut costs!

Businesses have seen this shift in thinking, and e-scooter companies like Lime and Bird have entered this field in a big way. They let you rent e-scooters by the minute. On the other hand, start-ups like Jump and Lyft have entered the e-bike market.

Think of your campus now! The people there might need to travel short distances within the campus, and e-scooters can really help them.

How micro-mobility can benefit you

benefits-micromobility

What advantages can you get from micro-mobility? Let’s take a deeper look into this question.

Micro-mobility can offer several advantages to the people on your campus, e.g.:

  • Affordability: Shared e-scooters are cheaper than other mass transportation options. Remember that the people on your campus will use them on a shared basis, and they will pay for their short commutes only. Well, depending on your operating model, you might even let them use shared e-scooters or e-bikes for free!
  • Convenience: Users don’t need to worry about finding parking spots for shared e-scooters since these are small. They can easily travel from point A to point B on your campus with the help of these e-scooters.
  • Environmentally sustainable: Shared e-scooters reduce the carbon footprint, moreover, they decongest the roads. Statistics from the pilot programs in cities like Portland and Denver showimpressive gains around this key aspect.
  • Safety: This one’s obvious, isn’t it? When people on your campus use small e-scooters or e-bikes instead of cars, the problem of overspeeding will disappear. you will see fewer accidents.

#android app #autorent #ios app #mobile app development #app like bird #app like bounce #app like lime #autorent #bird scooter business model #bird scooter rental #bird scooter rental cost #bird scooter rental price #clone app like bird #clone app like bounce #clone app like lime #electric rental scooters #electric scooter company #electric scooter rental business #how do you start a moped #how to start a moped #how to start a scooter rental business #how to start an electric company #how to start electric scooterrental business #lime scooter business model #scooter franchise #scooter rental business #scooter rental business for sale #scooter rental business insurance #scooters franchise cost #white label app like bird #white label app like bounce #white label app like lime

Carmen  Grimes

Carmen Grimes

1595491178

Best Electric Bikes and Scooters for Rental Business or Campus Facility

The electric scooter revolution has caught on super-fast taking many cities across the globe by storm. eScooters, a renovated version of old-school scooters now turned into electric vehicles are an environmentally friendly solution to current on-demand commute problems. They work on engines, like cars, enabling short traveling distances without hassle. The result is that these groundbreaking electric machines can now provide faster transport for less — cheaper than Uber and faster than Metro.

Since they are durable, fast, easy to operate and maintain, and are more convenient to park compared to four-wheelers, the eScooters trend has and continues to spike interest as a promising growth area. Several companies and universities are increasingly setting up shop to provide eScooter services realizing a would-be profitable business model and a ready customer base that is university students or residents in need of faster and cheap travel going about their business in school, town, and other surrounding areas.

Electric Scooters Trends and Statistics

In many countries including the U.S., Canada, Mexico, U.K., Germany, France, China, Japan, India, Brazil and Mexico and more, a growing number of eScooter users both locals and tourists can now be seen effortlessly passing lines of drivers stuck in the endless and unmoving traffic.

A recent report by McKinsey revealed that the E-Scooter industry will be worth― $200 billion to $300 billion in the United States, $100 billion to $150 billion in Europe, and $30 billion to $50 billion in China in 2030. The e-Scooter revenue model will also spike and is projected to rise by more than 20% amounting to approximately $5 billion.

And, with a necessity to move people away from high carbon prints, traffic and congestion issues brought about by car-centric transport systems in cities, more and more city planners are developing more bike/scooter lanes and adopting zero-emission plans. This is the force behind the booming electric scooter market and the numbers will only go higher and higher.

Companies that have taken advantage of the growing eScooter trend develop an appthat allows them to provide efficient eScooter services. Such an app enables them to be able to locate bike pick-up and drop points through fully integrated google maps.

List of Best Electric Bikes for Rental Business or Campus Facility 2020:

It’s clear that e scooters will increasingly become more common and the e-scooter business model will continue to grab the attention of manufacturers, investors, entrepreneurs. All this should go ahead with a quest to know what are some of the best electric bikes in the market especially for anyone who would want to get started in the electric bikes/scooters rental business.

We have done a comprehensive list of the best electric bikes! Each bike has been reviewed in depth and includes a full list of specs and a photo.

Billy eBike

mobile-best-electric-bikes-scooters https://www.kickstarter.com/projects/enkicycles/billy-were-redefining-joyrides

To start us off is the Billy eBike, a powerful go-anywhere urban electric bike that’s specially designed to offer an exciting ride like no other whether you want to ride to the grocery store, cafe, work or school. The Billy eBike comes in 4 color options – Billy Blue, Polished aluminium, Artic white, and Stealth black.

Price: $2490

Available countries

Available in the USA, Europe, Asia, South Africa and Australia.This item ships from the USA. Buyers are therefore responsible for any taxes and/or customs duties incurred once it arrives in your country.

Features

  • Control – Ride with confidence with our ultra-wide BMX bars and a hyper-responsive twist throttle.
  • Stealth- Ride like a ninja with our Gates carbon drive that’s as smooth as butter and maintenance-free.
  • Drive – Ride further with our high torque fat bike motor, giving a better climbing performance.
  • Accelerate – Ride quicker with our 20-inch lightweight cutout rims for improved acceleration.
  • Customize – Ride your own way with 5 levels of power control. Each level determines power and speed.
  • Flickable – Ride harder with our BMX /MotoX inspired geometry and lightweight aluminum package

Specifications

  • Maximum speed: 20 mph (32 km/h)
  • Range per charge: 41 miles (66 km)
  • Maximum Power: 500W
  • Motor type: Fat Bike Motor: Bafang RM G060.500.DC
  • Load capacity: 300lbs (136kg)
  • Battery type: 13.6Ah Samsung lithium-ion,
  • Battery capacity: On/off-bike charging available
  • Weight: w/o batt. 48.5lbs (22kg), w/ batt. 54lbs (24.5kg)
  • Front Suspension: Fully adjustable air shock, preload/compression damping /lockout
  • Rear Suspension: spring, preload adjustment
  • Built-in GPS

Why Should You Buy This?

  • Riding fun and excitement
  • Better climbing ability and faster acceleration.
  • Ride with confidence
  • Billy folds for convenient storage and transportation.
  • Shorty levers connect to disc brakes ensuring you stop on a dime
  • belt drives are maintenance-free and clean (no oil or lubrication needed)

**Who Should Ride Billy? **

Both new and experienced riders

**Where to Buy? **Local distributors or ships from the USA.

Genze 200 series e-Bike

genze-best-electric-bikes-scooters https://www.genze.com/fleet/

Featuring a sleek and lightweight aluminum frame design, the 200-Series ebike takes your riding experience to greater heights. Available in both black and white this ebike comes with a connected app, which allows you to plan activities, map distances and routes while also allowing connections with fellow riders.

