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 // Cached references to DOM elements
dom = {}, 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 supported by the browser, see #checkCapabilities()
features = {}, features = {},
@ -434,7 +440,7 @@
// Hide the address bar in mobile browsers // Hide the address bar in mobile browsers
hideAddressBar(); hideAddressBar();
// Loads the dependencies and continues to #start() once done // Loads dependencies and continues to #start() once done
load(); load();
} }
@ -489,37 +495,22 @@
function load() { function load() {
var scripts = [], var scripts = [],
scriptsAsync = [], scriptsToLoad = 0;
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];
config.dependencies.forEach( function( s ) {
// Load if there's no condition or the condition is truthy // Load if there's no condition or the condition is truthy
if( !s.condition || s.condition() ) { if( !s.condition || s.condition() ) {
if( s.async ) { if( s.async ) {
scriptsAsync.push( s ); asyncDependencies.push( s );
} }
else { else {
scripts.push( s ); scripts.push( s );
} }
} }
} } );
if( scripts.length ) { if( scripts.length ) {
scriptsToPreload = scripts.length; scriptsToLoad = scripts.length;
// Load synchronous scripts // Load synchronous scripts
scripts.forEach( function( s ) { scripts.forEach( function( s ) {
@ -527,21 +518,66 @@
if( typeof s.callback === 'function' ) s.callback(); if( typeof s.callback === 'function' ) s.callback();
if( --scriptsToPreload === 0 ) { if( --scriptsToLoad === 0 ) {
loadPlugins();
afterSynchronousScriptsLoaded();
} }
} ); } );
} ); } );
} }
else { 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. * 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 * Add a custom key binding with optional description to
* be added to the help screen. * be added to the help screen.
@ -5845,12 +5890,13 @@
} }
}, },
// Adds a custom key binding // Adds/remvoes a custom key binding
addKeyBinding: addKeyBinding, addKeyBinding: addKeyBinding,
// Removes a custom key binding
removeKeyBinding: removeKeyBinding, removeKeyBinding: removeKeyBinding,
// Called by plugins to register/unregister themselves
registerPlugin: registerPlugin,
// Programatically triggers a keyboard event // Programatically triggers a keyboard event
triggerKey: function( keyCode ) { triggerKey: function( keyCode ) {
onDocumentKeyDown( { keyCode: keyCode } ); onDocumentKeyDown( { keyCode: keyCode } );

View File

@ -7,13 +7,11 @@
if (typeof define === 'function' && define.amd) { if (typeof define === 'function' && define.amd) {
root.marked = require( './marked' ); root.marked = require( './marked' );
root.RevealMarkdown = factory( root.marked ); root.RevealMarkdown = factory( root.marked );
root.RevealMarkdown.initialize();
} else if( typeof exports === 'object' ) { } else if( typeof exports === 'object' ) {
module.exports = factory( require( './marked' ) ); module.exports = factory( require( './marked' ) );
} else { } else {
// Browser globals (root is window) // Browser globals (root is window)
root.RevealMarkdown = factory( root.marked ); root.RevealMarkdown = factory( root.marked );
root.RevealMarkdown.initialize();
} }
}( this, function( marked ) { }( this, function( marked ) {
@ -24,6 +22,10 @@
var SCRIPT_END_PLACEHOLDER = '__SCRIPT_END__'; var SCRIPT_END_PLACEHOLDER = '__SCRIPT_END__';
var markdownFilesToLoad = 0;
var loadCallback;
/** /**
* Retrieves the markdown contents of a slide section * Retrieves the markdown contents of a slide section
@ -199,15 +201,37 @@
*/ */
function processSlides() { function processSlides() {
var sections = document.querySelectorAll( '[data-markdown]'), [].slice.call( document.querySelectorAll( '[data-markdown]') ).forEach( function( section, i ) {
