menu.js: Can load http(s) URLs in the file menu

It will also allow to open distant files. For instance it will be very helpful in environment
reviews to test on different files.

browser/js/menu.js

@@ -40,7 +40,7 @@ function initMenu () {
                 type: "GET",
                 timeout: 5000,
                 crossDomain: true,
-                url: config.file_menu.path + config.file_menu.file[0],
+                url: prepend_path_if_not_web(config.file_menu.file[0], config.file_menu.path),
                 success: function (result) {
                     $('#static_file_menu').css("display", "")
                     var demo_file = document.getElementById("fileSelector").firstChild
@@ -50,7 +50,8 @@ function initMenu () {
                         var a = document.createElement('a');
                         a.className = "buttonSelector"
                         a.onclick = function () {
-                            m.loadDataUrl(config.file_menu.path + config.file_menu.file[i])
+                            var url = prepend_path_if_not_web(config.file_menu.file[i], config.file_menu.path);
+                            m.loadDataUrl(url)
                         }
 
                         a.appendChild(document.createTextNode(config.file_menu.file[i]))

browser/js/tools.js

@@ -110,6 +110,20 @@ function correctIMGTPositionsForInsertions(data) {
     }
 }
 
+/**
+ * Prepend a path before a filepath if that filepath is not a web path.
+ * @param file: a path to a file may be relative, absolute or web path
+ * @param path: a directory path
+ * @return file iff it is a web path (ie. starting with http or ftp)
+ *         path + file otherwise
+ */
+function prepend_path_if_not_web(file, path) {
+    if (file.startsWith('http') || file.startsWith('ftp')) {
+        return file;
+    }
+    return path + file;
+}
+
 /**
  * Take in parameter the JSON result of CloneDB for one clone
  * Return a hash whose keys are URLs to sample sets and configs.

browser/test/QUnit/testFiles/tools_test.js

@@ -54,6 +54,12 @@ QUnit.test("test rounding functions", function(assert) {
     }
 );
 
+QUnit.test("prepend_path_if_not_web", function(assert) {
+    assert.equal(prepend_path_if_not_web('toto', 'tata/'), 'tata/toto');
+    assert.equal(prepend_path_if_not_web('toto', 'http://toto'), 'http://toto');
+    assert.equal(prepend_path_if_not_web('toto', 'ftp://toto'), 'ftp://toto');
+});
+
 QUnit.test("processCloneDBContents", function(assert) {
     var emptyResult = [];
     assert.deepEqual(processCloneDBContents(emptyResult), {'original': [],