1559943720
Working with Data and APIs in JavaScript - Saving Images and Base64 Encoding
Welcome to Working with Data and APIs in JavaScript!
This course is for aspiring developers who want to learn how to work with data in web applications and the basics of server-side programming with Node. How do you retrieve, collect, and store data? The course will be taught through a series of creating three data projects.
Let’s add an image from the webcam to our database. For this project, we will be using the p5.js JavaScript library!
#javascript #web-development #node-js #api
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Buddha Community
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EasyMDE: Simple, Beautiful and Embeddable JavaScript Markdown Editor
EasyMDE - Markdown Editor
This repository is a fork of SimpleMDE, made by Sparksuite. Go to the dedicated section for more information.
A drop-in JavaScript text area replacement for writing beautiful and understandable Markdown. EasyMDE allows users who may be less experienced with Markdown to use familiar toolbar buttons and shortcuts.
In addition, the syntax is rendered while editing to clearly show the expected result. Headings are larger, emphasized words are italicized, links are underlined, etc.
EasyMDE also features both built-in auto saving and spell checking. The editor is entirely customizable, from theming to toolbar buttons and javascript hooks.
Quick access
Install EasyMDE
Via npm:
npm install easymde
Via the UNPKG CDN:
<link rel="stylesheet" href="https://unpkg.com/easymde/dist/easymde.min.css">
<script src="https://unpkg.com/easymde/dist/easymde.min.js"></script>
Or jsDelivr:
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/easymde/dist/easymde.min.css">
<script src="https://cdn.jsdelivr.net/npm/easymde/dist/easymde.min.js"></script>
How to use
Loading the editor
After installing and/or importing the module, you can load EasyMDE onto the first textarea element on the web page:
<textarea></textarea>
<script>
const easyMDE = new EasyMDE();
</script>
Alternatively you can select a specific textarea, via JavaScript:
<textarea id="my-text-area"></textarea>
<script>
const easyMDE = new EasyMDE({element: document.getElementById('my-text-area')});
</script>
Editor functions
Use easyMDE.value() to get the content of the editor:
<script>
easyMDE.value();
</script>
Use easyMDE.value(val) to set the content of the editor:
<script>
easyMDE.value('New input for **EasyMDE**');
</script>
Configuration
Options list
- autoDownloadFontAwesome: If set to
true, force downloads Font Awesome (used for icons). If set tofalse, prevents downloading. Defaults toundefined, which will intelligently check whether Font Awesome has already been included, then download accordingly. - autofocus: If set to
true, focuses the editor automatically. Defaults tofalse. - autosave: Saves the text that's being written and will load it back in the future. It will forget the text when the form it's contained in is submitted.
- enabled: If set to
true, saves the text automatically. Defaults tofalse. - delay: Delay between saves, in milliseconds. Defaults to
10000(10 seconds). - submit_delay: Delay before assuming that submit of the form failed and saving the text, in milliseconds. Defaults to
autosave.delayor10000(10 seconds). - uniqueId: You must set a unique string identifier so that EasyMDE can autosave. Something that separates this from other instances of EasyMDE elsewhere on your website.
- timeFormat: Set DateTimeFormat. More information see DateTimeFormat instances. Default
locale: en-US, format: hour:minute. - text: Set text for autosave.
- enabled: If set to
- autoRefresh: Useful, when initializing the editor in a hidden DOM node. If set to
{ delay: 300 }, it will check every 300 ms if the editor is visible and if positive, call CodeMirror'srefresh(). - blockStyles: Customize how certain buttons that style blocks of text behave.
- bold: Can be set to
**or__. Defaults to**. - code: Can be set to
```or~~~. Defaults to```. - italic: Can be set to
*or_. Defaults to*.
- bold: Can be set to
- unorderedListStyle: can be
*,-or+. Defaults to*. - scrollbarStyle: Chooses a scrollbar implementation. The default is "native", showing native scrollbars. The core library also provides the "null" style, which completely hides the scrollbars. Addons can implement additional scrollbar models.
- element: The DOM element for the
textareaelement to use. Defaults to the firsttextareaelement on the page. - forceSync: If set to
true, force text changes made in EasyMDE to be immediately stored in original text area. Defaults tofalse. - hideIcons: An array of icon names to hide. Can be used to hide specific icons shown by default without completely customizing the toolbar.
- indentWithTabs: If set to
false, indent using spaces instead of tabs. Defaults totrue. - initialValue: If set, will customize the initial value of the editor.
