How to Setup Redux - Minimize Boilerplate, Speed Up Development

How to Setup Redux - Minimize Boilerplate, Speed Up Development

A guide on how to setup Redux in a generic way to facilitate up to 90% of your API calls

Motivation

I recently gave a talk at the React London Meetup on state management with Redux and I wanted to write an article explaining in more depth the architecture of the solution I proposed.

You can also find a Github repo with a full Redux setup, ready to be used in a real world React application at the end of this article, as well as a video of my talk.

The problem

Redux is an amazing library. It’s very simple and powerful at the same time. It is also very flexible. This is great because it gives us freedom to set it up the way we want and shape it to serve the needs of our application. But this flexibility also makes it difficult to integrate it for a large application because there are so many ways we can do this.

The general consensus on how to setup Redux to do an api call is to:

  • Declare constants (REQUEST_ACTION, REQUEST_ACTION, REQUEST_ACTION)
  • Create an action creator which will be responsible to dispatch the request action
  • Use an API service to call endpoint (Using a third party library like redux-thunk, saga, observables to enable that)
  • Receive a payload. If successful, dispatch REQUEST_ACTION, if not then dispatch REQUEST_ACTION
  • Handle payload in reducer
  • Connect redux to react to the component (using REQUEST_ACTION and REQUEST_ACTION)

And this has to be repeated for **every single **API call. This quickly results in a lot of repeated boilerplate and unmaintainable code.

Solution

Let’s see how we can solve the problem described above by following an example to read a single user.

Action Creators

Now the first thing we would typically do if we wanted to read a user would be declare some constants as below:

export const REQUEST_READ_USER = 'REQUEST_READ_USER';
export const SUCCESS_READ_USER = 'SUCCESS_READ_USER';
export const FAIL_READ_USER = 'FAIL_READ_USER';

The first improvement we are going to do is to completely get rid of these! We don’t really need to declare them as constants. We can easily compute them dynamically and with a few unit tests make sure that everything works as expected.

The next thing we would typically do would be to define an action creator like so:

This action creator uses redux-thunk to first send a REQUEST_ACTION action, then does the API call and fires a REQUEST_ACTION or REQUEST_ACTION action depending on the response. But there are two problems with this code:

  1. This action creator is very specific to the REQUEST_ACTION entity. The functionality for reading entities will be mostly the same so defining an action creator for just the user only is not very reusable. If we wanted to read a group entity for example the code would be almost identical.
  2. We are mixing concerns by firing both the request action but also doing the api call. The action creator should just be responsible for sending an action.

Let’s see how we can fix these problems. The action creator was re-written in a way that its sole responsibility is to fire a REQUEST_ACTION action. At the same time it is now able to be used for any entity in the system. This is how it looks like:

As you can see by the name of this action creator, it is generic (as opposed to REQUEST_ACTION in the previous section). It can be used by any entity in the system. This action creator takes two arguments: The REQUEST_ACTION (this could be REQUEST_ACTION , REQUEST_ACTION , REQUEST_ACTION e.t.c) and the ID of the entity we want to read. This action creator is firing an action with the following fields:

  1. The type, which will be REQUEST_ACTION (We are making REQUEST_ACTION uppercase just for uniformity)
  2. The REQUEST_ACTION, which will hold the parameters that we will use to compute the API endpoint we will call.
  3. The meta data, which will be used by our reducers and middlewares.

So what we’ve achieved here is to create an action creator that works with any entity in the system, the type is computed dynamically so we don’t need constants any more and also it’s only purpose is to return an action.

API Middleware

Next we want to create an API middleware where we will put all the logic for sending the API call and then dispatching a success or fail action depending on the response.

And this is what it will look like:

Here we are listening on any action that its type starts with REQUEST_ACTION (e.g. REQUEST_ACTION ), then we are calling the API endpoint and depending on the response firing a REQUEST_ACTION or REQUEST_ACTION action.

The two thing to note here are:

  1. The REQUEST_ACTION which were defined in the request action in the previous section are used to compute the api endpoint.
  2. The action type is again computed dynamically.

