mobiledoc-kit

Mobiledoc Kit

Mobiledoc Kit (warning: beta) is a library for building WYSIWYG editors supporting rich content via cards.

Try a demo at bustlelabs.github.io/mobiledoc-kit/demo.

• Posts are serialized to a JSON format called Mobiledoc instead of to HTML. Mobiledoc can be rendered for the web, mobile web, or in theory on any platform. Mobiledoc is portable and fast.
• The editor makes limited use of Content Editable, the siren-song of doomed web editor technologies.
• Mobiledoc is designed for rich content. We call rich sections of an article "cards" and rich inline elements "atoms" and implementing a new one doesn't require an understanding of Mobiledoc editor internals. Adding a new atom or card takes an afternoon, not several days. To learn more, see the docs for Atoms, Cards and Mobiledoc Renderers

To learn more about the ideas behind Mobiledoc and the editor (note that the editor used to be named Content-Kit), see these blog posts:

• The Content-Kit announcement post.
• Building the Content-Kit Editor on Content Editable
• Content-Kit: Programmatic Editing

The Mobiledoc kit saves posts in Mobiledoc format.

Usage

The Mobiledoc.Editor class is invoked with an element to render into and optionally a Mobiledoc to load. For example:

var simpleMobiledoc = {
  version: "0.1",
  sections: [[], [
    [1, "p", [
      [[], 0, "Welcome to Mobiledoc"]
    ]]
  ]]
};
var element = document.querySelector('#editor');
var options = { mobiledoc: simpleMobiledoc };
var editor = new Mobiledoc.Editor(options);
editor.render(element);

options is an object which may include the following properties:

• placeholder - [string] default text to show before a user starts typing.
• spellcheck - [boolean] whether to enable spellcheck. Defaults to true.
• autofocus - [boolean] When true, focuses on the editor when it is rendered.
• cards - [array] The list of cards that the editor may render
• cardOptions - [object] Options passed to cards and atoms
• unknownCardHandler - [function] This will be invoked by the editor-renderer whenever it encounters an unknown card

Editor API

• editor.serialize() - serialize the current post for persistence. Returns Mobiledoc.
• editor.destroy() - teardown the editor event listeners, free memory etc.
• editor.disableEditing() - stop the user from being able to edit the current post with their cursor. Programmatic edits are still allowed.
• editor.enableEditing() - allow the user to make direct edits directly to a post's text.
• editor.editCard(cardSection) - change the card to its edit mode (will change immediately if the card is already rendered, or will ensure that when the card does get rendered it will be rendered in the "edit" state initially)
• editor.displayCard(cardSection) - same as editCard except in display mode.

Editor Lifecycle Hooks

API consumers may want to react to given interaction by the user (or by a programmatic edit of the post). Lifecyle hooks provide notification of change and opportunity to edit the post where appropriate.

Register a lifecycle hook by calling the hook name on the editor with a callback function. For example:

editor.didUpdatePost(postEditor => {
  let { offsets } = editor.cursor,
      cursorSection;

  if (offset.headSection.text === 'add-section-when-i-type-this') {
    let section = editor.builder.createMarkupSection('p');
    postEditor.insertSectionBefore(section, cursorSection.next);
    cursorSection = section;
  }

  postEditor.scheduleRerender();
  postEditor.schedule(() => {
    if (cursorSection) {
      editor.moveToSection(cursorSection, 0);
    }
  });
});

The available lifecycle hooks are:

• editor.didUpdatePost(postEditor => {}) - An opportunity to use the postEditor and possibly change the post before rendering begins.
• editor.willRender() - After all post mutation has finished, but before the DOM is updated.
• editor.didRender() - After the DOM has been updated to match the edited post.
• editor.cursorDidChange() - When the cursor (or selection) changes as a result of arrow-key movement or clicking in the document.

Programmatic Post Editing

A major goal of the Mobiledoc kit is to allow complete customization of user interfaces using the editing surface. The programmatic editing API allows the creation of completely custom interfaces for buttons, hot-keys, and other interactions.

To change the post in code, use the editor.run API. For example, the following usage would mark currently selected text as "strong":

editor.run(postEditor => {
  postEditor.toggleMarkup('strong');
});

It is important that you make changes to posts, sections, and markers through the run and postEditor API. This API allows the Mobiledoc editor to conserve and better understand changes being made to the post.

editor.run(postEditor => {
  const mention = postEditor.builder.createAtom("mention", "John Doe", { id: 42 });
  // insert at current cursor position:
  // or should the user have to grab the current position from the editor first?
  postEditor.insertMarkers(editor.range.head, [mention]);
});

For more details on the API of postEditor, see the API documentation.

