Introduce JSON parse utility function with error handling (#6401)

* Introduce JSON parse utility function with error handling

Fixes #6400

* Fix typo

boot/boot.js

@@ -409,6 +409,19 @@ $tw.utils.parseFields = function(text,fields) {
 	return fields;
 };
 
+// Safely parse a string as JSON
+$tw.utils.parseJSONSafe = function(text,defaultJSON) {
+	try {
+		return JSON.parse(text);
+	} catch(e) {
+		if(typeof defaultJSON === "function") {
+			return defaultJSON(e);
+		} else {
+			return defaultJSON || {};
+		}
+	}
+};
+
 /*
 Resolves a source filepath delimited with `/` relative to a specified absolute root filepath.
 In relative paths, the special folder name `..` refers to immediate parent directory, and the
@@ -1322,7 +1335,7 @@ $tw.Wiki = function(options) {
 			var tiddler = tiddlers[title];
 			if(tiddler) {
 				if(tiddler.fields.type === "application/json" && tiddler.hasField("plugin-type") && tiddler.fields.text) {
-					pluginInfo[tiddler.fields.title] = JSON.parse(tiddler.fields.text);
+					pluginInfo[tiddler.fields.title] = $tw.utils.parseJSONSafe(tiddler.fields.text);
 					results.modifiedPlugins.push(tiddler.fields.title);
 				}
 			} else {
@@ -1455,7 +1468,7 @@ $tw.Wiki.prototype.defineTiddlerModules = function() {
 					}
 					break;
 				case "application/json":
-					$tw.modules.define(tiddler.fields.title,tiddler.fields["module-type"],JSON.parse(tiddler.fields.text));
+					$tw.modules.define(tiddler.fields.title,tiddler.fields["module-type"],$tw.utils.parseJSONSafe(tiddler.fields.text));
 					break;
 				case "application/x-tiddler-dictionary":
 					$tw.modules.define(tiddler.fields.title,tiddler.fields["module-type"],$tw.utils.parseFields(tiddler.fields.text));
@@ -1644,12 +1657,7 @@ $tw.modules.define("$:/boot/tiddlerdeserializer/json","tiddlerdeserializer",{
 				}
 				return true;
 			},
-			data = {};
+			data = $tw.utils.parseJSONSafe(text);
-		try {
-			data = JSON.parse(text);			
-		} catch(e) {
-			// Ignore JSON parse errors
-		}
 		if($tw.utils.isArray(data) && isTiddlerArrayValid(data)) {
 			return data;
 		} else if(isTiddlerValid(data)) {
@@ -1689,7 +1697,7 @@ $tw.boot.decryptEncryptedTiddlers = function(callback) {
 				$tw.crypto.setPassword(data.password);
 				var decryptedText = $tw.crypto.decrypt(encryptedText);
 				if(decryptedText) {
-					var json = JSON.parse(decryptedText);
+					var json = $tw.utils.parseJSONSafe(decryptedText);
 					for(var title in json) {
 						$tw.preloadTiddler(json[title]);
 					}
@@ -1889,7 +1897,7 @@ filepath: pathname of the directory containing the specification file
 $tw.loadTiddlersFromSpecification = function(filepath,excludeRegExp) {
 	var tiddlers = [];
 	// Read the specification
-	var filesInfo = JSON.parse(fs.readFileSync(filepath + path.sep + "tiddlywiki.files","utf8"));
+	var filesInfo = $tw.utils.parseJSONSafe(fs.readFileSync(filepath + path.sep + "tiddlywiki.files","utf8"));
 	// Helper to process a file
 	var processFile = function(filename,isTiddlerFile,fields,isEditableFile) {
 		var extInfo = $tw.config.fileExtensionInfo[path.extname(filename)],
@@ -2019,7 +2027,7 @@ $tw.loadPluginFolder = function(filepath,excludeRegExp) {
 			console.log("Warning: missing plugin.info file in " + filepath);
 			return null;
 		}
-		var pluginInfo = JSON.parse(fs.readFileSync(infoPath,"utf8"));
+		var pluginInfo = $tw.utils.parseJSONSafe(fs.readFileSync(infoPath,"utf8"));
 		// Read the plugin files
 		var pluginFiles = $tw.loadTiddlersFromPath(filepath,excludeRegExp);
 		// Save the plugin tiddlers into the plugin info
@@ -2136,7 +2144,7 @@ $tw.loadWikiTiddlers = function(wikiPath,options) {
 		pluginFields;
 	// Bail if we don't have a wiki info file
 	if(fs.existsSync(wikiInfoPath)) {
-		wikiInfo = JSON.parse(fs.readFileSync(wikiInfoPath,"utf8"));
+		wikiInfo = $tw.utils.parseJSONSafe(fs.readFileSync(wikiInfoPath,"utf8"));
 	} else {
 		return null;
 	}