- previewImagesInEditor: - EasyMDE will show preview of images,
falseby default, preview for images will appear only for images on separate lines. - imagesPreviewHandler: - A custom function for handling the preview of images. Takes the parsed string between the parantheses of the image markdown
as argument and returns a string that serves as thesrcattribute of the<img>tag in the preview. Enables dynamic previewing of images in the frontend without having to upload them to a server, allows copy-pasting of images to the editor with preview. - insertTexts: Customize how certain buttons that insert text behave. Takes an array with two elements. The first element will be the text inserted before the cursor or highlight, and the second element will be inserted after. For example, this is the default link value:
["[", "](http://)"].- horizontalRule
- image
- link
- table
- lineNumbers: If set to
true, enables line numbers in the editor. - lineWrapping: If set to
false, disable line wrapping. Defaults totrue. - minHeight: Sets the minimum height for the composition area, before it starts auto-growing. Should be a string containing a valid CSS value like
"500px". Defaults to"300px". - maxHeight: Sets fixed height for the composition area.
minHeightoption will be ignored. Should be a string containing a valid CSS value like"500px". Defaults toundefined. - onToggleFullScreen: A function that gets called when the editor's full screen mode is toggled. The function will be passed a boolean as parameter,
truewhen the editor is currently going into full screen mode, orfalse. - parsingConfig: Adjust settings for parsing the Markdown during editing (not previewing).
- allowAtxHeaderWithoutSpace: If set to
true, will render headers without a space after the#. Defaults tofalse. - strikethrough: If set to
false, will not process GFM strikethrough syntax. Defaults totrue. - underscoresBreakWords: If set to
true, let underscores be a delimiter for separating words. Defaults tofalse.
- allowAtxHeaderWithoutSpace: If set to
- overlayMode: Pass a custom codemirror overlay mode to parse and style the Markdown during editing.
- mode: A codemirror mode object.
- combine: If set to
false, will replace CSS classes returned by the default Markdown mode. Otherwise the classes returned by the custom mode will be combined with the classes returned by the default mode. Defaults totrue.
- placeholder: If set, displays a custom placeholder message.
- previewClass: A string or array of strings that will be applied to the preview screen when activated. Defaults to
"editor-preview". - previewRender: Custom function for parsing the plaintext Markdown and returning HTML. Used when user previews.
- promptURLs: If set to
true, a JS alert window appears asking for the link or image URL. Defaults tofalse. - promptTexts: Customize the text used to prompt for URLs.
- image: The text to use when prompting for an image's URL. Defaults to
URL of the image:. - link: The text to use when prompting for a link's URL. Defaults to
URL for the link:.
- image: The text to use when prompting for an image's URL. Defaults to
- uploadImage: If set to
true, enables the image upload functionality, which can be triggered by drag and drop, copy-paste and through the browse-file window (opened when the user click on the upload-image icon). Defaults tofalse. - imageMaxSize: Maximum image size in bytes, checked before upload (note: never trust client, always check the image size at server-side). Defaults to
1024 * 1024 * 2(2 MB). - imageAccept: A comma-separated list of mime-types used to check image type before upload (note: never trust client, always check file types at server-side). Defaults to
image/png, image/jpeg. - imageUploadFunction: A custom function for handling the image upload. Using this function will render the options
imageMaxSize,imageAccept,imageUploadEndpointandimageCSRFTokenineffective.- The function gets a file and
onSuccessandonErrorcallback functions as parameters.onSuccess(imageUrl: string)andonError(errorMessage: string)
- The function gets a file and
- imageUploadEndpoint: The endpoint where the images data will be sent, via an asynchronous POST request. The server is supposed to save this image, and return a JSON response.
- if the request was successfully processed (HTTP 200 OK):
{"data": {"filePath": "<filePath>"}}where filePath is the path of the image (absolute ifimagePathAbsoluteis set to true, relative if otherwise); - otherwise:
{"error": "<errorCode>"}, where errorCode can benoFileGiven(HTTP 400 Bad Request),typeNotAllowed(HTTP 415 Unsupported Media Type),fileTooLarge(HTTP 413 Payload Too Large) orimportError(see errorMessages below). If errorCode is not one of the errorMessages, it is alerted unchanged to the user. This allows for server-side error messages. No default value.
