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Diffstat (limited to 'toolkit/modules/Log.jsm')
| -rw-r--r-- | toolkit/modules/Log.jsm | 747 |
1 files changed, 747 insertions, 0 deletions
diff --git a/toolkit/modules/Log.jsm b/toolkit/modules/Log.jsm new file mode 100644 index 0000000000..03111b6951 --- /dev/null +++ b/toolkit/modules/Log.jsm @@ -0,0 +1,747 @@ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +"use strict"; + +var EXPORTED_SYMBOLS = ["Log"]; + +const { XPCOMUtils } = ChromeUtils.import( + "resource://gre/modules/XPCOMUtils.jsm" +); +ChromeUtils.defineModuleGetter( + this, + "Services", + "resource://gre/modules/Services.jsm" +); +const INTERNAL_FIELDS = new Set(["_level", "_message", "_time", "_namespace"]); + +/* + * Dump a message everywhere we can if we have a failure. + */ +function dumpError(text) { + dump(text + "\n"); + Cu.reportError(text); +} + +var Log = { + Level: { + Fatal: 70, + Error: 60, + Warn: 50, + Info: 40, + Config: 30, + Debug: 20, + Trace: 10, + All: -1, // We don't want All to be falsy. + Desc: { + 70: "FATAL", + 60: "ERROR", + 50: "WARN", + 40: "INFO", + 30: "CONFIG", + 20: "DEBUG", + 10: "TRACE", + "-1": "ALL", + }, + Numbers: { + FATAL: 70, + ERROR: 60, + WARN: 50, + INFO: 40, + CONFIG: 30, + DEBUG: 20, + TRACE: 10, + ALL: -1, + }, + }, + + get repository() { + delete Log.repository; + Log.repository = new LoggerRepository(); + return Log.repository; + }, + set repository(value) { + delete Log.repository; + Log.repository = value; + }, + + _formatError(e) { + let result = String(e); + if (e.fileName) { + let loc = [e.fileName]; + if (e.lineNumber) { + loc.push(e.lineNumber); + } + if (e.columnNumber) { + loc.push(e.columnNumber); + } + result += `(${loc.join(":")})`; + } + return `${result} ${Log.stackTrace(e)}`; + }, + + // This is for back compatibility with services/common/utils.js; we duplicate + // some of the logic in ParameterFormatter + exceptionStr(e) { + if (!e) { + return String(e); + } + if (e instanceof Ci.nsIException) { + return `${e} ${Log.stackTrace(e)}`; + } else if (isError(e)) { + return Log._formatError(e); + } + // else + let message = e.message || e; + return `${message} ${Log.stackTrace(e)}`; + }, + + stackTrace(e) { + // Wrapped nsIException + if (e.location) { + let frame = e.location; + let output = []; + while (frame) { + // Works on frames or exceptions, munges file:// URIs to shorten the paths + // FIXME: filename munging is sort of hackish, might be confusing if + // there are multiple extensions with similar filenames + let str = "<file:unknown>"; + + let file = frame.filename || frame.fileName; + if (file) { + str = file.replace(/^(?:chrome|file):.*?([^\/\.]+\.\w+)$/, "$1"); + } + + if (frame.lineNumber) { + str += ":" + frame.lineNumber; + } + + if (frame.name) { + str = frame.name + "()@" + str; + } + + if (str) { + output.push(str); + } + frame = frame.caller; + } + return `Stack trace: ${output.join("\n")}`; + } + // Standard JS exception + if (e.stack) { + let stack = e.stack; + return ( + "JS Stack trace: " + + stack.trim().replace(/@[^@]*?([^\/\.]+\.\w+:)/g, "@$1") + ); + } + + return "No traceback available"; + }, +}; + +/* + * LogMessage + * Encapsulates a single log event's data + */ +class LogMessage { + constructor(loggerName, level, message, params) { + this.loggerName = loggerName; + this.level = level; + /* + * Special case to handle "log./level/(object)", for example logging a caught exception + * without providing text or params like: catch(e) { logger.warn(e) } + * Treating this as an empty text with the object in the 'params' field causes the + * object to be formatted properly by BasicFormatter. + */ + if ( + !params && + message && + typeof message == "object" && + typeof message.valueOf() != "string" + ) { + this.message = null; + this.params = message; + } else { + // If the message text is empty, or a string, or a String object, normal handling + this.message = message; + this.params = params; + } + + // The _structured field will correspond to whether this message is to + // be interpreted as a structured message. + this._structured = this.params && this.params.action; + this.time = Date.now(); + } + + get