Price: $2099.00

Available countries

The Genze 200 series e-Bike is available at GenZe retail locations across the U.S or online via GenZe.com website. Customers from outside the US can ship the product while incurring the relevant charges.

Features

  • 2 Frame Options
  • 2 Sizes
  • Integrated/Removable Battery
  • Throttle and Pedal Assist Ride Modes
  • Integrated LCD Display
  • Connected App
  • 24 month warranty
  • GPS navigation
  • Bluetooth connectivity

Specifications

  • Maximum speed: 20 mph with throttle
  • Range per charge: 15-18 miles w/ throttle and 30-50 miles w/ pedal assist
  • Charging time: 3.5 hours
  • Motor type: Brushless Rear Hub Motor
  • Gears: Microshift Thumb Shifter
  • Battery type: Removable Samsung 36V, 9.6AH Li-Ion battery pack
  • Battery capacity: 36V and 350 Wh
  • Weight: 46 pounds
  • Derailleur: 8-speed Shimano
  • Brakes: Dual classic
  • Wheels: 26 x 20 inches
  • Frame: 16, and 18 inches
  • Operating Mode: Analog mode 5 levels of Pedal Assist Thrott­le Mode

Norco from eBikestore

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The Norco VLT S2 is a front suspension e-Bike with solid components alongside the reliable Bosch Performance Line Power systems that offer precise pedal assistance during any riding situation.

Price: $2,699.00

Available countries

This item is available via the various Norco bikes international distributors.

Features

  • VLT aluminum frame- for stiffness and wheel security.
  • Bosch e-bike system – for their reliability and performance.
  • E-bike components – for added durability.
  • Hydraulic disc brakes – offer riders more stopping power for safety and control at higher speeds.
  • Practical design features – to add convenience and versatility.

Specifications

  • Maximum speed: KMC X9 9spd
  • Motor type: Bosch Active Line
  • Gears: Shimano Altus RD-M2000, SGS, 9 Speed
  • Battery type: Power Pack 400
  • Battery capacity: 396Wh
  • Suspension: SR Suntour suspension fork
  • Frame: Norco VLT, Aluminum, 12x142mm TA Dropouts

Bodo EV

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Manufactured by Bodo Vehicle Group Limited, the Bodo EV is specially designed for strong power and extraordinary long service to facilitate super amazing rides. The Bodo Vehicle Company is a striking top in electric vehicles brand field in China and across the globe. Their Bodo EV will no doubt provide your riders with high-level riding satisfaction owing to its high-quality design, strength, breaking stability and speed.

Price: $799

Available countries

This item ships from China with buyers bearing the shipping costs and other variables prior to delivery.

Features

  • Reliable
  • Environment friendly
  • Comfortable riding
  • Fashionable
  • Economical
  • Durable – long service life
  • Braking stability
  • LED lighting technology

Specifications

  • Maximum speed: 45km/h
  • Range per charge: 50km per person
  • Charging time: 8 hours
  • Maximum Power: 3000W
  • Motor type: Brushless DC Motor
  • Load capacity: 100kg
  • Battery type: Lead-acid battery
  • Battery capacity: 60V 20AH
  • Weight: w/o battery 47kg

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Building a Simple App with Kairos Facial Recognition API in Javascript

What is Facial Recognition?

Facial recognition is a system of processes or algorithms that translates the characteristics of a face from a digital source into numbers that can be used to later identify the face.

Face detection, and the ethics surrounding the practice, has become an important topic in tech and a valid topic in political discussions. Facial recognition has a few different names (i.e image processing, computer vision) and falls into the larger category of artificial intelligence and machine learning. It has grown hand-in-hand with the rise of data science practices, the popular programming language Python, and the aggregation of massive data stores. One of the data science techniques that can be used to identify a face is a neural network.

Neural networks are a bit beyond the scope of this article, but we should have the general idea before using the API. If we were to submit an image to a neural network it would be processed at different levels. The network would be trying to answer a question, for example, “Is there a face in this image?“. Sections of the photograph would be selected and the system would gather information on whether the lighting and colors reveal edges, curves—or an object. This information means nothing unless the system has something to compare it with.

The system, hypothetically, has patterns of data points that have been positively identified as resembling faces. If the data points collected from sections of the submitted photograph are consistent with the data point patterns of faces, then the neural network can answer, “Yes, there is a face in this photograph!”, or, “I don’t think there is anything here”. This is typically done with ‘confidence intervals’ that are between 0 and 1. We will be able to glimpse some of these data points in the response object from the Kairos Facial Recognition API.

Kairos API

In using the Kairos API, we remove the need to build our own face database and understand complicated statistical algorithms. This can save a company a lot of time and money. In addition, Kairos is simple. I was able to grasp the use cases for the nine endpoints listed in the dashboard with ease.

With Kairos, images that contain faces (that you hope to identify later) are put into galleries. For example, if I had three pictures of three different friends, I would add each of them to the gallery ‘Friends’. Later, I could use different endpoints (‘/recognize’, ‘/verify’) to identify my friends in group pictures or different individual pictures. I could check all my galleries, or submit an image and have the API search a specific gallery.

Kairos only accepts a few parameters across it’s endpoints:

  • “image”
  • “gallery_name”
  • “subject_id”
  • “selector”

This means that we can quickly build uncomplicated HTTP requests.

Furthermore, the “image” parameter accepts a publicly accessible URL, file upload or base64 encoded photo.

I hope to show you how simple it is to create galleries, upload pictures, and recognize images in the example javascript app below. We will build a ReactJS frontend that allows users to upload images to either the ‘friend’ gallery, or the ‘foe’ gallery. Next, the frontend will send the image data to our node.js backend that will fire off the request to the Kairos API for processing and return the data to the user in the frontend. We will enroll subjects in both galleries, then identify our friends and foes in later images.

Connect to the Kairos Face Recognition API

How to Build a Facial Recognition App with JavaScript

Prerequisites

In order the complete the application there are a few items that need to be completed.

First, you will need a RapidAPI account. Second, after setting up an account you will need to subscribe to the Kairos API. You can’t beat the basic subscription. We get 1000 API calls a month, and after that, it’s $0.0001 each request. That will be plenty for us in this example. Next, make sure that you have:

  • Node >= 8.10 and npm >= 5.6 on your machine
  • some familiarity with how to open and use a command-line tool
  • an internet connection
  • a code editor (I recommend VS Code)
  • some familiarity with Javascript, specifically React and Node.
  • I will be using the bash terminal on macOS but most of the commands should be the same with the Windows command prompt.

We will also need React >=16.8.0, however, if you are following the instructions, we will be downloading an acceptable version in the process.