- if the request was successfully processed (HTTP 200 OK):
- imagePathAbsolute: If set to
true, will treatimageUrlfromimageUploadFunctionand filePath returned fromimageUploadEndpointas an absolute rather than relative path, i.e. not prependwindow.location.originto it. - imageCSRFToken: CSRF token to include with AJAX call to upload image. For various instances like Django, Spring and Laravel.
- imageCSRFName: CSRF token filed name to include with AJAX call to upload image, applied when
imageCSRFTokenhas value, defaults tocsrfmiddlewaretoken. - imageCSRFHeader: If set to
true, passing CSRF token via header. Defaults tofalse, which pass CSRF through request body. - imageTexts: Texts displayed to the user (mainly on the status bar) for the import image feature, where
#image_name#,#image_size#and#image_max_size#will replaced by their respective values, that can be used for customization or internationalization:- sbInit: Status message displayed initially if
uploadImageis set totrue. Defaults toAttach files by drag and dropping or pasting from clipboard.. - sbOnDragEnter: Status message displayed when the user drags a file to the text area. Defaults to
Drop image to upload it.. - sbOnDrop: Status message displayed when the user drops a file in the text area. Defaults to
Uploading images #images_names#. - sbProgress: Status message displayed to show uploading progress. Defaults to
Uploading #file_name#: #progress#%. - sbOnUploaded: Status message displayed when the image has been uploaded. Defaults to
Uploaded #image_name#. - sizeUnits: A comma-separated list of units used to display messages with human-readable file sizes. Defaults to
B, KB, MB(example:218 KB). You can useB,KB,MBinstead if you prefer without whitespaces (218KB).
- sbInit: Status message displayed initially if
- errorMessages: Errors displayed to the user, using the
errorCallbackoption, where#image_name#,#image_size#and#image_max_size#will replaced by their respective values, that can be used for customization or internationalization:- noFileGiven: The server did not receive any file from the user. Defaults to
You must select a file.. - typeNotAllowed: The user send a file type which doesn't match the
imageAcceptlist, or the server returned this error code. Defaults toThis image type is not allowed.. - fileTooLarge: The size of the image being imported is bigger than the
imageMaxSize, or if the server returned this error code. Defaults toImage #image_name# is too big (#image_size#).\nMaximum file size is #image_max_size#.. - importError: An unexpected error occurred when uploading the image. Defaults to
Something went wrong when uploading the image #image_name#..
- noFileGiven: The server did not receive any file from the user. Defaults to
- errorCallback: A callback function used to define how to display an error message. Defaults to
(errorMessage) => alert(errorMessage). - renderingConfig: Adjust settings for parsing the Markdown during previewing (not editing).
- codeSyntaxHighlighting: If set to
true, will highlight using highlight.js. Defaults tofalse. To use this feature you must include highlight.js on your page or pass in using thehljsoption. For example, include the script and the CSS files like:<script src="https://cdn.jsdelivr.net/highlight.js/latest/highlight.min.js"></script><link rel="stylesheet" href="https://cdn.jsdelivr.net/highlight.js/latest/styles/github.min.css"> - hljs: An injectible instance of highlight.js. If you don't want to rely on the global namespace (
window.hljs), you can provide an instance here. Defaults toundefined. - markedOptions: Set the internal Markdown renderer's options. Other
renderingConfigoptions will take precedence. - singleLineBreaks: If set to
false, disable parsing GitHub Flavored Markdown (GFM) single line breaks. Defaults totrue. - sanitizerFunction: Custom function for sanitizing the HTML output of Markdown renderer.
- codeSyntaxHighlighting: If set to
- shortcuts: Keyboard shortcuts associated with this instance. Defaults to the array of shortcuts.
- showIcons: An array of icon names to show. Can be used to show specific icons hidden by default without completely customizing the toolbar.
- spellChecker: If set to
false, disable the spell checker. Defaults totrue. Optionally pass a CodeMirrorSpellChecker-compliant function. - inputStyle:
textareaorcontenteditable. Defaults totextareafor desktop andcontenteditablefor mobile.contenteditableoption is necessary to enable nativeSpellcheck. - nativeSpellcheck: If set to
false, disable native spell checker. Defaults totrue. - sideBySideFullscreen: If set to
false, allows side-by-side editing without going into fullscreen. Defaults totrue. - status: If set to
false, hide the status bar. Defaults to the array of built-in status bar items.- Optionally, you can set an array of status bar items to include, and in what order. You can even define your own custom status bar items.