So, this API middleware works for any entity in the system, eliminates the action type constants and the use of any external libraries to enable us to do our API calls.

Normalization Middleware

Next we should normalize the response we get from the API. Before we see how we can do this let’s see what normalization is:

Many applications deal with data that is nested or relational in nature. An example is shown below:

Payload with nested data (before normalization)

This is a REQUEST_ACTION entity, which has an author and some comments (which themselves have an author).

With normalization we can return the nested entities with their IDs, gathered in dictionaries. Below you can see the normalized version of the REQUEST_ACTION .

Normalized Payload

All nested data now refer to an entity through the REQUEST_ACTION key.

There is a major benefit to normalize data in that updating becomes very easy. If for example we change the name of the user with REQUEST_ACTION 1 from ‘Jeff’ to ‘Peter’ then with the first approach we need to update it in 2 places. But with the normalized data we only need to update it in one place. You can see how the first approach can become unmaintainable in a large application. In the unnormalized version we could end up with a situation of having to update the state in 20 different places!

The middleware to normalize the payload will look like this:

Here we are listening on any action that its type starts with REQUEST_ACTION (e.g. REQUEST_ACTION ) and then normalizing the payload data.

Note: For all of our normalization needs, we will use the normalizr library

Reducers - Store structure

This is how we are going to structure our store:

All the data coming from our api will live under the REQUEST_ACTION key. Under there we will keep a key for every entity in the system (e.g. REQUEST_ACTION, REQUEST_ACTION e.t.c).

Under each entity key we will have:

  1. A REQUEST_ACTION key where we will keep the payload coming back from our API (in a normalized structure).
  2. A REQUEST_ACTION key where we will keep the status of the api calls.

To achieve this we will need a reducer creator. A reducer creator is a function that takes an argument and returns reducers as shown below:

This REQUEST_ACTION reducer creator takes the REQUEST_ACTION argument and returns two reducers (using the REQUEST_ACTION function of REQUEST_ACTION library).

Important Note:

We will have to call this reducer creator for every entity in the system. So every entity will have its own REQUEST_ACTION and REQUEST_ACTION reducer. This is important to understand as we explain how the reducers work. Every redux action goes through all the reducers. What that means is that in every REQUEST_ACTION and every REQUEST_ACTION reducer we would have to only consider the action types or action payload that is relevant to the entity that this reducer corresponds to. It’s also a good idea to see the Github repo (at the end of this article) in order to fully understand how these reducers work.

byId Reducer

The REQUEST_ACTION reducer will listen on any action type that starts with REQUEST_ACTION (e.g. REQUEST_ACTION ) and if in our payload there is data of this entity type, it will be merged in the state. If for example our payload looks like the data in the Normalized Payload above and this is the REQUEST_ACTION reducer of the REQUEST_ACTION entity the comment part of the payload will be merged into the state.

readIds Reducer

Here we are listening to any action that it’s type starts with REQUEST_ACTION and that is the relevant REQUEST_ACTION reducer. If for example the action is REQUEST_ACTION and this is the REQUEST_ACTION reducer of the REQUEST_ACTION entity we will go ahead and update the state.

Connect Higher Order Component

The last thing I want to do is to reduce the boilerplate when I’m connecting my redux code with my react code. Typically in every React component we wanted to connect with redux we would have to use the connect library of REQUEST_ACTION and then define a REQUEST_ACTION and a REQUEST_ACTION function to achieve this. In order to achieve reusability I want to move this code in a higher order component (HOC) that will look something like this:

export const REQUEST_READ_USER = 'REQUEST_READ_USER';
export const SUCCESS_READ_USER = 'SUCCESS_READ_USER';
export const FAIL_READ_USER = 'FAIL_READ_USER';

This HOC received two arguments. The REQUEST_ACTION and an REQUEST_ACTION . It then passes to our children 3 arguments:

  1. A read function which calls the REQUEST_ACTION action creator we saw in the previous sections.
  2. The REQUEST_ACTION which is the data selected from the relevant REQUEST_ACTION reducer.
  3. The REQUEST_ACTION which is the status of the api call selected from the relevant REQUEST_ACTION reducer.