Steps

Setting Up the Project

1.Open up a new terminal

2. Navigate to a good directory using cd.

3. Make a new directory named face_recognition:

mkdir face_recognition

4. Move into that directory:

cd face_recognition

5. Run npx create-react-app client. Npx is a program that ships with npm. We are creating a new React project using the popular project Create React App and placing it in a folder named ‘client’. After a few minutes, you should see the new folder appear in face_recognition.

6. In face_recognition, make a new directory server and cd into the empty folder.

7. Initialize a new npm module:

npm init -y

The -y flag fills out the information that we would be prompted to answer that describes the package. Filling out this information is unnecessary in this tutorial. We now have our front end folder and our server folder ready for installations and modifications!

Set Up Express Server

1.Open up your code editor. I am using VS Code with the command line interface installed, so if I am in the root of our project (face_recognition) I can execute code . and VS Code will open in that directory. Keep the terminal open because we will be installing packages soon.

2. In the terminal, navigate into server and install express and dotenv:

npm install express dotenv --save

We will use express as our web application and dotenv to store our RapidAPI key so we don’t accidentally commit it to a repository. We will not be pushing the code base to Github, but it’s a good habit to have.

2. Install nodemon for development:

npm install nodemon --save-dev

3. Add a dev script to server/package.json that will make it easier for us to use nodemon in development.

// server/package.json

{
  ...
  "scripts": {
    "start": "node server.js",
    "dev": "nodemon server.js -e js",  // our new script
    ...
}

4. Make a new file server.js in the folder server. Add the below code to it.

// server.js
const express = require('express');

//const path = require('path');

// Import routes

// Create App
const app = express();
const port = process.env.PORT || 3001;

// Adds a parsed json body object to req
app.use(express.json({ limit: '10000kb' }));

// Future route
// app.use('/api/', router);

// DEPLOYMENT: for express to find static assets in the React build
// app.use(express.static(path.resolve('client', 'build')));

// DEPLOYMENT: so express can return an actual webpage
// app.get('*', (req, res) => {
      res.sendFile(path.resolve('client', 'build', 'index.html'));
// });

// console.log that your server is up and running
app.listen(port, () => console.log(`Listening on port ${port}`));

The majority of the code is commented out because it’s not time for it to be used. The code blocks that are commented out and labeled “DEPLOYMENT” will not be used in this app, but would be used if you were to deploy to a server. They allow the express application to find the React frontend and serve static files.

In this file, so far, we are creating the express app, adding JSON parsing middleware, and telling the app to listen for requests on port 3001. Easy enough! Next, we’ll go to the front end for general set up, and make sure that it can communicate with our backend.

Set Up Frontend

In the client folder there is another package.json file. However, it has different contents and is not related to the package.json in the server folder because, although our client and server folders are in the same directory, they are separate entities.

What we are going to do is open up a path of communication between the two folders by adding a directive in package.json. The directive will proxy the requests that we make on the frontend to port 3001 (the port we specified in the express application).

1.Add proxy to front-end

// client/package.json

{
  ...
  },
  "proxy": "http://locahost:3001"
}

Now, when we send requests on the front end to the root url they will be received by our backend.

2. We are going to do some basic clean up in our client folder and install a few packages that we will use later. Open App.css and fill it with the code below:

.App {
  display:flex;
  flex-direction: column;
  min-height: 100vh;
}

.App-header {
  background-color: #282c34;
  min-height: 300px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  font-size: calc(10px + 2vmin);
  color: white;
}

main {
  flex-grow: 1;
  text-align: center;
  padding: 25px;
}

footer {
  padding: 2px;
  min-height: 100px;
  display: flex!important;
  flex-direction: column;
  justify-content: center;
  background: #EEEEEE;
  font-size: small;
  text-align: center;
}

header {
  padding: 25px;
}

Explaining the CSS is beyond the scope of the article. The code above will give us a nice layout to build our app.

3. Create React App ships with some example content that is displayed in App.js, but we are going to replace it with our own set up. Open App.js and add the code:

import React from 'react';
import './App.css';

function App() {
  return (
    <div className="App">
      <header className="App-header">
        <h1>Friend or Foe</h1>
      </header>
      <main>
        
      </main>
      <footer>
        Page created by yournamehere
      </footer>
    </div>
  );
}

export default App;

4. We are almost ready to fire up our app. Before we do that, let’s install a few packages that we are going to use extensively for styling. Double check that your terminal is in the client folder before executing the next command.

npm install react-bootstrap bootstrap

5. Import the bootstrap CSS into the page and add content to the `` tag of our app.

// App.js
...
import 'bootstrap/dist/css/bootstrap.min.css'
import { Container, Row, Col } from 'react-bootstrap'

function App() {
  return (
    <div className="App">
      ...
      <main>
        <Container>
          <Row className="justify-content-md-center">
            <Col md="6">
              <h1>Test person form</h1>
            </Col>
            <Col md="6">
              <h1>Add person form</h1>
            </Col>
          </Row>
        </Container>
      </main>
      ...
    </div>
  );
}

export default App;

We are now ready to start our application and see what we are working with!

5. In client run npm start. The development server will start up and our app will be viewable at http://localhost:3000.

Your page should look like this:

This is image title

Build Input Form

As can be seen from the headings, we are going to have a form where an image is tested for recognition and another form where we add images to galleries. This is going to be the same ReactJS component, but we are going to add conditionals that decide how the component is rendered. We are going to use React hooks to store our form data.

1.Make a directory in the src folder named components. Inside that folder create another folder ImageUploadForm. Inside ImageUploadForm create two files;

  1. ImageUploadForm.js
  2. ImageUploadForm.module.css

In ImageUploadForm.js we are going to start to build a form, using the react-bootstrap library, that has three inputs. These inputs correspond to three of the basic parameters I mentioned earlier (gallery_name, image, subject_id).

2. Add the code below that structures our form.

import React from 'react'
import { 
    Form 
    } from 'react-bootstrap'
import classes from './ImageUploadForm.module.css'

const ImageUploadForm = (props) => {
    return (
        <Form className="my-4">
            <Form.Row className="text-left">
                select gallery
            </Form.Row>
            <Form.Row className="text-left">
                enter subject name
            </Form.Row>
            <Form.Row>
                select or input image
            </Form.Row>
        </Form>
    )
}

export default ImageUploadForm

3. Import our new form into App.js and add it to our columns.

// App.js
...

import ImageUploadForm from './components/ImageUploadForm/ImageUploadForm'

...
// App.js
...
import ImageUploadForm from './components/ImageUploadForm/ImageUploadForm'

...
   ...
      <main> 
        <Container> 
          <Row className="justify-content-md-center"> 
            <Col md="6"> 
              <h1>Test person form</h1>
              <ImageUploadForm />
            </Col> 
            <Col md="6"> 
              <h1>Add person form</h1>
              <ImageUploadForm /> 
            </Col> 
          </Row>
        </Container>
      </main>
   ...
...