- styleSelectedText: If set to
false, remove theCodeMirror-selectedtextclass from selected lines. Defaults totrue. - syncSideBySidePreviewScroll: If set to
false, disable syncing scroll in side by side mode. Defaults totrue. - tabSize: If set, customize the tab size. Defaults to
2. - theme: Override the theme. Defaults to
easymde. - toolbar: If set to
false, hide the toolbar. Defaults to the array of icons. - toolbarTips: If set to
false, disable toolbar button tips. Defaults totrue. - direction:
rtlorltr. Changes text direction to support right-to-left languages. Defaults toltr.
Options example
Most options demonstrate the non-default behavior:
const editor = new EasyMDE({
autofocus: true,
autosave: {
enabled: true,
uniqueId: "MyUniqueID",
delay: 1000,
submit_delay: 5000,
timeFormat: {
locale: 'en-US',
format: {
year: 'numeric',
month: 'long',
day: '2-digit',
hour: '2-digit',
minute: '2-digit',
},
},
text: "Autosaved: "
},
blockStyles: {
bold: "__",
italic: "_",
},
unorderedListStyle: "-",
element: document.getElementById("MyID"),
forceSync: true,
hideIcons: ["guide", "heading"],
indentWithTabs: false,
initialValue: "Hello world!",
insertTexts: {
horizontalRule: ["", "\n\n-----\n\n"],
image: ["![](http://", ")"],
link: ["[", "](https://)"],
table: ["", "\n\n| Column 1 | Column 2 | Column 3 |\n| -------- | -------- | -------- |\n| Text | Text | Text |\n\n"],
},
lineWrapping: false,
minHeight: "500px",
parsingConfig: {
allowAtxHeaderWithoutSpace: true,
strikethrough: false,
underscoresBreakWords: true,
},
placeholder: "Type here...",
previewClass: "my-custom-styling",
previewClass: ["my-custom-styling", "more-custom-styling"],
previewRender: (plainText) => customMarkdownParser(plainText), // Returns HTML from a custom parser
previewRender: (plainText, preview) => { // Async method
setTimeout(() => {
preview.innerHTML = customMarkdownParser(plainText);
}, 250);
return "Loading...";
},
promptURLs: true,
promptTexts: {
image: "Custom prompt for URL:",
link: "Custom prompt for URL:",
},
renderingConfig: {
singleLineBreaks: false,
codeSyntaxHighlighting: true,
sanitizerFunction: (renderedHTML) => {
// Using DOMPurify and only allowing <b> tags
return DOMPurify.sanitize(renderedHTML, {ALLOWED_TAGS: ['b']})
},
},
shortcuts: {
drawTable: "Cmd-Alt-T"
},
showIcons: ["code", "table"],
spellChecker: false,
status: false,
status: ["autosave", "lines", "words", "cursor"], // Optional usage
status: ["autosave", "lines", "words", "cursor", {
className: "keystrokes",
defaultValue: (el) => {
el.setAttribute('data-keystrokes', 0);
},
onUpdate: (el) => {
const keystrokes = Number(el.getAttribute('data-keystrokes')) + 1;
el.innerHTML = `${keystrokes} Keystrokes`;
el.setAttribute('data-keystrokes', keystrokes);
},
}], // Another optional usage, with a custom status bar item that counts keystrokes
styleSelectedText: false,
sideBySideFullscreen: false,
syncSideBySidePreviewScroll: false,
tabSize: 4,
toolbar: false,
toolbarTips: false,
});
Toolbar icons
Below are the built-in toolbar icons (only some of which are enabled by default), which can be reorganized however you like. "Name" is the name of the icon, referenced in the JavaScript. "Action" is either a function or a URL to open. "Class" is the class given to the icon. "Tooltip" is the small tooltip that appears via the title="" attribute. Note that shortcut hints are added automatically and reflect the specified action if it has a key bind assigned to it (i.e. with the value of action set to bold and that of tooltip set to Bold, the final text the user will see would be "Bold (Ctrl-B)").