core/modules/commands/init.js

@@ -48,7 +48,7 @@ Command.prototype.execute = function() {
 	}
 	// Tweak the tiddlywiki.info to remove any included wikis
 	var packagePath = $tw.boot.wikiPath + "/tiddlywiki.info",
-		packageJson = JSON.parse(fs.readFileSync(packagePath));
+		packageJson = $tw.utils.parseJSONSafe(fs.readFileSync(packagePath));
 	delete packageJson.includeWikis;
 	fs.writeFileSync(packagePath,JSON.stringify(packageJson,null,$tw.config.preferences.jsonSpaces));
 	return null;

core/modules/commands/savelibrarytiddlers.js

@@ -69,7 +69,7 @@ Command.prototype.execute = function() {
 		$tw.utils.createFileDirectories(pathname);
 		fs.writeFileSync(pathname,JSON.stringify(tiddler),"utf8");
 		// Collect the skinny list data
-		var pluginTiddlers = JSON.parse(tiddler.text),
+		var pluginTiddlers = $tw.utils.parseJSONSafe(tiddler.text),
 			readmeContent = (pluginTiddlers.tiddlers[title + "/readme"] || {}).text,
 			doesRequireReload = !!self.commander.wiki.doesPluginInfoRequireReload(pluginTiddlers),
 			iconTiddler = pluginTiddlers.tiddlers[title + "/icon"] || {},

core/modules/commands/savewikifolder.js

@@ -151,7 +151,7 @@ WikiFolderMaker.prototype.saveCustomPlugin = function(pluginTiddler) {
 		pluginInfo = pluginTiddler.getFieldStrings({exclude: ["text","type"]});
 	this.saveJSONFile(directory + path.sep + "plugin.info",pluginInfo);
 	self.log("Writing " + directory + path.sep + "plugin.info: " + JSON.stringify(pluginInfo,null,$tw.config.preferences.jsonSpaces));
-	var pluginTiddlers = JSON.parse(pluginTiddler.fields.text).tiddlers; // A hashmap of tiddlers in the plugin
+	var pluginTiddlers = $tw.utils.parseJSONSafe(pluginTiddler.fields.text).tiddlers; // A hashmap of tiddlers in the plugin
 	$tw.utils.each(pluginTiddlers,function(tiddler) {
 		self.saveTiddler(directory,new $tw.Tiddler(tiddler));
 	});

core/modules/deserializers.js

@@ -17,16 +17,13 @@ exports["application/x-tiddler-html-div"] = function(text,fields) {
 };
 
 exports["application/json"] = function(text,fields) {
-	var incoming,
+	var results = [],
-		results = [];
+		incoming = $tw.utils.parseJSONSafe(text,function(err) {
-	try {
+			return [{
-		incoming = JSON.parse(text);
+				title: "JSON error: " + err,
-	} catch(e) {
+				text: ""
-		incoming = [{
+			}];
-			title: "JSON error: " + e,
+		});
-			text: ""
-		}]
-	}
 	if(!$tw.utils.isArray(incoming)) {
 		incoming = [incoming];
 	}

core/modules/pluginswitcher.js

@@ -52,7 +52,7 @@ PluginSwitcher.prototype.switchPlugins = function() {
 			var tiddler = self.wiki.getTiddler(title);
 			if(tiddler && tiddler.isPlugin() && plugins.indexOf(title) === -1) {
 				plugins.push(title);
-				var pluginInfo = JSON.parse(self.wiki.getTiddlerText(title)),
+				var pluginInfo = $tw.utils.parseJSONSafe(self.wiki.getTiddlerText(title)),
 					dependents = $tw.utils.parseStringArray(tiddler.fields.dependents || "");
 				$tw.utils.each(dependents,function(title) {
 					accumulatePlugin(title);