And this HOC can be used like this:

export const REQUEST_READ_USER = 'REQUEST_READ_USER';
export const SUCCESS_READ_USER = 'SUCCESS_READ_USER';
export const FAIL_READ_USER = 'FAIL_READ_USER';

In line 22 we are implementing the HOC seen above. We pass the two required arguments. The REQUEST_ACTION , which in this case it will be REQUEST_ACTION as we want to read a user. And the REQUEST_ACTION which in this case is REQUEST_ACTION as we want to read the user with id 1.

The HOC gives us the three arguments (read, status, entity). Then in our REQUEST_ACTION component we can call REQUEST_ACTION when the component mounts. We can also use the status to see if the api call has finished. If it has then we show the user name otherwise we can show a REQUEST_ACTION text.

Here we can see how much we have reduced the boilerplate in our react components. The only thing we need to connect react with redux and do a read api call is to use this HOC.

Recap

  1. We got rid of the action type constants
  2. We defined a generic readEntity action creator that can be used by any entity in the system and its sole responsibility is to fire the request action.
  3. We defined an **api middleware **to call our endpoint and fire success or fail action depending on the response.
  4. We defined a **normalize middleware **responsible to normalize our payload.
  5. We defined a getReducers reducer creator that return two sub-reducers byId and readIds
  6. We moved the logic to connect our react components with redux in a Higher Order Component.

Achieve 90% coverage (or more)

It’s important to notice that all the code above is very generic. That means that we can read any entity in the system without writing any additional code. But to achieve 90% or more coverage of our api call needs we have to handle all the following cases:

  1. Create
  2. Read
  3. Update
  4. Delete
  5. Attach or detach an entity from another in a many to many relationship.

And we have to allow for single or multiple entities (e.g. we should be able to read a single user or multiple users, or delete one post or multiple posts at once).

And actually in order to achieve this there is not a lot of additional code needed.

You can find the entire codebase in the Github repo below.

This repo serves as a guide on how to setup Redux in a generic way. It’s an MIT licensed repo so feel free to use it as is, fork it or use it as an inspiration.

How to Implement Redux in 24 Lines of JavaScript?

How to Implement Redux in 24 Lines of JavaScript?

Redux is among the most important JavaScript libraries ever created. In this posr, you'll learn how to Implement Redux in 24 lines of JavaScript. Inspired by prior art like [Flux](https://facebook.github.io/flux/) and...

Redux is among the most important JavaScript libraries ever created. In this posr, you'll learn how to Implement Redux in 24 lines of JavaScript.

Inspired by prior art like Flux and Elm, Redux put JavaScript functional programming on the map by introducing a scalable architecture of three simple points.

If you're new to Redux, consider reading the official docs first.

Redux Is Mostly Convention

Consider this simple counter application that uses the Redux architecture. If you'd like to jump ahead check out the Github repo for it.

State lives in a single tree

The application's state looks like this.

const initialState = { count: 0 };

Actions declare state changes

By Redux convention, I do not directly modify (mutate) the state.

// DON'T do this in a Redux app
state.count = 1;

Instead I create all the actions the user may leverage in the application.

const actions = {
  increment: { type: 'INCREMENT' },
  decrement: { type: 'DECREMENT' }
};

Reducer interprets action and updates state

The last architectural piece calls for a reducer, a pure function that returns a new copy of your state based on the previous state and action.

  • If increment is fired, increment state.count.
  • If decrement is fired, decrement state.count.
const countReducer = (state = initialState, action) => {
  switch (action.type) {
    case actions.increment.type:
      return {
        count: state.count + 1
      };

    case actions.decrement.type:
      return {
        count: state.count - 1
      };

    default:
      return state;
  }
};

No Redux so far

Did you notice that we haven't touched the Redux library yet? We've just created some objects and a function. This is what I mean by "mostly convention", 90% of Redux doesn't require Redux!

Let's implement Redux

To put this architecture to use, we must plug it into a store. We'll implement just one function–createStore.