Additionally, you can add a separator between any icons by adding "|" to the toolbar array.
| Name | Action | Tooltip Class |
|---|---|---|
| bold | toggleBold | Bold fa fa-bold |
| italic | toggleItalic | Italic fa fa-italic |
| strikethrough | toggleStrikethrough | Strikethrough fa fa-strikethrough |
| heading | toggleHeadingSmaller | Heading fa fa-header |
| heading-smaller | toggleHeadingSmaller | Smaller Heading fa fa-header |
| heading-bigger | toggleHeadingBigger | Bigger Heading fa fa-lg fa-header |
| heading-1 | toggleHeading1 | Big Heading fa fa-header header-1 |
| heading-2 | toggleHeading2 | Medium Heading fa fa-header header-2 |
| heading-3 | toggleHeading3 | Small Heading fa fa-header header-3 |
| code | toggleCodeBlock | Code fa fa-code |
| quote | toggleBlockquote | Quote fa fa-quote-left |
| unordered-list | toggleUnorderedList | Generic List fa fa-list-ul |
| ordered-list | toggleOrderedList | Numbered List fa fa-list-ol |
| clean-block | cleanBlock | Clean block fa fa-eraser |
| link | drawLink | Create Link fa fa-link |
| image | drawImage | Insert Image fa fa-picture-o |
| table | drawTable | Insert Table fa fa-table |
| horizontal-rule | drawHorizontalRule | Insert Horizontal Line fa fa-minus |
| preview | togglePreview | Toggle Preview fa fa-eye no-disable |
| side-by-side | toggleSideBySide | Toggle Side by Side fa fa-columns no-disable no-mobile |
| fullscreen | toggleFullScreen | Toggle Fullscreen fa fa-arrows-alt no-disable no-mobile |
| guide | This link | Markdown Guide fa fa-question-circle |
| undo | undo | Undo fa fa-undo |
| redo | redo | Redo fa fa-redo |
Toolbar customization
Customize the toolbar using the toolbar option.
Only the order of existing buttons:
const easyMDE = new EasyMDE({
toolbar: ["bold", "italic", "heading", "|", "quote"]
});
All information and/or add your own icons
const easyMDE = new EasyMDE({
toolbar: [
{
name: "bold",
action: EasyMDE.toggleBold,
className: "fa fa-bold",
title: "Bold",
},
"italics", // shortcut to pre-made button
{
name: "custom",
action: (editor) => {
// Add your own code
},
className: "fa fa-star",
title: "Custom Button",
attributes: { // for custom attributes
id: "custom-id",
"data-value": "custom value" // HTML5 data-* attributes need to be enclosed in quotation marks ("") because of the dash (-) in its name.
}
},
"|" // Separator
// [, ...]
]
});
Put some buttons on dropdown menu
const easyMDE = new EasyMDE({
toolbar: [{
name: "heading",
action: EasyMDE.toggleHeadingSmaller,
className: "fa fa-header",
title: "Headers",
},
"|",
{
name: "others",
className: "fa fa-blind",
title: "others buttons",
children: [
{
name: "image",
action: EasyMDE.drawImage,
className: "fa fa-picture-o",
title: "Image",
},
{
name: "quote",
action: EasyMDE.toggleBlockquote,
className: "fa fa-percent",
title: "Quote",
},
{
name: "link",
action: EasyMDE.drawLink,
className: "fa fa-link",
title: "Link",
}
]
},
// [, ...]
]
});
Keyboard shortcuts
EasyMDE comes with an array of predefined keyboard shortcuts, but they can be altered with a configuration option. The list of default ones is as follows:
| Shortcut (Windows / Linux) | Shortcut (macOS) | Action |
|---|---|---|
| Ctrl-' | Cmd-' | "toggleBlockquote" |
| Ctrl-B | Cmd-B | "toggleBold" |
| Ctrl-E | Cmd-E | "cleanBlock" |
| Ctrl-H | Cmd-H | "toggleHeadingSmaller" |
| Ctrl-I | Cmd-I | "toggleItalic" |
| Ctrl-K | Cmd-K | "drawLink" |
| Ctrl-L | Cmd-L | "toggleUnorderedList" |
| Ctrl-P | Cmd-P | "togglePreview" |
| Ctrl-Alt-C | Cmd-Alt-C | "toggleCodeBlock" |
| Ctrl-Alt-I | Cmd-Alt-I | "drawImage" |
| Ctrl-Alt-L | Cmd-Alt-L | "toggleOrderedList" |
| Shift-Ctrl-H | Shift-Cmd-H | "toggleHeadingBigger" |
| F9 | F9 | "toggleSideBySide" |
| F11 | F11 | "toggleFullScreen" |
Here is how you can change a few, while leaving others untouched:
const editor = new EasyMDE({
shortcuts: {
"toggleOrderedList": "Ctrl-Alt-K", // alter the shortcut for toggleOrderedList
"toggleCodeBlock": null, // unbind Ctrl-Alt-C
"drawTable": "Cmd-Alt-T", // bind Cmd-Alt-T to drawTable action, which doesn't come with a default shortcut
}
});
Shortcuts are automatically converted between platforms. If you define a shortcut as "Cmd-B", on PC that shortcut will be changed to "Ctrl-B". Conversely, a shortcut defined as "Ctrl-B" will become "Cmd-B" for Mac users.