For more details on the API for the builder, required to create new sections atoms, and markers, see the builder API.

Configuring hot keys

The Mobiledoc editor allows the configuration of hot keys and text expansions. For instance, the hot-key command-B to make selected text bold, is registered internally as:

const boldKeyCommand = {
  str: 'META+B',
  run(editor) {
    editor.run(postEditor => postEditor.toggleMarkup('strong'));
  }
};
editor.registerKeyCommand(boldKeyCommand);

All key commands must have str and run properties as shown above.

str describes the key combination to use and may be a single key, or modifier(s) and a key separated by +, e.g.: META+K (cmd-K), META+SHIFT+K (cmd-shift-K)

Modifiers can be any of CTRL, META, SHIFT, or ALT.

The key can be any of the alphanumeric characters on the keyboard, or one of the following special keys:

BACKSPACE, TAB, ENTER, ESC, SPACE, PAGEUP, PAGEDOWN, END, HOME, LEFT, UP, RIGHT, DOWN, INS, DEL

Overriding built-in keys

You can override built-in behavior by simply registering a hot key with the same name. For example, to submit a form instead of entering a new line when enter is pressed you could do the following:

const enterKeyCommand = {
  str: 'enter',
  run(editor) {
    // submit the form
  }
};
editor.registerKeyCommand(enterKeyCommand);

To fall-back to the default behavior, return false from run.

Configuring text expansions

Text expansions can also be registered with the editor. These are functions that are run when a text string is entered and then a trigger character is entered. For example, the text "*" followed by a space character triggers a function that turns the current section into a list item. To register a text expansion call editor.registerExpansion with an object that has text, trigger and run properties, e.g.:

const expansion = {
  trigger: ' ',
  text: 'X',
  run(editor) {
    // use the editor to programmatically change the post
  }
};

DOM Parsing hooks

A developer can override the default parsing behavior for leaf DOM nodes in pasted HTML.

For example, when an img tag is pasted it may be appropriate to fetch that image, upload it to an authoritative source, and create a specific kind of image card with the new URL in its payload.

A demonstration of this:

function imageToCardParser(node, builder, {addSection, addMarkerable, nodeFinished}) {
  if (node.nodeType !== 1 || node.tagName !== 'IMG') {
    return;
  }
  var payload = { src: node.src };
  var cardSection = builder.createCardSection('my-image', payload);
  addSection(cardSection);
  nodeFinished();
}
var options = {
  parserPlugins: [imageToCardParser]
};
var editor = new Mobiledoc.Editor(options);
var element = document.querySelector('#editor');
editor.render(element);

Parser hooks are called with two arguments:

• node - The node of DOM being parsed. This may be a text node or an element.
• builder - The abstract model builder.
• env - An object containing three callbacks to modify the abstract
  • addSection - Close the current section and add a new one
  • addMarkerable - Add a markerable (marker or atom) to the current section
  • nodeFinished - Bypass all remaining parse steps for this node

Note that you must call nodeFinished to stop a DOM node from being parsed by the next plugin or the default parser.

Contributing

Fork the repo, write a test, make a change, open a PR.

Tests

Install npm and bower:

• Node.js is required
• npm install -g npm && npm install -g bower
• broccoli, via npm install -g broccoli-cli
• bower install
• npm install

Run tests via the built-in broccoli server:

• broccoli serve
• open http://localhost:4200/tests

Or run headless tests via testem:

• npm test

Demo

There is a demo app that uses the Mobiledoc kit via the ember-mobiledoc-editor in demo/. To run the demo:

• cd demo/ && npm install && bower install
• ember serve (shut down your broccoli server if it is already running on port 4200)
• visit http://localhost:4200/

Releasing

• npm version patch or minor or major
• npm run update-changelog
• npm run build
• git push <origin> --follow-tags
• npm publish

Deploy the demo

The demo website is hosted at github pages. To publish a new version:

• npm run build-website - This builds the website into website/ and commits it
• npm run deploy-website - Pushes the website/ subtree to the gh-pages branch of your origin at github

Visit bustlelabs.github.io/mobiledoc-kit/demo.

Development of Mobiledoc and the supporting libraries was generously funded by Bustle Labs. Bustle Labs is the tech team behind the editorial staff at Bustle, a fantastic and successful feminist and women’s interest site based in NYC.