It's used like this.

import { createStore } from 'redux'

const store = createStore(countReducer);

store.subscribe(() => {
  console.log(store.getState());
});

store.dispatch(actions.increment);
// logs { count: 1 }

store.dispatch(actions.increment);
// logs { count: 2 }

store.dispatch(actions.decrement);
// logs { count: 1 }

And here's our initial boilerplate. We'll need a list of listeners and the initial state supplied by the reducer.

const createStore = (yourReducer) => {
    const listeners = [];
    let currentState = yourReducer(undefined, {});
}

Whenever someone subscribes to our store, they get added to the listeners array. The is important because every time someone dispatches an action, all the listeners must be notified in a loop.

Calling yourReducer with undefined and an empty object returns the initialState we installed up above. This gives us a proper value to return when we call store.getState(). Speaking of which, let's create that method.

store.getState()

This is a function that returns the latest state from the store. We'll need this to update our UI every time the user clicks a button.

const createStore = (yourReducer) => {
    const listeners = [];
    let currentState = yourReducer(undefined, {});

    return {
        getState: () => currentState
    };
}

store.dispatch(action)

This is a function that takes an action as a parameter. It feeds that action and the currentState to yourReducer to get a new state. Then dispatch notifies everyone subscribed to the store.

const createStore = (yourReducer) => {
  const listeners = [];
  let currentState = yourReducer(undefined, {});

  return {
    getState: () => currentState,
    dispatch: (action) => {
      currentState = reducer(currentState, action);

      listeners.forEach((listener) => {
        listener();
      });
    }
  };
};

store.subscribe(listener)

This is a function that lets you be notified when the store receives an action It's good to use store.getState() in here to get your latest state and update your UI.

const createStore = (yourReducer) => {
  const listeners = [];
  let currentState = yourReducer(undefined, {});

  return {
    getState: () => currentState,
    dispatch: (action) => {
      currentState = reducer(currentState, action);

      listeners.forEach((listener) => {
        listener();
      });
    },
    subscribe: (newListener) => {
      listeners.push(newListener);

      const unsubscribe = () => {
        listeners = listeners.filter((l) => l === newListener);
      };

      return unsubscribe;
    }
  };
};

subscribe returns a function called unsubscribe that you can call when you're no longer interested in listening to the store's updates.

All Together Now

Let's hook this up to our buttons and view the final source code.

// simplified createStore function
const createStore = (reducer) => {
  const listeners = [];
  let currentState = reducer(undefined, {});

  return {
    getState: () => currentState,
    dispatch: (action) => {
      currentState = reducer(currentState, action);

      listeners.forEach((listener) => {
        listener();
      });
    },
    subscribe: (newListener) => {
      listeners.push(newListener);

      const unsubscribe = () => {
        listeners = listeners.filter((l) => l === newListener);
      };

      return unsubscribe;
    }
  };
};

// Redux architecture pieces
const initialState = { count: 0 };

const actions = {
  increment: { type: 'INCREMENT' },
  decrement: { type: 'DECREMENT' }
};

const countReducer = (state = initialState, action) => {
  switch (action.type) {
    case actions.increment.type:
      return {
        count: state.count + 1
      };

    case actions.decrement.type:
      return {
        count: state.count - 1
      };

    default:
      return state;
  }
};

const store = createStore(countReducer);

// DOM elements
const incrementButton = document.querySelector('.increment');
const decrementButton = document.querySelector('.decrement');

// Wire click events to actions
incrementButton.addEventListener('click', () => {
  store.dispatch(actions.increment);
});

decrementButton.addEventListener('click', () => {
  store.dispatch(actions.decrement);
});

// Initialize UI display
const counterDisplay = document.querySelector('h1');
counterDisplay.innerHTML = parseInt(initialState.count);

// Update UI when an action fires
store.subscribe(() => {
  const state = store.getState();

  counterDisplay.innerHTML = parseInt(state.count);
});

And once again here's our final UI.

If you're interested in the HTML/CSS I used, here's the GitHub repo again!

Thanks for reading

Redux Basics

Redux Basics

In this post, the simplest React Redux tutorial I wish I had when I started learning. ... Having seen the basics let's now talk about what problem Redux tries to solve.