The list of actions that can be bound is the same as the list of built-in actions available for toolbar buttons.
Advanced use
Event handling
You can catch the following list of events: https://codemirror.net/doc/manual.html#events
const easyMDE = new EasyMDE();
easyMDE.codemirror.on("change", () => {
console.log(easyMDE.value());
});
Removing EasyMDE from text area
You can revert to the initial text area by calling the toTextArea method. Note that this clears up the autosave (if enabled) associated with it. The text area will retain any text from the destroyed EasyMDE instance.
const easyMDE = new EasyMDE();
// ...
easyMDE.toTextArea();
easyMDE = null;
If you need to remove registered event listeners (when the editor is not needed anymore), call easyMDE.cleanup().
Useful methods
The following self-explanatory methods may be of use while developing with EasyMDE.
const easyMDE = new EasyMDE();
easyMDE.isPreviewActive(); // returns boolean
easyMDE.isSideBySideActive(); // returns boolean
easyMDE.isFullscreenActive(); // returns boolean
easyMDE.clearAutosavedValue(); // no returned value
How it works
EasyMDE is a continuation of SimpleMDE.
SimpleMDE began as an improvement of lepture's Editor project, but has now taken on an identity of its own. It is bundled with CodeMirror and depends on Font Awesome.
CodeMirror is the backbone of the project and parses much of the Markdown syntax as it's being written. This allows us to add styles to the Markdown that's being written. Additionally, a toolbar and status bar have been added to the top and bottom, respectively. Previews are rendered by Marked using GitHub Flavored Markdown (GFM).
SimpleMDE fork
I originally made this fork to implement FontAwesome 5 compatibility into SimpleMDE. When that was done I submitted a pull request, which has not been accepted yet. This, and the project being inactive since May 2017, triggered me to make more changes and try to put new life into the project.
Changes include:
- FontAwesome 5 compatibility
- Guide button works when editor is in preview mode
- Links are now
https://by default - Small styling changes
- Support for Node 8 and beyond
- Lots of refactored code
- Links in preview will open in a new tab by default
- TypeScript support
My intention is to continue development on this project, improving it and keeping it alive.
Hacking EasyMDE
You may want to edit this library to adapt its behavior to your needs. This can be done in some quick steps:
- Follow the prerequisites and installation instructions in the contribution guide;
- Do your changes;
- Run
gulpcommand, which will generate files:dist/easymde.min.cssanddist/easymde.min.js; - Copy-paste those files to your code base, and you are done.
Contributing
Want to contribute to EasyMDE? Thank you! We have a contribution guide just for you!
Author: Ionaru
Source Code: https://github.com/Ionaru/easy-markdown-editor
License: MIT license
1659500100
Reform: Form Objects Decoupled From Models In Ruby
Reform
Form objects decoupled from your models.
Reform gives you a form object with validations and nested setup of models. It is completely framework-agnostic and doesn't care about your database.
Although reform can be used in any Ruby framework, it comes with Rails support, works with simple_form and other form gems, allows nesting forms to implement has_one and has_many relationships, can compose a form from multiple objects and gives you coercion.
Full Documentation
Reform is part of the Trailblazer framework. Full documentation is available on the project site.
Reform 2.2
Temporary note: Reform 2.2 does not automatically load Rails files anymore (e.g. ActiveModel::Validations). You need the reform-rails gem, see Installation.
Defining Forms
Forms are defined in separate classes. Often, these classes partially map to a model.
class AlbumForm < Reform::Form
property :title
validates :title, presence: true
end
Fields are declared using ::property. Validations work exactly as you know it from Rails or other frameworks. Note that validations no longer go into the model.
The API
Forms have a ridiculously simple API with only a handful of public methods.
#initializealways requires a model that the form represents.#validate(params)updates the form's fields with the input data (only the form, not the model) and then runs all validations. The return value is the boolean result of the validations.#errorsreturns validation messages in a classic ActiveModel style.#syncwrites form data back to the model. This will only use setter methods on the model(s).#save(optional) will call#saveon the model and nested models. Note that this implies a#synccall.#prepopulate!(optional) will run pre-population hooks to "fill out" your form before rendering.
