async loading of external markdown, add Reveal.registerPlugin()

This commit is contained in:
Hakim El Hattab 2019-03-01 21:28:52 +01:00
parent 213023760a
commit 4862de26eb
2 changed files with 188 additions and 107 deletions

View File

@ -319,6 +319,12 @@
// Cached references to DOM elements
dom = {},
// A list of registered reveal.js plugins
plugins = {},
// List of asynchronously loaded reveal.js dependencies
asyncDependencies = [],
// Features supported by the browser, see #checkCapabilities()
features = {},
@ -434,7 +440,7 @@
// Hide the address bar in mobile browsers
hideAddressBar();
// Loads the dependencies and continues to #start() once done
// Loads dependencies and continues to #start() once done
load();
}
@ -489,37 +495,22 @@
function load() {
var scripts = [],
scriptsAsync = [],
scriptsToPreload = 0;
// Called once synchronous scripts finish loading
function afterSynchronousScriptsLoaded() {
// Load asynchronous scripts
if( scriptsAsync.length ) {
scriptsAsync.forEach( function( s ) {
loadScript( s.src, s.callback );
} );
}
start();
}
for( var i = 0, len = config.dependencies.length; i < len; i++ ) {
var s = config.dependencies[i];
scriptsToLoad = 0;
config.dependencies.forEach( function( s ) {
// Load if there's no condition or the condition is truthy
if( !s.condition || s.condition() ) {
if( s.async ) {
scriptsAsync.push( s );
asyncDependencies.push( s );
}
else {
scripts.push( s );
}
}
}
} );
if( scripts.length ) {
scriptsToPreload = scripts.length;
scriptsToLoad = scripts.length;
// Load synchronous scripts
scripts.forEach( function( s ) {
@ -527,21 +518,66 @@
if( typeof s.callback === 'function' ) s.callback();
if( --scriptsToPreload === 0 ) {
afterSynchronousScriptsLoaded();
if( --scriptsToLoad === 0 ) {
loadPlugins();
}
} );
} );
}
else {
afterSynchronousScriptsLoaded();
loadPlugins();
}
}
/**
* Loads all plugins that require preloading.
*/
function loadPlugins() {
var pluginsToLoad = Object.keys( plugins ).length;
for( var i in plugins ) {
var plugin = plugins[i];
// If the plugin has an 'init' method, initialize and
// wait for the callback
if( typeof plugin.init === 'function' ) {
plugin.init( function() {
if( --pluginsToLoad === 0 ) {
loadAsyncDependencies();
}
} );
}
else {
pluginsToLoad -= 1;
}
}
if( pluginsToLoad === 0 ) {
loadAsyncDependencies();
}
}
/**
* Loads all async reveal.js dependencies.
*/
function loadAsyncDependencies() {
if( asyncDependencies.length ) {
asyncDependencies.forEach( function( s ) {
loadScript( s.src, s.callback );
} );
}
start();
}
/**
* Loads a JavaScript file from the given URL and executes it.
*
@ -1512,6 +1548,15 @@
}
/**
* Registers a new plugin with this reveal.js instance.
*/
function registerPlugin( id, plugin ) {
plugins[id] = plugin;
}
/**
* Add a custom key binding with optional description to
* be added to the help screen.
@ -5845,12 +5890,13 @@
}
},
// Adds a custom key binding
// Adds/remvoes a custom key binding
addKeyBinding: addKeyBinding,
// Removes a custom key binding
removeKeyBinding: removeKeyBinding,
// Called by plugins to register/unregister themselves
registerPlugin: registerPlugin,
// Programatically triggers a keyboard event
triggerKey: function( keyCode ) {
onDocumentKeyDown( { keyCode: keyCode } );