levelDesc() { + if (this.level in Log.Level.Desc) { + return Log.Level.Desc[this.level]; + } + return "UNKNOWN"; + } + + toString() { + let msg = `${this.time} ${this.level} ${this.message}`; + if (this.params) { + msg += ` ${JSON.stringify(this.params)}`; + } + return `LogMessage [${msg}]`; + } +} + +/* + * Logger + * Hierarchical version. Logs to all appenders, assigned or inherited + */ + +class Logger { + constructor(name, repository) { + if (!repository) { + repository = Log.repository; + } + this._name = name; + this.children = []; + this.ownAppenders = []; + this.appenders = []; + this._repository = repository; + + this._levelPrefName = null; + this._levelPrefValue = null; + this._level = null; + this._parent = null; + } + + get name() { + return this._name; + } + + get level() { + if (this._levelPrefName) { + // We've been asked to use a preference to configure the logs. If the + // pref has a value we use it, otherwise we continue to use the parent. + const lpv = this._levelPrefValue; + if (lpv) { + const levelValue = Log.Level[lpv]; + if (levelValue) { + // stash it in _level just in case a future value of the pref is + // invalid, in which case we end up continuing to use this value. + this._level = levelValue; + return levelValue; + } + } else { + // in case the pref has transitioned from a value to no value, we reset + // this._level and fall through to using the parent. + this._level = null; + } + } + if (this._level != null) { + return this._level; + } + if (this.parent) { + return this.parent.level; + } + dumpError("Log warning: root logger configuration error: no level defined"); + return Log.Level.All; + } + set level(level) { + if (this._levelPrefName) { + // I guess we could honor this by nuking this._levelPrefValue, but it + // almost certainly implies confusion, so we'll warn and ignore. + dumpError( + `Log warning: The log '${this.name}' is configured to use ` + + `the preference '${this._levelPrefName}' - you must adjust ` + + `the level by setting this preference, not by using the ` + + `level setter` + ); + return; + } + this._level = level; + } + + get parent() { + return this._parent; + } + set parent(parent) { + if (this._parent == parent) { + return; + } + // Remove ourselves from parent's children + if (this._parent) { + let index = this._parent.children.indexOf(this); + if (index != -1) { + this._parent.children.splice(index, 1); + } + } + this._parent = parent; + parent.children.push(this); + this.updateAppenders(); + } + + manageLevelFromPref(prefName) { + if (prefName == this._levelPrefName) { + // We've already configured this log with an observer for that pref. + return; + } + if (this._levelPrefName) { + dumpError( + `The log '${this.name}' is already configured with the ` + + `preference '${this._levelPrefName}' - ignoring request to ` + + `also use the preference '${prefName}'` + ); + return; + } + this._levelPrefName = prefName; + XPCOMUtils.defineLazyPreferenceGetter(this, "_levelPrefValue", prefName); + } + + updateAppenders() { + if (this._parent) { + let notOwnAppenders = this._parent.appenders.filter(function(appender) { + return !this.ownAppenders.includes(appender); + }, this); + this.appenders = notOwnAppenders.concat(this.ownAppenders); + } else { + this.appenders = this.ownAppenders.slice(); + } + + // Update children's appenders. + for (let i = 0; i < this.children.length; i++) { + this.children[i].updateAppenders(); + } + } + + addAppender(appender) { + if (this.ownAppenders.includes(appender)) { + return; + } + this.ownAppenders.push(appender); + this.updateAppenders(); + } + + removeAppender(appender) { + let index = this.ownAppenders.indexOf(appender); + if (index == -1) { + return; + } + this.ownAppenders.splice(index, 1); + this.updateAppenders(); + } + + _unpackTemplateLiteral(string, params) { + if (!Array.isArray(params)) { + // Regular log() call. + return [string, params]; + } + + if (!Array.isArray(string)) { + // Not using template literal. However params was packed into an array by + // the this.[level] call, so we need to unpack it here. + return [string, params[0]]; + } + + // We're using template literal format (logger.warn `foo ${bar}`). Turn the + // template strings into one string containing "${0}"..."