In addition to the main API, forms expose accessors to the defined properties. This is used for rendering or manual operations.
Setup
In your controller or operation you create a form instance and pass in the models you want to work on.
class AlbumsController
def new
@form = AlbumForm.new(Album.new)
end
This will also work as an editing form with an existing album.
def edit
@form = AlbumForm.new(Album.find(1))
end
Reform will read property values from the model in setup. In our example, the AlbumForm will call album.title to populate the title field.
Rendering Forms
Your @form is now ready to be rendered, either do it yourself or use something like Rails' #form_for, simple_form or formtastic.
= form_for @form do |f|
= f.input :title
Nested forms and collections can be easily rendered with fields_for, etc. Note that you no longer pass the model to the form builder, but the Reform instance.
Optionally, you might want to use the #prepopulate! method to pre-populate fields and prepare the form for rendering.
Validation
After form submission, you need to validate the input.
class SongsController
def create
@form = SongForm.new(Song.new)
#=> params: {song: {title: "Rio", length: "366"}}
if @form.validate(params[:song])
The #validate method first updates the values of the form - the underlying model is still treated as immutuable and remains unchanged. It then runs all validations you provided in the form.
It's the only entry point for updating the form. This is per design, as separating writing and validation doesn't make sense for a form.
This allows rendering the form after validate with the data that has been submitted. However, don't get confused, the model's values are still the old, original values and are only changed after a #save or #sync operation.
Syncing Back
After validation, you have two choices: either call #save and let Reform sort out the rest. Or call #sync, which will write all the properties back to the model. In a nested form, this works recursively, of course.
It's then up to you what to do with the updated models - they're still unsaved.
Saving Forms
The easiest way to save the data is to call #save on the form.
if @form.validate(params[:song])
@form.save #=> populates album with incoming data
# by calling @form.album.title=.
else
# handle validation errors.
end
This will sync the data to the model and then call album.save.
Sometimes, you need to do saving manually.
Default values
Reform allows default values to be provided for properties.
class AlbumForm < Reform::Form
property :price_in_cents, default: 9_95
end
Saving Forms Manually
Calling #save with a block will provide a nested hash of the form's properties and values. This does not call #save on the models and allows you to implement the saving yourself.
The block parameter is a nested hash of the form input.
@form.save do |hash|
hash #=> {title: "Greatest Hits"}
Album.create(hash)
end
You can always access the form's model. This is helpful when you were using populators to set up objects when validating.
@form.save do |hash|
album = @form.model
album.update_attributes(hash[:album])
end
Nesting
Reform provides support for nested objects. Let's say the Album model keeps some associations.
class Album < ActiveRecord::Base
has_one :artist
has_many :songs
end
The implementation details do not really matter here, as long as your album exposes readers and writes like Album#artist and Album#songs, this allows you to define nested forms.
class AlbumForm < Reform::Form
property :title
validates :title, presence: true
property :artist do
property :full_name
validates :full_name, presence: true
end
collection :songs do
property :name
end
end
You can also reuse an existing form from elsewhere using :form.
property :artist, form: ArtistForm
Nested Setup
Reform will wrap defined nested objects in their own forms. This happens automatically when instantiating the form.
album.songs #=> [<Song name:"Run To The Hills">]
form = AlbumForm.new(album)
form.songs[0] #=> <SongForm model: <Song name:"Run To The Hills">>
form.songs[0].name #=> "Run To The Hills"
Nested Rendering
When rendering a nested form you can use the form's readers to access the nested forms.
= text_field :title, @form.title
= text_field "artist[name]", @form.artist.name
Or use something like #fields_for in a Rails environment.
= form_for @form do |f|
= f.text_field :title
= f.fields_for :artist do |a|
= a.text_field :name
Nested Processing
validate will assign values to the nested forms. sync and save work analogue to the non-nested form, just in a recursive way.
The block form of #save would give you the following data.
@form.save do |nested|
nested #=> {title: "Greatest Hits",
# artist: {name: "Duran Duran"},
# songs: [{title: "Hungry Like The Wolf"},
# {title: "Last Chance On The Stairways"}]
# }
end
The manual saving with block is not encouraged. You should rather check the Disposable docs to find out how to implement your manual tweak with the official API.
Populating Forms
Very often, you need to give Reform some information how to create or find nested objects when validateing. This directive is called populator and documented here.
Installation
Add this line to your Gemfile:
gem "reform"
Reform works fine with Rails 3.1-5.0. However, inheritance of validations with ActiveModel::Validations is broken in Rails 3.2 and 4.0.