core/modules/savers/gitea.js

@@ -61,7 +61,7 @@ GiteaSaver.prototype.save = function(text,method,callback) {
 			}
 			var use_put = true;
 			if(xhr.status !== 404) {
-				getResponseData = JSON.parse(getResponseDataJson);
+				getResponseData = $tw.utils.parseJSONSafe(getResponseDataJson);
 				$tw.utils.each(getResponseData,function(details) {
 					if(details.name === filename) {
 						sha = details.sha;
@@ -104,7 +104,7 @@ GiteaSaver.prototype.upload = function(uri,method,headers,data,callback) {
 			if(err) {
 				return callback(err);
 			}
-			var putResponseData = JSON.parse(putResponseDataJson);
+			var putResponseData = $tw.utils.parseJSONSafe(putResponseDataJson);
 			callback(null);
 		}
 	});

core/modules/savers/github.js

@@ -61,7 +61,7 @@ GitHubSaver.prototype.save = function(text,method,callback) {
 				return callback(err);
 			}
 			if(xhr.status !== 404) {
-				getResponseData = JSON.parse(getResponseDataJson);
+				getResponseData = $tw.utils.parseJSONSafe(getResponseDataJson);
 				$tw.utils.each(getResponseData,function(details) {
 					if(details.name === filename) {
 						sha = details.sha;
@@ -84,7 +84,7 @@ GitHubSaver.prototype.save = function(text,method,callback) {
 					if(err) {
 						return callback(err);
 					}
-					var putResponseData = JSON.parse(putResponseDataJson);
+					var putResponseData = $tw.utils.parseJSONSafe(putResponseDataJson);
 					callback(null);
 				}
 			});

core/modules/savers/gitlab.js

@@ -58,7 +58,7 @@ GitLabSaver.prototype.save = function(text,method,callback) {
 			}
 			var requestType = "POST";
 			if(xhr.status !== 404) {
-				getResponseData = JSON.parse(getResponseDataJson);
+				getResponseData = $tw.utils.parseJSONSafe(getResponseDataJson);
 				$tw.utils.each(getResponseData,function(details) {
 					if(details.name === filename) {
 						requestType = "PUT";
@@ -82,7 +82,7 @@ GitLabSaver.prototype.save = function(text,method,callback) {
 					if(err) {
 						return callback(err);
 					}
-					var putResponseData = JSON.parse(putResponseDataJson);
+					var putResponseData = $tw.utils.parseJSONSafe(putResponseDataJson);
 					callback(null);
 				}
 			});

core/modules/server/routes/put-tiddler.js

@@ -18,7 +18,7 @@ exports.path = /^\/recipes\/default\/tiddlers\/(.+)$/;
 
 exports.handler = function(request,response,state) {
 	var title = $tw.utils.decodeURIComponentSafe(state.params[0]),
-	fields = JSON.parse(state.data);
+	fields = $tw.utils.parseJSONSafe(state.data);
 	// Pull up any subfields in the `fields` object
 	if(fields.fields) {
 		$tw.utils.each(fields.fields,function(field,name) {

core/modules/startup/browser-messaging.js

@@ -152,7 +152,7 @@ exports.startup = function() {
 				if(event.data.status.charAt(0) === "2") {
 					if(event.data.cookies) {
 						if(event.data.cookies.type === "save-info") {
-							var tiddlers = JSON.parse(event.data.body);
+							var tiddlers = $tw.utils.parseJSONSafe(event.data.body);
 							$tw.utils.each(tiddlers,function(tiddler) {
 								$tw.wiki.addTiddler(new $tw.Tiddler($tw.wiki.getCreationFields(),tiddler,{
 									title: event.data.cookies.infoTitlePrefix + event.data.cookies.url + "/" + tiddler.title,
@@ -170,7 +170,7 @@ exports.startup = function() {
 								},$tw.wiki.getModificationFields()));
 							});
 						} else if(event.data.cookies.type === "save-tiddler") {
-							var tiddler = JSON.parse(event.data.body);
+							var tiddler = $tw.utils.parseJSONSafe(event.data.body);
 							$tw.wiki.addTiddler(new $tw.Tiddler(tiddler));
 						}
 					}