Throughout last week, I had my first taste of Redux. During this time, we implemented Redux with React but, it does not need to be used exclusively with React. However, this has been my only experience with it thus far, so I will explain it the way it is used with React.

Upon introduction to Redux, you may be left feeling instantly confused. Initially learning React, most days are spent getting comfortable with the idea of passing props from one component, to another, to another... to another.... to.... another.

While this is an easy concept to understand, it's not necessarily the most efficient. There are a variety of state management systems used within React, but I want to discuss Redux and what has helped me wrap my mind around it!

You may also like: Angular vs React vs Vue: Which one will be popular in 2020.

What is Redux?

Redux has one main advantage, and that's the efficiency it provides. Redux allows you to store your state in what is called a "Redux Store" and uses actions to call reducers, which in turn manipulate your state however you see fit.

Let's keep this simple and straight to the point. Redux is Uber Eats.

I know what you may be thinking... What are you are talking about? Let me explain.

In traditional prop passing, relate each component to a neighbor. If you needed something from the grocery store, imagine that you have to ask neighbor E, to ask neighbor D, to ask neighbor C, to ask neighbor B, to ask neighbor A, if you can use some of their bread. It works... but, it's pretty inconvenient

What if there was a way to just have the bread delivered straight to you?!

AH, this is where Redux shines. With the use of the Redux store, that bread (AKA state), is always available whenever you need it. No passing props, no talking to neighbors, just simply call up the store and get what you need!

The Redux Store

The Redux Store takes about 3.87 seconds to build, and is one of the easiest things to do in React. After installing Redux with your package manager of choice, simply import the function into your main component (usually index.js).

import { createStore } from 'redux'

Boom! Now you have the power, just create a store really quick! Be sure to export your reducer from it's proper file, and import it into your index.js file.

const store = createStore(yourReducerGoesHere)

Simple enough? Now your store exists in a variable called store. It takes in a reducer as well.(This is how it will manipulate the state that's held within the store. Now, let's talk about the Provider.

Providing state to your components

Provider is simple enough to remember, because it provides access the state from the store to your components. I say access, because it doesn't necessarily give your components the state just yet (this is what we have connect() for).

In that same component, you'll want to import Provider.

import { Provider } from 'react-redux' Booyah!

After that, you want to wrap your App component in that provider. Think of this as granting your application the ability to use the store. It typically looks something like this:

ReactDOM.render(
<Provider store={store}>
    <App />
</Provider>
, document.getElementById("root"));

See that sneaky little prop pass, right there? It almost forms a sentence! In the Provider we passed in the store. It can almost be read as, "Providing the store to the component". Well, that's how I read it at least! :)

Awesome, now we created a store, passed the store to the provider, which is providing that store to our application. Before seeing how we grab the state, we need to have state first! On to the reducer!

Reducing The Stress

Reducers! This is one of the powerful aspects of Redux. Essentially, I call them the execution guidelines. The reducer file will typically consist of two things: the initial state, and the reducer itself.

For example, for simplicity sake, let's say our initial state has an array of names.

const initialState = {
   names: ['Bob', 'Susan']
}

Woo! They are looking great. Now the reducer comes into play. This section can get messy, so we'll keep it extremely simple. Reducers are functions full of if...else conditions. The easier way to write this is with switch cases. To prevent confusion, I'll provide an example of both, if...else and a switch case, if you happen to be familiar with both!

Our case that modifies state will be called, 'Add Name'. However, in Redux cases, it's common practice to use all capital letters for this (kind of similar to just screaming at the reducer to do its job), so it would look like 'ADD_NAME'.

If none of the cases do match, you want to be sure to return the initialState. I know this is a lot of words, so let's see an example!

export const reducer = (state = initialState, action) {
    if (action.type === 'ADD_NAME') {
        return {
            ...state,
            names: [...names, action.payload]
        }
    } else {
        return state
    }
}

What's happening here is the reducer takes in state, and an action. State will be undefined if you don't provide it an initial state, so in this example, we assign state to initialState. The action will be an object containing a type and sometimes a payload property. For example, this action object for this example may look like:

{ type: 'ADD_NAME', payload: newNameGoesHere }

The type specifies what reducer case to trigger, like instructions! The payload is just data, it can be called anything. In this case, we have a new name we want to add to the users array. So we spread the whole state object first, then spread the users array into a new array, and add the new name on to the end, this name is being referenced by the action.payload.