That shouldn’t change the look of the app, but it will when we start adding inputs.

The first input we are going to add are radio buttons that select the gallery name. Our app is going to have two galleries: “friend” and “foe”.

We will need to import the { useState } hook at the top of the page and declare our hook at the top of the components. If you are new to hooks, they are essentially a simple way to hold and change state in a component.

4. Replace “select gallery” with the code below.

// Image UploadForm.js 
import React, { useState } from 'react' 
... 

const ImageUploadForm = (props) => { 
   let [galleryName, setGalleryName]= useState('friend') // set starting value to 'friend'
      ...
         ...
            ...
                <Form.Group>
                    <Form.Label>Gallery</Form.Label>
                    <Form.Text className="text-muted">
                        Select upload gallery.
                    </Form.Text>
                    <Form.Check 
                        type="radio"
                        label="Friend"
                        checked={galleryName === "friend"}
                        onChange={() => setGalleryName("friend")}
                        />
                    <Form.Check 
                        type="radio"
                        label="Foe"
                        checked={galleryName === "foe"}
                        onChange={() => setGalleryName("foe")}
                        />
                </Form.Group>
            ...
         ...
      ...
   ...
}

Next, we are going to do something very similar to store the subject_id (name) variable, but we only want to show this input if we are adding someone to a gallery. Therefore, we will pass a ‘prop’ to each form that identifies which endpoint the form will be utilizing.

If we are testing a person we will set the endpoint prop to ‘recognize’, and if we are adding a person we will set the endpoint to ‘enroll’.

5. In App.js two variables above the App() function:

const recognize = "recognize"

const enroll = "enroll"

6. Add the prop ‘endpoint’ to each upload form. Give the ‘Add person’ form endpoint prop a value of {enroll} and the ‘Test person’ endpoint prop a value of {recognize}. It may seem weird to have variables that match their own string value, but we are going to use these values again and want to avoid hard coding those strings in four different places.

// App.js
...

const enroll = "enroll"
const recognize = "recognize"

...
   ...
      ...
         ...
            <Col md="6"> 
              <h1>Test person form</h1>
              <ImageUploadForm
                endpoint={recognize}
              />
            </Col> 
            <Col md="6"> 
              <h1>Add person form</h1>
              <ImageUploadForm
                endpoint={enroll}
              />
            </Col>
         ...
      ...
   ...
...

Back in ImageUploadForm.js we can check this prop and if it equals ‘enroll’ then we will display the ‘Name’ input.

7. Add the ‘Name’ input with a conditional to ImageUploadForm.js in replace of the row that has ‘enter subject name’. Remember to add the hook that declares the variable and set function.

...
   ...
      ...
         ...
            {props.endpoint === 'enroll' ?
            <Form.Row className="text-left">
                <Form.Group>
                    <Form.Label>Name</Form.Label>
                    <FormControl
                        type="text"
                        placeholder="Subject name"
                        onChange={(e) => setName(e.target.value)}
                        value={name}
                        required
                    />
                </Form.Group>
            </Form.Row>
            : null
            }
         ...
      ...
   ...
...

After adding the conditional input row your forms should look like this:

This is image title

The last input is the image input, but it will require a little more work.

Adding the Image Input

The image input comes in a few different forms. The Kairos API “image” parameter accepts a publicly accessible URL, file upload or base64 encoded photo. Our form is going to take an image upload, translate it to base64, and submit that string, or it will accept the URL string and submit that as the image parameter.

Therefore, we need two different inputs. In order to accomplish this, we are going to create two tabs in each column, one for URLs, and one for image uploads. We will then pass another prop specifying whether the form accepts ‘file’ or ‘text’.

1.Import the Tab component from react-bootstrap and duplicate the image forms. Each column should have two Tabs, two ImageUploadForms, and one form should have a prop type='file' while the other has a prop type='text'. We are going to add a placeholder prop for our text forms. App.js should have the following code:

import React from 'react'
import './App.css'
import 'bootstrap/dist/css/bootstrap.min.css'
import { Container, Row, Col, Tab, Tabs } from 'react-bootstrap'
import ImageUploadForm from './components/ImageUploadForm/ImageUploadForm'

const recognize = "recognize"
const enroll = "enroll"

function App() {
  return (
    <div className="App">
      <header className="App-header">
        <h1>Friend or Foe</h1>
      </header>
      <main>
        <Container fluid>
          <Row className="justify-content-md-around">
            <Col md="5">
              <h2>Test Person</h2>
              <Tabs defaultActiveKey="upload" id="uncontrolled-tab-example">
                <Tab eventKey="upload" title="Upload">
                  <ImageUploadForm
                    label="Select Image to Test"
                    type="file"
                    endpoint={recognize}
                  />
                </Tab>
                <Tab eventKey="url" title="URL">
                  <ImageUploadForm
                    label="Enter Image URL to Test"
                    type="text"
                    placeholder="Image address URL"
                    endpoint={recognize}
                  />
                </Tab>
              </Tabs>
            </Col>
            <Col md="5" className="bg-light">
              <h2>Add Person</h2>
              <Tabs defaultActiveKey="uploadAdd" id="uncontrolled-tab-example">
                <Tab eventKey="uploadAdd" title="Upload">
                  <ImageUploadForm
                    label="Select Image to Add"
                    type="file"
                    endpoint={enroll}
                  />
                </Tab>
                <Tab eventKey="urlAdd" title="URL">
                  <ImageUploadForm
                    label="Enter Image URL to Add"
                    type="text"
                    placeholder="Image address URL"
                    endpoint={enroll}
                  />
                </Tab>
              </Tabs>
            </Col>
          </Row>
        </Container>
      </main>
      <footer>
        Page created by yournamehere
      </footer>
    </div>
  );
}

export default App;

Now, you should be able to switch back and forth between the ‘Upload’ tab and the ‘URL’ tab. Nothing changes in the form yet because we have not added the image input.

2. In ImageUploadForm.js add the image input where it says ‘select or input image’. We will also need to import Button from react-bootstrap and create the file variable in state.