core/modules/upgraders/plugins.js

@@ -41,7 +41,7 @@ exports.upgrade = function(wiki,titles,tiddlers) {
 		// Check if we're dealing with a plugin
 		if(incomingTiddler && incomingTiddler["plugin-type"]) {
 			// Check whether the plugin contains JS modules
-			var requiresReload = wiki.doesPluginInfoRequireReload(JSON.parse(incomingTiddler.text)) ? (wiki.getTiddlerText("$:/language/ControlPanel/Plugins/PluginWillRequireReload") + " ") : "";
+			var requiresReload = wiki.doesPluginInfoRequireReload($tw.utils.parseJSONSafe(incomingTiddler.text)) ? (wiki.getTiddlerText("$:/language/ControlPanel/Plugins/PluginWillRequireReload") + " ") : "";
 			messages[title] = requiresReload;
 			if(incomingTiddler.version) {
 				// Upgrade the incoming plugin if it is in the upgrade library

core/modules/utils/crypto.js

@@ -33,7 +33,7 @@ Attempt to extract the tiddlers from an encrypted store area using the current p
 exports.decryptStoreArea = function(encryptedStoreArea,password) {
 	var decryptedText = $tw.crypto.decrypt(encryptedStoreArea,password);
 	if(decryptedText) {
-		var json = JSON.parse(decryptedText),
+		var json = $tw.utils.parseJSONSafe(decryptedText),
 			tiddlers = [];
 		for(var title in json) {
 			if(title !== "$:/isEncrypted") {

core/modules/utils/dom/dragndrop.js

@@ -198,7 +198,7 @@ var importDataTypes = [
 ];
 
 function parseJSONTiddlers(json,fallbackTitle) {
-	var data = JSON.parse(json);
+	var data = $tw.utils.parseJSONSafe(json);
 	if(!$tw.utils.isArray(data)) {
 		data = [data];
 	}

core/modules/utils/edition-info.js

@@ -30,11 +30,7 @@ exports.getEditionInfo = function() {
 				var entry = entries[entryIndex];
 				// Check if directories have a valid tiddlywiki.info
 				if(!editionInfo[entry] && $tw.utils.isDirectory(path.resolve(editionPath,entry))) {
-					var info;
+					var info = $tw.utils.parseJSONSafe(fs.readFileSync(path.resolve(editionPath,entry,"tiddlywiki.info"),"utf8"),null);
-					try {
-						info = JSON.parse(fs.readFileSync(path.resolve(editionPath,entry,"tiddlywiki.info"),"utf8"));
-					} catch(ex) {
-					}
 					if(info) {
 						editionInfo[entry] = info;
 					}

core/modules/utils/pluginmaker.js

@@ -24,10 +24,8 @@ exports.repackPlugin = function(title,additionalTiddlers,excludeTiddlers) {
 		throw "No such tiddler as " + title;
 	}
 	// Extract the JSON
-	var jsonPluginTiddler;
+	var jsonPluginTiddler = $tw.utils.parseJSONSafe(pluginTiddler.fields.text,null);
-	try {
+	if(!jsonPluginTiddler) {
-		jsonPluginTiddler = JSON.parse(pluginTiddler.fields.text);
-	} catch(e) {
 		throw "Cannot parse plugin tiddler " + title + "\n" + $tw.language.getString("Error/Caption") + ": " + e;
 	}
 	// Get the list of tiddlers

core/modules/widgets/navigator.js

@@ -498,11 +498,7 @@ NavigatorWidget.prototype.handleNewTiddlerEvent = function(event) {
 // Import JSON tiddlers into a pending import tiddler
 NavigatorWidget.prototype.handleImportTiddlersEvent = function(event) {
 	// Get the tiddlers
-	var tiddlers = [];
+	var tiddlers = $tw.utils.parseJSONSafe(event.param,[]);
-	try {
-		tiddlers = JSON.parse(event.param);
-	} catch(e) {
-	}
 	// Get the current $:/Import tiddler
 	var importTitle = event.importTitle ? event.importTitle : IMPORT_TITLE,
 		importTiddler = this.wiki.getTiddler(importTitle),

core/modules/wiki.js

@@ -833,12 +833,7 @@ exports.getTiddlerData = function(titleOrTiddler,defaultData) {
 		switch(tiddler.fields.type) {
 			case "application/json":
 				// JSON tiddler
-				try {
+				return $tw.utils.parseJSONSafe(tiddler.fields.text,defaultData);
-					data = JSON.parse(tiddler.fields.text);
-				} catch(ex) {
-					return defaultData;
-				}
-				return data;
 			case "application/x-tiddler-dictionary":
 				return $tw.utils.parseFields(tiddler.fields.text);
 		}