So back to my point, reducers are the execution guidelines. They take instruction from the action, and perform based on what action.type is called. This will make more sense in a second when we discuss actions. The payload property is just a common way of passing in the data you want to incorporate into state, it can be called anything - beanChili if you want! :D

Like I said, reducers are typically written in a switch case format, so they may look like this when you come across them:

export const reducer = (state = initialState, action) {
    switch(action.type){
        case 'ADD_NAME':
            return {
                ...state,
                names: [...names, action.payload]
            }
        default:
            return state
    }
}

This achieves the same result, just tends to be less words, the longer your code gets!

Okay, so we've covered the store, the provider, initial state, and the reducer. Now let's take a peek at actions!

Lights, Camera, ACTIONS

As I stated earlier, actions are the instructions for the reducer. Action creators are functions, that return actions. These actions are objects similar to the one I referenced above, with a type and a payload property.

The way these work, is your action creator function is called within your component, which returns an object of "instructions". In this case, you call the action, and it will return an object that looks like:

{ type: 'ADD_NAME', payload: newName }

This function could be represented by:

export const addName = (newName) => {
   return { type: 'ADD_NAME', payload: newName }
}

In this case, when the addName function is invoked, we will pass in the name we want to add, as newName!

Now, this returned object gets passed into the reducer. Can you tell what's going to happen?

The reducer enters the switch case, and checks the action.type. OH! The type is 'ADD_NAME', so hop into that return statement.

Okay, so it is returning state, and then attaching action.payload onto the enter of the array... what is action.payload?

Well, referencing our object above, we see action.payload is the newName. Let's say that we passed in the name 'Chris' as the newName argument. What happens now, is Chris is tacked onto the end of the array. Now our users array in state looks like:

['Bob', 'Susan', 'Chris'] Awesome!

So essentially we just called a function (an action creator), which said, "Hey Reducer... add a new name, the new name is Chris!"

The reducer responds, "Cool, added the name, here's your new state!"

Simple enough, right? They definitely get more complex as more functionality is incorporated into your application, but these are the basics.

However, there is one final question:

How do the components actually access this state?

Simple! By connect! Let's take a look.

Connecting the links

Connecting the store state to our components becomes a bit of extra work, but essentially we have our state, and provide access to the main component (App.js). However, now we need to accept access, via the connect() method.

Connect is a higher-order component, which is a different topic itself, but essentially this gets invoked twice in a row. It is called during the export of your component.

First, let's import connect into our component:

import { connect } from 'react-redux';

Say we have a <List /> component being rendered in App.js, and we want to connect List.js. In that component, on the export line we could do something like:

export default connect(null, {})(List);

The first invocation takes in two items, the state you're receiving, and the actions you want to use (in that order). Let's touch on the state.

Remember, connecting only accepts access, it doesn't actually provide the state, that's what we have mapStateToProps for. :D

mapStateToProps says, "Oh, you connected your component? You granted access? Well here is the state you asked for!"

Okay... Maybe the component doesn't talk, but if they did, they'd probably say something along those lines.

This mapStateToProps example, is a function that receives the state, and is then passed into the connect method. Like this:

const mapStateToProps = state => {
   return {
      names: state.names 
   }
}

This function takes in state, which is the entire state object from the reducer. In this case, our state object only has one array inside of it, but these state objects are typically 10x as long, so we have to specify what information we want!

In this return line, we say, "Return an object with a names property." How do we know what names is? Well, we access it off of the state object, by state.names.

Our returned property doesn't need to be called names, we could do something like:

const mapStateToProps = state => {
   return {
      gummyBears: state.names
   }
}

But, that's not very semantic is it? We want to understand that names is an array of names. So it's common practice to keep the same property name, in your returned state object!

We're almost finished, so hang in there! Let's recap where we're at.

We have our component accessing state from the store, through mapStateToProps. The state exists in the component now, but the component can't access it just yet.