...
import {
   Form,
   Button,  //import button
   FormControl ) from 'react-bootstrap'                
   ...
	 
const ImageUploadForm = (props) => {
   ...
   let [file, setFile] = useState(null)  // add file to state
      ...
         ...
            ...
               <div className="input-group d-flex justify-content-center mb-3">
                    <div className="input-group-prepend">
                        <Button type="submit" variant="primary">Upload</Button>
                    </div>
                    <div className={props.type === 'file' ? "custom-file" : ''}>
                        <label className={props.type === 'file' ? "custom-file-label text-left" : 'text-center'}>{!file ? props.label : file.name}</label>
                        <input 
                            required
                            type={props.type}
                            className={props.type === 'file' ? "custom-file-input" : "form-control"}
                            placeholder={props.placeholder}
                            />
                    </div>
                </div>
            ...
         ...
      ...
   ...
}

You can now see that the input changes between a text image upload and a file image upload. This is because we are changing values in the code based on the props that the component is being passed.

Add Preview

It would be nice if our users could see the image that they are about to upload. Currently our image input isn’t added to state. We are going to build a file staging function that operates conditionally:

  1. If the image is uploaded, the file is converted to base64 and a local URL is created for the preview
  2. If the image input is a URL the string then we set the appropriate variables to the string

In addition, we will have an `` element that is waiting to receive a value for it’s src attribute.

1.In ImageUploadForm.js add another value to the state:

let [fileSrc, setFileSrc] = useState('')

2. Import the useCallback hook at the top of the page next to useState

import React, { useState, useCallback } from 'react'

The useCallback hook memoizes the function. This is beyond the scope of the article, and might be a little unnecessary for such a small app and function.

3. Add the fileStaging function to ImageUploadForm.js.

...
    const fileStaging = useCallback((e) => {
        if (props.type === 'file') {
            setFile(e.target.files[0])
    
            let reader = new FileReader();
    
            try {
                reader.readAsDataURL(e.target.files[0])
            } catch (e) {
                setFileSrc('')
            }
    
            reader.addEventListener("load", function() {
                setFileSrc(reader.result)
            }, false)
        } else {
            setFileSrc(e.target.value)
        }
    }, [props.type])
...

3. Add the image preview to the bottom of the form.

...
   ...
      ...
         ...
            <h2>Image Preview</h2>
            {fileSrc ? <figure><img className={classes.Image} alt="" src={fileSrc} /></figure> : <p style={{ color: "#CCC" }}>No image to preview</p>}
         </Form>
      ...
   ...
...

4. Add the onChange handler for the function to the image input. The full file should now have the code below:

import React, { useState, useCallback } from 'react' 
import { Form, FormControl, Button, } from 'react-bootstrap' 
import classes from './ImageUploadForm.module.css' 

const ImageUploadForm = (props) => { 
    let [galleryName, setGalleryName] = useState('friend') // set starting value to 'friend'
    let [name, setName] = useState('')
    let [file, setFile] = useState(null)
    let [fileSrc, setFileSrc] = useState('')

    const fileStaging = useCallback((e) => {
        if (props.type === 'file') {
            setFile(e.target.files[0])

            let reader = new FileReader();

            try {
                reader.readAsDataURL(e.target.files[0])
            } catch (e) {
                setFileSrc('')
            }

            reader.addEventListener("load", function() {
                setFileSrc(reader.result)
            }, false)
        } else {
            setFileSrc(e.target.value)
        }
    }, [props.type])

    return (
        <Form className="my-4">
            <Form.Row className="text-left">
                <Form.Group>
                    <Form.Label>Gallery</Form.Label>
                    <Form.Text className="text-muted">
                        Select upload gallery.
                    </Form.Text>
                    <Form.Check 
                        type="radio"
                        label="Friend"
                        checked={galleryName === "friend"}
                        onChange={() => setGalleryName("friend")}
                        />
                    <Form.Check 
                        type="radio"
                        label="Foe"
                        checked={galleryName === "foe"}
                        onChange={() => setGalleryName("foe")}
                        />
                </Form.Group>
            </Form.Row>
            {props.endpoint === 'enroll' ?
            <Form.Row className="text-left">
                <Form.Group>
                    <Form.Label>Name</Form.Label>
                    <FormControl
                        type="text"
                        placeholder="Subject name"
                        onChange={(e) => setName(e.target.value)}
                        value={name}
                        required
                    />
                </Form.Group>
            </Form.Row>
            : null
            }
            <Form.Row>
                <div className="input-group d-flex justify-content-center mb-3">
                    <div className="input-group-prepend">
                        <Button type="submit" variant="primary">Upload</Button>
                    </div>
                    <div className={props.type === 'file' ? "custom-file" : ''}>
                        <label className={props.type === 'file' ? "custom-file-label text-left" : 'text-center'}>{!file ? props.label : file.name}</label>
                        <input 
                            required
                            type={props.type}
                            className={props.type === 'file' ? "custom-file-input" : "form-control"}
                            placeholder={props.placeholder}
                            onChange={(e) => fileStaging(e)}
                            />
                    </div>
                </div>
            </Form.Row>
            <h2>Image Preview</h2>
            {fileSrc ? <figure><img className={classes.Image} alt="" src={fileSrc} /></figure> : <p style={{ color: "#CCC" }}>No image to preview</p>}
        </Form>
    )
}

export default ImageUploadForm

Images can now be previewed!

This is image title

5. If we add a big image it will overflow the column and take over the page. Add the following CSS to ImageUploadForm.module.css.

.Image {
    max-width: 50%
}

One of the final things that needs to be implemented is a submit function that sends the data we have added to our backend. Currently, we do not have a route set up on the backend to receive the data. Yet we can still get the submit function set up in the way that we want the backend to receive the data.

Add Submit Function

1.We will use the popular library axios to send our data to the backend. In the terminal, while in face_recognition/client install axios:

npm install axios --save

Remember, this component will be used for two kinds of data submission. We will need to create a data payload object to send as a POST request and the contents of that data object will depend on which type of form is being used to submit the data.

Thankfully, a prop is being passed in the form that distinguishes between the two types: endpoint.

The function conditionally adds the subject_id value if the endpoint prop has a value of ‘enroll’.

2. Add the handleSubmit function to ImageUploadForm.js underneath the fileStaging function.

...
   const handleSubmit = (e) => {
        e.preventDefault() // will stop the page from refreshing on submit

        // set alert variable to null

        // constructs data payload
        let data = {
            gallery_name: galleryName,
            image: fileSrc
        }

        // adds subject_id if we are enrolling a new person
        if (props.endpoint === 'enroll') {
            data = {
                ...data, // spread operater - add all the properties in the previously declared data object to this object
                subject_id: name
            }
        }

        console.log(data) // log the data to make sure that it is beng sent the way we want
        axios.post(`/api/upload/${props.endpoint}`, data)
        .then(response => {
            // set alert variable
        })
        .catch(e => {
            set alert variable
        })
    }
...

3. Add the onSubmit handler to the `` tag.

<Form onSubmit={handleSubmit} className="my-4">

Now, submit the form with data. It will fail, but it your data payload will be logged to the console.