section;
for( var i = 0, len = sections.length; i < len; i++ ) {
section = sections[i];
if( section.getAttribute( 'data-markdown' ).length ) { if( section.getAttribute( 'data-markdown' ).length ) {
loadExternalMarkdown( section );
}
else if( section.getAttribute( 'data-separator' ) || section.getAttribute( 'data-separator-vertical' ) || section.getAttribute( 'data-separator-notes' ) ) {
section.outerHTML = slidify( getMarkdownFromSlide( section ), {
separator: section.getAttribute( 'data-separator' ),
verticalSeparator: section.getAttribute( 'data-separator-vertical' ),
notesSeparator: section.getAttribute( 'data-separator-notes' ),
attributes: getForwardedAttributes( section )
});
}
else {
section.innerHTML = createMarkdownSlide( getMarkdownFromSlide( section ) );
}
});
checkIfLoaded();
}
function loadExternalMarkdown( section ) {
markdownFilesToLoad += 1;
var xhr = new XMLHttpRequest(), var xhr = new XMLHttpRequest(),
url = section.getAttribute( 'data-markdown' ); url = section.getAttribute( 'data-markdown' );
@ -218,7 +242,7 @@
xhr.overrideMimeType( 'text/html; charset=' + datacharset ); xhr.overrideMimeType( 'text/html; charset=' + datacharset );
} }
xhr.onreadystatechange = function() { xhr.onreadystatechange = function( section, xhr ) {
if( xhr.readyState === 4 ) { if( xhr.readyState === 4 ) {
// file protocol yields status code 0 (useful for local debug, mobile applications etc.) // file protocol yields status code 0 (useful for local debug, mobile applications etc.)
if ( ( xhr.status >= 200 && xhr.status < 300 ) || xhr.status === 0 ) { if ( ( xhr.status >= 200 && xhr.status < 300 ) || xhr.status === 0 ) {
@ -240,10 +264,16 @@
'</section>'; '</section>';
} }
}
};
xhr.open( 'GET', url, false ); convertSlides();
markdownFilesToLoad -= 1;
checkIfLoaded();
}
}.bind( this, section, xhr );
xhr.open( 'GET', url, true );
try { try {
xhr.send(); xhr.send();
@ -252,22 +282,6 @@
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 ); 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 );
} }
}
else if( section.getAttribute( 'data-separator' ) || section.getAttribute( 'data-separator-vertical' ) || section.getAttribute( 'data-separator-notes' ) ) {
section.outerHTML = slidify( getMarkdownFromSlide( section ), {
separator: section.getAttribute( 'data-separator' ),
verticalSeparator: section.getAttribute( 'data-separator-vertical' ),
notesSeparator: section.getAttribute( 'data-separator-notes' ),
attributes: getForwardedAttributes( section )
});
}
else {
section.innerHTML = createMarkdownSlide( getMarkdownFromSlide( section ) );
}
}
} }
/** /**
@ -342,14 +356,9 @@
*/ */
function convertSlides() { 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];
// Only parse the same slide once
if( !section.getAttribute( 'data-markdown-parsed' ) ) {
section.setAttribute( 'data-markdown-parsed', true ) section.setAttribute( 'data-markdown-parsed', true )
@ -370,16 +379,33 @@
section.appendChild( notes ); section.appendChild( notes );
} }
} );
} }
function checkIfLoaded() {
if( markdownFilesToLoad === 0 ) {
if( loadCallback ) {
loadCallback();
loadCallback = null;
}
} }
} }
// API // 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' ) { if( typeof marked === 'undefined' ) {
throw 'The reveal.js Markdown plugin requires marked to be loaded'; 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; var options = Reveal.getConfig().markdown;
if( options ) { if( options ) {
marked.setOptions( options ); marked.setOptions( options );
} }
loadCallback = callback;
processSlides(); processSlides();
convertSlides(); convertSlides();
}, },
// TODO: Do these belong in the API? // 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;
})); }));