First, we need to pass it to the connect function. The connect functions says, "Access to the store granted! Now... what state am I granting access to?"

So we pass in the function returning state, mapStateToProps, like this:

export default connect(mapStateToProps, {})(List) Radical!

We're almost there!

Now the component is capable of receiving that state as props, like it traditionally would from a parent component. Maybe we are mapping over it, and displaying each name on the screen in a div. Here's what this may look like!

const List = props => {
    return (
        <div>
            {
                props.names.map(name => {
                    return <div>{name}</div>
                })
            }
        </div>
    )
}

Awesome! But there is one final problem... Where does the action get called?

Typically there would be an input, so you could input a new name, and add it to the array - but, for simplicity sake, let's just add a button that adds the name Chris, when clicked! (Not very functional, but you see my point! :D)

We need to access that action creator function. Well, earlier we exported that function so we could import it where we need it, like in our List.js component!

import { addName } from "../actions"

The file location will depend on your directory structure, but it is common to have all actions exported from an index.js file in your actions directory, and then import from that directory. Don't worry too much about that now though!

Great, we have our function, but we can't just pass this function as props to our component just yet. This action is related to Redux, and with Redux we need to connect the action through the connect higher-order component, so when we return our action object, our reducer can accept it and perform accordingly!

Remember that extra space in the connect at the bottom of our List.js component? Let's fill that in with our addName function.

export default connect(mapStateToProps, {addName})(List);

Now, we can pass in our function as props (similar to our state), and use the function as we need!

const List = props => {
    return (
        <div>
            <button onClick={() => props.addName('Chris')}></button>
            {
                props.names.map(name => {
                    return <div>{name}</div>
                })
            }
        </div>
    )
}

I simply created a button, and added an onClick event listener, which triggers the addName function, and passing in 'Chris', like we set out to achieve!

Geez! that was a mission... but we made it! So, let's recap what is happening exactly.

The Redux Recap

We started with creating our store, and passed access to it through the provider, which wrapped our application. Then we created our initial state to use, and formed our reducer which manipulates the state. We built an action creator, addName which is a function that returns instructions for the reducer. These specific instructions said, "We want to add the name Chris to the names array!"

The reducer then takes that information and adds the name to the state. Our component accesses the state through connect, and receives the state through the mapStateToPropsfunction. We also import our action creator, addName, and pass it to connect as well.

The result? We can access our action creator, and our state, as props! However, we aren't passing this information through any other components, just pulling it directly from the store. Delivery straight to your door! Uber eats roc- I mean, Redux rocks!

I understand there is so much more to Redux, and many other things you can change to make everything easier and simpler to use, I just wanted to cover some of the basic foundations of it, and what has helped me understand it a bit better!

I would love to hear your thoughts/opinions on Redux. Thank you for reading !

Full-Stack JavaScript Tutorial for Beginners

Full-Stack JavaScript Tutorial for Beginners

Learn full-stack web development using JavaScript (ReactJS, NodeJS, LoopbackJS, Redux and Material-UI)!

Get started as a full-stack JavaScript developer with this 2.5 hour tutorial for beginners!

In this video we will get started with NodeJS and move onto a React development project. This video is a 2.5 free preview pulled from The Complete Full-Stack JavaScript Course on Udemy. If you enjoy this video feel free to checkout the complete course. https://learnstartup.net/p/nMA3zKCMO

Time Stamps

00:41 Intro to the Course

11:59 NodeJS Environment Setup

24:24 Breaking Down a ReactJS Project

37:33 Writing a React Component

46:24 The React Lifecycle

51:19 The React State

1:06:35 Understanding Component Props and Re-rendering

1:24:12 Importing CSS into React Components

1:28:48 Calculator Project Part 1

1:47:30 Calculator Project Part 2

Thanks for reading

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Further reading

JavaScript Programming Tutorial - Full JavaScript Course for Beginners

New ES2019 Features Every JavaScript Developer Should Know

Best JavaScript Frameworks, Libraries and Tools to Use in 2019

JavaScript Basics Before You Learn React

Build a CMS with Laravel and Vue

Google’s Go Essentials For Node.js / JavaScript Developers