Build Route for Uploads

In the submit function we specified a URL to send the data to (/api/upload/${props.endpoint}). We used a string literal that uses back ticks—not quotes—to dynamically change the last part of the URL. There are only two values that we are giving the ‘endpoint’ prop: ‘enroll’ and ‘recognize’.

However, we need to build those routes on the backend.

1.In the terminal navigate to face_recognition/server and run the command npm run dev. We set-up this command earlier in the example.

Listening on port 3001 should be logged to the console. The nodemon server is now listening for changes in our files. This will help us develop and catch mistakes faster.

2. In server, make a directory src and inside of that folder make another directory routes.

3. In routes, make the file upload.js and add the two routes that we talked about earlier.

// upload.js

const router = require('express').Router();

router.route('/enroll').post( async (req, res) => {
    // enroll route
})

router.route('/recognize').post( async (req, res) => {
    // recognize route
})

module.exports = router;

4. The express application does not know about this file. In server.js import the router and set up the route middleware.

// server.js
const express = require('express');
const path = require('path');
require('dotenv').config()

// Import route
const uploadRouter = require('./src/routes/upload') // NEW

// Create App
const app = express();
const port = process.env.PORT || 3001;

// Adds a parsed json body object to req
app.use(express.json({ limit: '10000kb' }));

// Set route middleware
app.use('/api/upload', uploadRouter)               // NEW

// Needed for express to find static assets
//app.use(express.static(path.resolve('client', 'build')));

// Needed so express can return an actual webpage
//app.get('*', (req, res) => {
//    res.sendFile(path.resolve('client', 'build', 'index.html'));
//});

// console.log that your server is up and running
app.listen(port, () => console.log(`Listening on port ${port}`));

Add RapidAPI Credentials and API Calls to the Route

Back in the RapidAPI marketplace, pull up the Kairos Face Recognition dashboard. Locate the two endpoints that we will use (enroll and recognize).

Notice the headers are the same in both endpoints. Furthermore, the HTTP request URL is mostly the same with the exception of the last word.

1.Pull the header information into the route and create a header object. Add another variable named baseUrl and assign it the URL section that doesn’t change between the two routes.

const router = require('express').Router();

const headers = {
    "content-type":"application/json",
    "x-rapidapi-host":"kairosapi-karios-v1.p.rapidapi.com",
    "x-rapidapi-key": process.env.KAIROS_API_KEY,
    "accept":"application/json"
}

const baseUrl = "https://kairosapi-karios-v1.p.rapidapi.com/"

router.route('/enroll').post( async (req, res) => {
...

Take note that I didn’t paste in my api-key. We are going to use the dotenv library that we installed earlier to add this

2. Create a file in the server folder named .env. Add your api-key to that file.

// .env

KAIROS_API_KEY=apikey

If we were pushing this up to a Git repository, we would add ‘.env’ to the .gitignore file so our API key isn’t public or shared among other collaborators.

3. Require the dotenv file in server.js, so our variables are loaded into the app. Underneath the imports add the line:

require('dotenv').config()

Now that we have the header object and base URL, it’s easy to build axios calls.

4. Install axios on the backend and import it into upload.js.

On the frontend, we formed the data to have key values that match what the Kairos API expects as parameter values (subject_id, gallery_name, image). This will make it easy for us to take the request body and simply place it into the request to the Kairos API.

5. Add the Kairos API calls to each route.

const router = require('express').Router();
const axios = require('axios')

router.route('/enroll').post( async (req, res) => {
    let data = {
        ...req.body
    }

    const url = baseUrl + "enroll"

    try {
        const response = await axios({ 
            "method": "POST",
            url,
            headers,
            data
        })
    } catch(e) {
        console.log(e);
        res.status(500).send();
    }
})

router.route('/recognize').post( async (req, res) => {
    let data = {
        ...req.body
    }

    const url = baseUrl + "recognize"

    try {
        const response = await axios({ 
            "method": "POST",
            url,
            headers,
            data
        })

    } catch(e) {
        console.log(e);
        res.status(500).send();
    }
})

module.exports = router;

We get the data from the front end and submit it to the Kairos API, but we don’t send any useful information back. We must inspect the response objects that we get from Kairos.

Building Useful Responses

We can test the endpoints in the RapidAPI dashboard and examine the response objects.

When we enroll a subject, and it’s successful, the response looks like:

{
   "face_id": "68267b4f16394218826",
   "images": [
     {
         "attributes": {
         // demographic information
      },
         "transaction": {
            "confidence": 0.99648, // I left this here because it's the confidence level ID that was discussed at beginning of article
         }
     }
   ],
}

If the image is low resolution, or if it does not contain a face, the response fails. The API does not return an error status, it returns an error object.

{
   "Errors":[
      {
          "ErrCode":5001
          "Message":"invalid url was sent"
      }
   ]
}

We need to check the response for the ‘Errors’ parameter, and if it exists we need to send that error back to the front end. If it succeeds, we can send back whatever information we would like to.

For the enroll endpoint, we will simply send back a nice success message.

However, the recognize response has other information we want to use. If the Kairos API recognizes a face in an image it will return a ‘candidates’ object with the subject_id of the person it recognizes.

Furthermore, if it does not recognize the face, it will not have a candidates object. Knowing this, we can build string responses that send back data in an easy to display format.

1. Insert the remaining code into upload.js. The file should have the contents below:

const router = require('express').Router();
const axios = require("axios");

const headers = {
    "content-type":"application/json",
    "x-rapidapi-host":"kairosapi-karios-v1.p.rapidapi.com",
    "x-rapidapi-key": process.env.KAIROS_API_KEY,
    "accept":"application/json"
}

const baseUrl = "https://kairosapi-karios-v1.p.rapidapi.com/"

router.route('/enroll').post( async (req, res) => {
    let data = {
        ...req.body
    }

    const url = baseUrl + "enroll"

    try {
        const response = await axios({ 
            "method": "POST",
            url,
            headers,
            data
        })

        const params = Object.keys(response.data)

        // check for errors
        if (params.includes('Errors')) {
            console.log(response.data)
            return res.status(400).send({variant:"danger", text: response.data.Errors[0].Message})
        }

        // return a simple string if the add was successful
        res.send({variant:'success', text: `Success! ${data.subject_id} added.`})
    } catch(e) {
        console.log(e);
        res.status(500).send({variant: 'danger', text: 'Server error.'});
    }
})

router.route('/recognize').post( async (req, res) => {
    let data = {
        ...req.body
    }

    const url = baseUrl + "recognize"

    try {
        const response = await axios({ 
            "method": "POST",
            url,
            headers,
            data
        })

        const params = Object.keys(response.data)

        if (params.includes('Errors')) {
            return res.status(400).send({variant: "danger", text: response.data.Errors[0].Message})
        }

        let subjects = []