View File

@ -7,13 +7,11 @@
if (typeof define === 'function' && define.amd) {
root.marked = require( './marked' );
root.RevealMarkdown = factory( root.marked );
root.RevealMarkdown.initialize();
} else if( typeof exports === 'object' ) {
module.exports = factory( require( './marked' ) );
} else {
// Browser globals (root is window)
root.RevealMarkdown = factory( root.marked );
root.RevealMarkdown.initialize();
}
}( this, function( marked ) {
@ -24,6 +22,10 @@
var SCRIPT_END_PLACEHOLDER = '__SCRIPT_END__';
var markdownFilesToLoad = 0;
var loadCallback;
/**
* Retrieves the markdown contents of a slide section
@ -199,58 +201,11 @@
*/
function processSlides() {
var sections = document.querySelectorAll( '[data-markdown]'),
section;
for( var i = 0, len = sections.length; i < len; i++ ) {
section = sections[i];
[].slice.call( document.querySelectorAll( '[data-markdown]') ).forEach( function( section, i ) {
if( section.getAttribute( 'data-markdown' ).length ) {
var xhr = new XMLHttpRequest(),
url = section.getAttribute( 'data-markdown' );
datacharset = section.getAttribute( 'data-charset' );
// see https://developer.mozilla.org/en-US/docs/Web/API/element.getAttribute#Notes
if( datacharset != null && datacharset != '' ) {
xhr.overrideMimeType( 'text/html; charset=' + datacharset );
}
xhr.onreadystatechange = function() {
if( xhr.readyState === 4 ) {
// file protocol yields status code 0 (useful for local debug, mobile applications etc.)
if ( ( xhr.status >= 200 && xhr.status < 300 ) || xhr.status === 0 ) {
section.outerHTML = slidify( xhr.responseText, {
separator: section.getAttribute( 'data-separator' ),
verticalSeparator: section.getAttribute( 'data-separator-vertical' ),
notesSeparator: section.getAttribute( 'data-separator-notes' ),
attributes: getForwardedAttributes( section )
});
}
else {
section.outerHTML = '<section data-state="alert">' +
'ERROR: The attempt to fetch ' + url + ' failed with HTTP status ' + xhr.status + '.' +
'Check your browser\'s JavaScript console for more details.' +
'<p>Remember that you need to serve the presentation HTML from a HTTP server.</p>' +
'</section>';
}
}
};
xhr.open( 'GET', url, false );
try {
xhr.send();
}
catch ( e ) {
alert( 'Failed to get the Markdown file ' + url + '. Make sure that the presentation and the file are served by a HTTP server and the file can be found there. ' + e );
}
loadExternalMarkdown( section );
}
else if( section.getAttribute( 'data-separator' ) || section.getAttribute( 'data-separator-vertical' ) || section.getAttribute( 'data-separator-notes' ) ) {
@ -266,6 +221,65 @@
else {
section.innerHTML = createMarkdownSlide( getMarkdownFromSlide( section ) );
}
});
checkIfLoaded();
}
function loadExternalMarkdown( section ) {
markdownFilesToLoad += 1;
var xhr = new XMLHttpRequest(),
url = section.getAttribute( 'data-markdown' );
datacharset = section.getAttribute( 'data-charset' );
// see https://developer.mozilla.org/en-US/docs/Web/API/element.getAttribute#Notes
if( datacharset != null && datacharset != '' ) {
xhr.overrideMimeType( 'text/html; charset=' + datacharset );
}
xhr.onreadystatechange = function( section, xhr ) {
if( xhr.readyState === 4 ) {
// file protocol yields status code 0 (useful for local debug, mobile applications etc.)
if ( ( xhr.status >= 200 && xhr.status < 300 ) || xhr.status === 0 ) {
section.outerHTML = slidify( xhr.responseText, {
separator: section.getAttribute( 'data-separator' ),
verticalSeparator: section.getAttribute( 'data-separator-vertical' ),
notesSeparator: section.getAttribute( 'data-separator-notes' ),
attributes: getForwardedAttributes( section )
});
}
else {
section.outerHTML = '<section data-state="alert">' +
'ERROR: The attempt to fetch ' + url + ' failed with HTTP status ' + xhr.status + '.' +
'Check your browser\'s JavaScript console for more details.' +
'<p>Remember that you need to serve the presentation HTML from a HTTP server.</p>' +
'</section>';
}
convertSlides();
markdownFilesToLoad -= 1;
checkIfLoaded();
}
}.bind( this, section, xhr );
xhr.open( 'GET', url, true );
try {
xhr.send();
}
catch ( e ) {
alert( 'Failed to get the Markdown file ' + url + '. Make sure that the presentation and the file are served by a HTTP server and the file can be found there. ' + e );
}
}
@ -342,44 +356,56 @@
*/
function convertSlides() {
var sections = document.querySelectorAll( '[data-markdown]');
var sections = document.querySelectorAll( '[data-markdown]:not([data-markdown-parsed])');
for( var i = 0, len = sections.length; i < len; i++ ) {
[].slice.call( sections ).forEach( function( section ) {
var section = sections[i];
section.setAttribute( 'data-markdown-parsed', true )
// Only parse the same slide once
if( !section.getAttribute( 'data-markdown-parsed' ) ) {
var notes = section.querySelector( 'aside.notes' );
var markdown = getMarkdownFromSlide( section );
section.setAttribute( 'data-markdown-parsed', true )
var notes = section.querySelector( 'aside.notes' );
var markdown = getMarkdownFromSlide( section );
section.innerHTML = marked( markdown );
addAttributes( section, section, null, section.getAttribute( 'data-element-attributes' ) ||
section.parentNode.getAttribute( 'data-element-attributes' ) ||
DEFAULT_ELEMENT_ATTRIBUTES_SEPARATOR,
section.getAttribute( 'data-attributes' ) ||
section.parentNode.getAttribute( 'data-attributes' ) ||
DEFAULT_SLIDE_ATTRIBUTES_SEPARATOR);
// If there were notes, we need to re-add them after
// having overwritten the section's HTML
if( notes ) {
section.appendChild( notes );
}
section.innerHTML = marked( markdown );
addAttributes( section, section, null, section.getAttribute( 'data-element-attributes' ) ||
section.parentNode.getAttribute( 'data-element-attributes' ) ||
DEFAULT_ELEMENT_ATTRIBUTES_SEPARATOR,
section.getAttribute( 'data-attributes' ) ||
section.parentNode.getAttribute( 'data-attributes' ) ||
DEFAULT_SLIDE_ATTRIBUTES_SEPARATOR);
// If there were notes, we need to re-add them after
// having overwritten the section's HTML
if( notes ) {
section.appendChild( notes );
}
} );
}
function checkIfLoaded() {
if( markdownFilesToLoad === 0 ) {
if( loadCallback ) {
loadCallback();
loadCallback = null;
}
}
}
// API
return {
var RevealMarkdown = {
/**
* Starts processing and converting Markdown within the
* current reveal.js deck.
*
* @param {function} callback function to invoke once
* we've finished loading and parsing Markdown
*/
init: function( callback ) {
initialize: function() {
if( typeof marked === 'undefined' ) {
throw 'The reveal.js Markdown plugin requires marked to be loaded';
}
@ -392,14 +418,17 @@
});
}
// marked can be configured via reveal.js config options
var options = Reveal.getConfig().markdown;
if ( options ) {
if( options ) {
marked.setOptions( options );
}
loadCallback = callback;
processSlides();
convertSlides();
},
// TODO: Do these belong in the API?
@ -409,4 +438,10 @@
};
// Register our plugin so that reveal.js will call our
// plugin 'init' method as part of the initialization
Reveal.registerPlugin( 'markdown', RevealMarkdown );
return RevealMarkdown;
}));