Since Reform 2.2, you have to add the reform-rails gem to your Gemfile to automatically load ActiveModel/Rails files.
gem "reform-rails"
Since Reform 2.0 you need to specify which validation backend you want to use (unless you're in a Rails environment where ActiveModel will be used).
To use ActiveModel (not recommended because very out-dated).
require "reform/form/active_model/validations"
Reform::Form.class_eval do
include Reform::Form::ActiveModel::Validations
end
To use dry-validation (recommended).
require "reform/form/dry"
Reform::Form.class_eval do
feature Reform::Form::Dry
end
Put this in an initializer or on top of your script.
Compositions
Reform allows to map multiple models to one form. The complete documentation is here, however, this is how it works.
class AlbumForm < Reform::Form
include Composition
property :id, on: :album
property :title, on: :album
property :songs, on: :cd
property :cd_id, on: :cd, from: :id
end
When initializing a composition, you have to pass a hash that contains the composees.
AlbumForm.new(album: album, cd: CD.find(1))
More
Reform comes many more optional features, like hash fields, coercion, virtual fields, and so on. Check the full documentation here.
Reform is part of the Trailblazer project. Please buy my book to support the development and learn everything about Reform - there's two chapters dedicated to Reform!
Security And Strong_parameters
By explicitly defining the form layout using ::property there is no more need for protecting from unwanted input. strong_parameter or attr_accessible become obsolete. Reform will simply ignore undefined incoming parameters.
This is not Reform 1.x!
Temporary note: This is the README and API for Reform 2. On the public API, only a few tiny things have changed. Here are the Reform 1.2 docs.
Anyway, please upgrade and report problems and do not simply assume that we will magically find out what needs to get fixed. When in trouble, join us on Gitter.
Full documentation for Reform is available online, or support us and grab the Trailblazer book. There is an Upgrading Guide to help you migrate through versions.
Attributions!!!
Great thanks to Blake Education for giving us the freedom and time to develop this project in 2013 while working on their project.
Author: trailblazer
Source code: https://github.com/trailblazer/reform
License: MIT license
1620466520
Your Data Architecture: Simple Best Practices for Your Data Strategy
If you accumulate data on which you base your decision-making as an organization, you should probably think about your data architecture and possible best practices.
If you accumulate data on which you base your decision-making as an organization, you most probably need to think about your data architecture and consider possible best practices. Gaining a competitive edge, remaining customer-centric to the greatest extent possible, and streamlining processes to get on-the-button outcomes can all be traced back to an organization’s capacity to build a future-ready data architecture.
In what follows, we offer a short overview of the overarching capabilities of data architecture. These include user-centricity, elasticity, robustness, and the capacity to ensure the seamless flow of data at all times. Added to these are automation enablement, plus security and data governance considerations. These points from our checklist for what we perceive to be an anticipatory analytics ecosystem.
#big data #data science #big data analytics #data analysis #data architecture #data transformation #data platform #data strategy #cloud data platform #data acquisition
1595396220
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:
- 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.
- 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:
- 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.
- 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.
- 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
1601381326
Public ASX100 APIs: The Essential List
We’ve conducted some initial research into the public APIs of the ASX100 because we regularly have conversations about what others are doing with their APIs and what best practices look like. Being able to point to good local examples and explain what is happening in Australia is a key part of this conversation.
Method
The method used for this initial research was to obtain a list of the ASX100 (as of 18 September 2020). Then work through each company looking at the following:
- Whether the company had a public API: this was found by googling “[company name] API” and “[company name] API developer” and “[company name] developer portal”. Sometimes the company’s website was navigated or searched.
- Some data points about the API were noted, such as the URL of the portal/documentation and the method they used to publish the API (portal, documentation, web page).
- Observations were recorded that piqued the interest of the researchers (you will find these below).
- Other notes were made to support future research.
- You will find a summary of the data in the infographic below.
Data
With regards to how the APIs are shared:
- Documentation is where just the Swagger/OpenAPI docs are hosted somewhere. e.g. https://api.linkgroup.com/member/docs/index
- Portal is where an interactive portal has been developed. e.g. https://dev.telstra.com/
- The web page is where the company has a single page that isn’t interactive explaining their Public APIs. e.g. https://www.bendigoadelaide.com.au/banking-products-api.asp
#api #api-development #api-analytics #apis #api-integration #api-testing #api-security #api-gateway