        // check the response for candidates
        response.data.images.map(item => {
            console.log(item)
            if (item.candidates) {
                subjects.push(item.candidates[0].subject_id)
            }
        })

        // build string responses that contain the subjects that were found, or not found in the image
        if (subjects.length < 1) {
            return res.send({variant: "info", text: "No faces were recognized. Exercise caution."})
        }

        if (data.gallery_name === 'foe') {
            const foeString = `Be careful we recognize ${subjects.join(' ')} as foe!`

            res.send({variant: 'danger', text: foeString})
        } else {
            const friendString = `Hoozah! We recognize friends! That's ${subjects.join(' and ')}`

            res.send({variant: 'success', text: friendString})
        }
    } catch(e) {
        console.log(e);
        res.status(500).send({variant: 'danger', text: 'Server error.'});
    }
})

module.exports = router;

Create the Message Component In The Frontend

There is not a way for us to display useful messages or data on the front end. Yet, you may have noticed how we are structuring the response objects in upload.js:

{
   variant: 'danger', 
   text: 'Server error.'
}

The Message component will take in a string ‘variant’ that corresponds to allowed property values for the Alert components variant prop. The Alert component is part of the bootstrap library and can have values of ‘success’, ‘danger’, ‘primary’, ‘info’, ‘light’, ‘dark’, and a few others.

1.In components create the Message directory. Inside of that folder add the file Message.js.

2. Add the below code to Message.js

import React from 'react'
import { Alert } from 'react-bootstrap'

const message = (props) => {
    const message = props.message

    return (
        <div>
            {message && <Alert variant={props.message.variant}>{props.message.text}</Alert>}
        </div>
    )
}

export default message

It is almost time to add our subjects and test our app!

Finishing Up the ImageUploadForm

The final touches to the form component are:

  • import the Message component
  • declare a variable for the message component
  • set the variable value in the handleSubmit function, and;
  • display the message component when it has a value

The below code is what the final ImageUploadForm.js should contain.

I’ll add comments next to the lines that were added.

import React, { useState, useCallback } from 'react' 
import { Form, Button, FormControl} from 'react-bootstrap' 
import classes from './ImageUploadForm.module.css' 
import axios from 'axios' 
import Message from '../Message/Message' // NEW 

const ImageUploadForm = (props) => { 
    let [alert, setAlert] = useState(null) // NEW 
    let [file, setFile] = useState(null) 
    let [fileSrc, setFileSrc] = useState('') 
    let [galleryName, setGalleryName] = useState('friend')
    let [name, setName] = useState('')

    const fileStaging = useCallback((e) => {
        if (props.type === 'file') {
            setFile(e.target.files[0])

            let reader = new FileReader();

            try {
                reader.readAsDataURL(e.target.files[0])
            } catch (e) {
                setAlert({variant:'danger', text:'Please select valid image.'})  // NEW
                setFileSrc('')
            }

            reader.addEventListener("load", function() {
                setFileSrc(reader.result)
            }, false)
        } else {
            setFileSrc(e.target.value)
        }
    }, [props.type])

    const handleSubmit = (e) => {
        e.preventDefault()

        setAlert(null)             // NEW

        let data = {
            gallery_name: galleryName,
            image: fileSrc
        }

        if (props.endpoint === 'enroll') {
            data = {
                ...data,
                subject_id: name
            }
        }

        axios.post(`/api/upload/${props.endpoint}`, data)
        .then(response => {
            setAlert(response.data)     // NEW
        })
        .catch(e => {
            setAlert(e.response.data)   // NEW
        })
    }

    return (
        <Form onSubmit={handleSubmit} className="my-4">
            {alert && <Message message={alert} />}          // NEW
            <Form.Row className="text-left">
                <Form.Group>
                    <Form.Label>Gallery</Form.Label>
                    <Form.Text className="text-muted">
                        Select upload gallery.
                    </Form.Text>
                    <Form.Check 
                        type="radio"
                        label="Friend"
                        checked={galleryName === "friend"}
                        onChange={() => setGalleryName("friend")}
                        />
                    <Form.Check 
                        type="radio"
                        label="Foe"
                        checked={galleryName === "foe"}
                        onChange={() => setGalleryName("foe")}
                        />
                </Form.Group>
            </Form.Row>
            {props.endpoint === 'enroll' ?
            <Form.Row className="text-left">
                <Form.Group>
                    <Form.Label>Name</Form.Label>
                    <FormControl
                        type="text"
                        placeholder="Subject name"
                        onChange={(e) => setName(e.target.value)}
                        value={name}
                        required
                    />
                </Form.Group>
            </Form.Row>
            : null
            }
            <Form.Row>
                <div className="input-group d-flex justify-content-center mb-3">
                    <div className="input-group-prepend">
                        <Button type="submit" variant="primary">Upload</Button>
                    </div>
                    <div className={props.type === 'file' ? "custom-file" : ''}>
                        <label className={props.type === 'file' ? "custom-file-label text-left" : 'text-center'}>{!file ? props.label : file.name}</label>
                        <input 
                            required
                            type={props.type}
                            className={props.type === 'file' ? "custom-file-input" : "form-control"}
                            placeholder={props.placeholder}
                            onChange={(e) => fileStaging(e)}
                            />
                    </div>
                </div>
            </Form.Row>
            <h2>Image Preview</h2>
            {fileSrc ? <figure><img className={classes.Image} alt="" src={fileSrc} /></figure> : <p style={{ color: "#CCC" }}>No image to preview</p>}
        </Form>
    )
}

export default ImageUploadForm

Test

Time to use our app! To recap, we will be creating two galleries with Kairos. Kairos saves the gallery’s name once it is used and creates a new gallery if the name has not been used. What is great about that is we don’t need a database to store the subject_ids, face dimensions, or images: Kairos does that for us.

I am going to be pulling image addresses off of Google to test the app and will doing a LOTR themed testing.

First, let’s add Gollum to the ‘foe’ gallery:

This is image title

Second, upload two friends, Aragorn and Gandalf:

Third, check the gallery ‘foe’ with a different image the contains Gollum:

This is image title

Fourth, see if our app can recognize Gandalf and Aragorn in a different image:

This is image title

Conclusion

I had a lot of fun working with this API and I hope that the example app showed you how to build something even better.

Remember, there are still many ethical concerns surrounding facial recognition and they should be considered before building something that could compromise someone’s safety.

That being said, I hope you found this article helpful and leave a comment or question if you like!

Thank you for reading!

