refactor: move xmodule folder to root

- Moving xmodule folder to root as we're dissolving sub-projects of common folder in edx-platform - More info: https://openedx.atlassian.net/browse/BOM-2579 - -e common/lib/xmodule has been removed from the requirements as xmodule has itself become the part of edx-platform and not being installed through requirements - The test files common/lib/xmodule/test_files/ have been removed as they are not being used anymore
2022-05-19 21:40:48 +05:00
parent 26c8ec5c2a
commit a91df0c40f
487 changed files with 216 additions and 339 deletions
--- a/xmodule/js/src/javascript_loader.js
+++ b/xmodule/js/src/javascript_loader.js
@@ -0,0 +1,89 @@
+(function() {
+    'use strict';
+    this.JavascriptLoader = (function() {
+        function JavascriptLoader() {
+        }
+
+        /**
+         * Set of library functions that provide common interface for javascript loading
+         * for all module types. All functionality provided by JavascriptLoader should take
+         * place at module scope, i.e. don't run jQuery over entire page.
+         *
+         * executeModuleScripts:
+         *     Scan the module ('el') for "script_placeholder"s, then:
+         *
+         *     1) Fetch each script from server
+         *     2) Explicitly attach the script to the <head> of document
+         *     3) Explicitly wait for each script to be loaded
+         *     4) Return to callback function when all scripts loaded
+         */
+        JavascriptLoader.executeModuleScripts = function(el, callback) {
+            var callbackCalled, completed, completionHandlerGenerator, loaded, placeholders;
+            if (!callback) {
+                callback = null; // eslint-disable-line no-param-reassign
+            }
+            placeholders = el.find('.script_placeholder');
+            if (placeholders.length === 0) {
+                if (callback !== null) {
+                    callback();
+                }
+                return [];
+            }
+            // TODO: Verify the execution order of multiple placeholders
+            completed = (function() {
+                var i, ref, results;
+                results = [];
+                for (i = 1, ref = placeholders.length; ref >= 1 ? i <= ref : i >= ref; ref >= 1 ? ++i : --i) {
+                    results.push(false);
+                }
+                return results;
+            }());
+            callbackCalled = false;
+            completionHandlerGenerator = function(index) {
+                return function() {
+                    var allComplete, flag, i, len;
+                    allComplete = true;
+                    completed[index] = true;
+                    for (i = 0, len = completed.length; i < len; i++) {
+                        flag = completed[i];
+                        if (!flag) {
+                            allComplete = false;
+                            break;
+                        }
+                    }
+                    if (allComplete && !callbackCalled) {
+                        callbackCalled = true;
+                        if (callback !== null) {
+                            return callback();
+                        }
+                    }
+                    return undefined;
+                };
+            };
+            // Keep a map of what sources we're loaded from, and don't do it twice.
+            loaded = {};
+            return placeholders.each(function(index, placeholder) {
+                var s, src;
+                // TODO: Check if the script already exists in DOM. If so, (1) copy it
+                // into memory; (2) delete the DOM script element; (3) reappend it.
+                // This would prevent memory bloat and save a network request.
+                src = $(placeholder).attr('data-src');
+                if (!(src in loaded)) {
+                    loaded[src] = true;
+                    s = document.createElement('script');
+                    s.setAttribute('src', src);
+                    s.setAttribute('type', 'text/javascript');
+                    s.onload = completionHandlerGenerator(index);
+                    // Need to use the DOM elements directly or the scripts won't execute properly.
+                    $('head')[0].appendChild(s);
+                } else {
+                    // just call the completion callback directly, without reloading the file
+                    completionHandlerGenerator(index)();
+                }
+                return $(placeholder).remove();
+            });
+        };
+
+        return JavascriptLoader;
+    }());
+}).call(this);