#REST API Tutorials #javascript #express.js #kairos #developer

Top 10 API Security Threats Every API Team Should Know

As more and more data is exposed via APIs either as API-first companies or for the explosion of single page apps/JAMStack, API security can no longer be an afterthought. The hard part about APIs is that it provides direct access to large amounts of data while bypassing browser precautions. Instead of worrying about SQL injection and XSS issues, you should be concerned about the bad actor who was able to paginate through all your customer records and their data.

Typical prevention mechanisms like Captchas and browser fingerprinting won’t work since APIs by design need to handle a very large number of API accesses even by a single customer. So where do you start? The first thing is to put yourself in the shoes of a hacker and then instrument your APIs to detect and block common attacks along with unknown unknowns for zero-day exploits. Some of these are on the OWASP Security API list, but not all.

Insecure pagination and resource limits

Most APIs provide access to resources that are lists of entities such as /users or /widgets. A client such as a browser would typically filter and paginate through this list to limit the number items returned to a client like so:

First Call: GET /items?skip=0&take=10 
Second Call: GET /items?skip=10&take=10

However, if that entity has any PII or other information, then a hacker could scrape that endpoint to get a dump of all entities in your database. This could be most dangerous if those entities accidently exposed PII or other sensitive information, but could also be dangerous in providing competitors or others with adoption and usage stats for your business or provide scammers with a way to get large email lists. See how Venmo data was scraped

A naive protection mechanism would be to check the take count and throw an error if greater than 100 or 1000. The problem with this is two-fold:

  1. For data APIs, legitimate customers may need to fetch and sync a large number of records such as via cron jobs. Artificially small pagination limits can force your API to be very chatty decreasing overall throughput. Max limits are to ensure memory and scalability requirements are met (and prevent certain DDoS attacks), not to guarantee security.
  2. This offers zero protection to a hacker that writes a simple script that sleeps a random delay between repeated accesses.
skip = 0
while True:    response = requests.post('https://api.acmeinc.com/widgets?take=10&skip=' + skip),                      headers={'Authorization': 'Bearer' + ' ' + sys.argv[1]})    print("Fetched 10 items")    sleep(randint(100,1000))    skip += 10

How to secure against pagination attacks

To secure against pagination attacks, you should track how many items of a single resource are accessed within a certain time period for each user or API key rather than just at the request level. By tracking API resource access at the user level, you can block a user or API key once they hit a threshold such as “touched 1,000,000 items in a one hour period”. This is dependent on your API use case and can even be dependent on their subscription with you. Like a Captcha, this can slow down the speed that a hacker can exploit your API, like a Captcha if they have to create a new user account manually to create a new API key.

Insecure API key generation

Most APIs are protected by some sort of API key or JWT (JSON Web Token). This provides a natural way to track and protect your API as API security tools can detect abnormal API behavior and block access to an API key automatically. However, hackers will want to outsmart these mechanisms by generating and using a large pool of API keys from a large number of users just like a web hacker would use a large pool of IP addresses to circumvent DDoS protection.

How to secure against API key pools

The easiest way to secure against these types of attacks is by requiring a human to sign up for your service and generate API keys. Bot traffic can be prevented with things like Captcha and 2-Factor Authentication. Unless there is a legitimate business case, new users who sign up for your service should not have the ability to generate API keys programmatically. Instead, only trusted customers should have the ability to generate API keys programmatically. Go one step further and ensure any anomaly detection for abnormal behavior is done at the user and account level, not just for each API key.

Accidental key exposure

APIs are used in a way that increases the probability credentials are leaked:

  1. APIs are expected to be accessed over indefinite time periods, which increases the probability that a hacker obtains a valid API key that’s not expired. You save that API key in a server environment variable and forget about it. This is a drastic contrast to a user logging into an interactive website where the session expires after a short duration.
  2. The consumer of an API has direct access to the credentials such as when debugging via Postman or CURL. It only takes a single developer to accidently copy/pastes the CURL command containing the API key into a public forum like in GitHub Issues or Stack Overflow.
  3. API keys are usually bearer tokens without requiring any other identifying information. APIs cannot leverage things like one-time use tokens or 2-factor authentication.

If a key is exposed due to user error, one may think you as the API provider has any blame. However, security is all about reducing surface area and risk. Treat your customer data as if it’s your own and help them by adding guards that prevent accidental key exposure.

How to prevent accidental key exposure

The easiest way to prevent key exposure is by leveraging two tokens rather than one. A refresh token is stored as an environment variable and can only be used to generate short lived access tokens. Unlike the refresh token, these short lived tokens can access the resources, but are time limited such as in hours or days.

The customer will store the refresh token with other API keys. Then your SDK will generate access tokens on SDK init or when the last access token expires. If a CURL command gets pasted into a GitHub issue, then a hacker would need to use it within hours reducing the attack vector (unless it was the actual refresh token which is low probability)

Exposure to DDoS attacks

APIs open up entirely new business models where customers can access your API platform programmatically. However, this can make DDoS protection tricky. Most DDoS protection is designed to absorb and reject a large number of requests from bad actors during DDoS attacks but still need to let the good ones through. This requires fingerprinting the HTTP requests to check against what looks like bot traffic. This is much harder for API products as all traffic looks like bot traffic and is not coming from a browser where things like cookies are present.

Stopping DDoS attacks

The magical part about APIs is almost every access requires an API Key. If a request doesn’t have an API key, you can automatically reject it which is lightweight on your servers (Ensure authentication is short circuited very early before later middleware like request JSON parsing). So then how do you handle authenticated requests? The easiest is to leverage rate limit counters for each API key such as to handle X requests per minute and reject those above the threshold with a 429 HTTP response. There are a variety of algorithms to do this such as leaky bucket and fixed window counters.

Incorrect server security

APIs are no different than web servers when it comes to good server hygiene. Data can be leaked due to misconfigured SSL certificate or allowing non-HTTPS traffic. For modern applications, there is very little reason to accept non-HTTPS requests, but a customer could mistakenly issue a non HTTP request from their application or CURL exposing the API key. APIs do not have the protection of a browser so things like HSTS or redirect to HTTPS offer no protection.

How to ensure proper SSL

Test your SSL implementation over at Qualys SSL Test or similar tool. You should also block all non-HTTP requests which can be done within your load balancer. You should also remove any HTTP headers scrub any error messages that leak implementation details. If your API is used only by your own apps or can only be accessed server-side, then review Authoritative guide to Cross-Origin Resource Sharing for REST APIs

Incorrect caching headers

APIs provide access to dynamic data that’s scoped to each API key. Any caching implementation should have the ability to scope to an API key to prevent cross-pollution. Even if you don’t cache anything in your infrastructure, you could expose your customers to security holes. If a customer with a proxy server was using multiple API keys such as one for development and one for production, then they could see cross-pollinated data.

#api management #api security #api best practices #api providers #security analytics #api management policies #api access tokens #api access #api security risks #api access keys