${n}" tokens, and + // feed it to the basic formatter. The formatter will treat the numbers as + // indices into the params array, and convert the tokens to the params. + + if (!params.length) { + // No params; we need to set params to undefined, so the formatter + // doesn't try to output the params array. + return [string[0], undefined]; + } + + let concat = string[0]; + for (let i = 0; i < params.length; i++) { + concat += `\${${i}}${string[i + 1]}`; + } + return [concat, params]; + } + + log(level, string, params) { + if (this.level > level) { + return; + } + + // Hold off on creating the message object until we actually have + // an appender that's responsible. + let message; + let appenders = this.appenders; + for (let appender of appenders) { + if (appender.level > level) { + continue; + } + if (!message) { + [string, params] = this._unpackTemplateLiteral(string, params); + message = new LogMessage(this._name, level, string, params); + } + appender.append(message); + } + } + + fatal(string, ...params) { + this.log(Log.Level.Fatal, string, params); + } + error(string, ...params) { + this.log(Log.Level.Error, string, params); + } + warn(string, ...params) { + this.log(Log.Level.Warn, string, params); + } + info(string, ...params) { + this.log(Log.Level.Info, string, params); + } + config(string, ...params) { + this.log(Log.Level.Config, string, params); + } + debug(string, ...params) { + this.log(Log.Level.Debug, string, params); + } + trace(string, ...params) { + this.log(Log.Level.Trace, string, params); + } +} + +/* + * LoggerRepository + * Implements a hierarchy of Loggers + */ + +class LoggerRepository { + constructor() { + this._loggers = {}; + this._rootLogger = null; + } + + get rootLogger() { + if (!this._rootLogger) { + this._rootLogger = new Logger("root", this); + this._rootLogger.level = Log.Level.All; + } + return this._rootLogger; + } + set rootLogger(logger) { + throw new Error("Cannot change the root logger"); + } + + _updateParents(name) { + let pieces = name.split("."); + let cur, parent; + + // find the closest parent + // don't test for the logger name itself, as there's a chance it's already + // there in this._loggers + for (let i = 0; i < pieces.length - 1; i++) { + if (cur) { + cur += "." + pieces[i]; + } else { + cur = pieces[i]; + } + if (cur in this._loggers) { + parent = cur; + } + } + + // if we didn't assign a parent above, there is no parent + if (!parent) { + this._loggers[name].parent = this.rootLogger; + } else { + this._loggers[name].parent = this._loggers[parent]; + } + + // trigger updates for any possible descendants of this logger + for (let logger in this._loggers) { + if (logger != name && logger.indexOf(name) == 0) { + this._updateParents(logger); + } + } + } + + /** + * Obtain a named Logger. + * + * The returned Logger instance for a particular name is shared among + * all callers. In other words, if two consumers call getLogger("foo"), + * they will both have a reference to the same object. + * + * @return Logger + */ + getLogger(name) { + if (name in this._loggers) { + return this._loggers[name]; + } + this._loggers[name] = new Logger(name, this); + this._updateParents(name); + return this._loggers[name]; + } + + /** + * Obtain a Logger that logs all string messages with a prefix. + * + * A common pattern is to have separate Logger instances for each instance + * of an object. But, you still want to distinguish between each instance. + * Since Log.repository.getLogger() returns shared Logger objects, + * monkeypatching one Logger modifies them all. + * + * This function returns a new object with a prototype chain that chains + * up to the original Logger instance. The new prototype has log functions + * that prefix content to each message. + * + * @param name + * (string) The Logger to retrieve. + * @param prefix + * (string) The string to prefix each logged message with. + */ + getLoggerWithMessagePrefix(name, prefix) { + let log = this.getLogger(name); + + let proxy = Object.create(log); + proxy.log = (level, string, params) => { + if (Array.isArray(string) && Array.isArray(params)) { + // Template literal. + // We cannot change the original array, so create a new one. + string = [prefix + string[0]].concat(string.slice(1)); + } else { + string = prefix + string; // Regular string. + } + return log.log(level, string, params); + }; + return proxy; + } +} + +/* + * Formatters + * These massage a LogMessage into whatever output is desired. + */ + +// Basic formatter that doesn't do anything fancy. +class BasicFormatter { + constructor(dateFormat) { + if (dateFormat) { + this.dateFormat = dateFormat; + } + this.parameterFormatter = new ParameterFormatter(); + } + + /** + * Format the text of a message with optional parameters. + * If the text contains ${identifier}, replace that with + * the value of params[identifier]; if ${}, replace that with + * the entire params object. If no params have been substituted + * into the text, format the entire object and append that + * to the message. + */ + formatText(message) { + let params = message.params; + if (typeof params == "undefined") { + return message.message || ""; + } + // Defensive handling of non-object params + // We could add a special case for NSRESULT values here... + let pIsObject = typeof params == "object" || typeof params == "function"; + + // if we have params, try and find substitutions. + if (this.parameterFormatter) { + // have we successfully substituted any parameters into the message? + // in the log message + let subDone = false; + let regex = /\$\{(\S*?)\}/g; + let textParts = []; + if (message.message) { + textParts.push( + message.message.replace(regex, (_, sub) => { + // ${foo} means use the params['foo'] + if (sub) { + if (pIsObject && sub in message.params) { + subDone = true; + return this.parameterFormatter.format(message.params[sub]); + } + return "${" + sub + "}"; + } + // ${} means use the entire params object. + subDone = true; + return this.parameterFormatter.format(message.params); + }) + ); + } + if (!subDone) { + // There were no substitutions in the text, so format the entire params object + let rest = this.parameterFormatter.format(message.params); + if (rest !== null && rest != "{}") { + textParts.push(rest); + } + } + return textParts.join(": "); + } + return undefined; + } + + format(message) { + return ( + message.time + + "\t" + + message.loggerName + + "\t" + + message.levelDesc + + "\t" + + this.formatText(message) + ); + } +} + +/** + * Test an object to see if it is a Mozilla JS Error. + */ +function isError(aObj) { + return ( + aObj && + typeof aObj == "object" && + "name" in aObj && + "message" in aObj && + "fileName" in aObj && + "lineNumber" in aObj && + "stack" in aObj + ); +} + +/* + * Parameter Formatters + * These massage an object used as a parameter for a LogMessage into + * a string representation of the object. + */ + +class ParameterFormatter { + constructor() { + this._name = "ParameterFormatter"; + } + + format(ob) { + try { + if (ob === undefined) { + return "undefined"; + } + if (ob === null) { + return "null"; + } + // Pass through primitive types and objects that unbox to primitive types. + if ( + (typeof ob != "object" || typeof ob.valueOf() != "object") && + typeof ob != "function" + ) { + return ob; + } + if (ob instanceof Ci.nsIException) { + return `${ob} ${Log.stackTrace(ob)}`; + } else if (isError(ob)) { + return Log._formatError(ob); + } + // Just JSONify it. Filter out our internal fields and those the caller has + // already handled. + return JSON.stringify(ob, (key, val) => { + if (INTERNAL_FIELDS.has(key)) { + return undefined; + } + return val; + }); + } catch (e) { + dumpError( + `Exception trying to format object for log message: ${Log.exceptionStr( + e + )}` + ); + } + // Fancy formatting failed. Just toSource() it - but even this may fail! + try { + return ob.toSource(); + } catch (_) {} + try { + return String(ob); + } catch (_) { + return "[object]"; + } + } +} + +/* + * Appenders + * These can be attached to Loggers to log to different places + * Simply subclass and override doAppend to implement a new one + */ + +class Appender { + constructor(formatter) { + this.level = Log.Level.All; + this._name = "Appender"; + this._formatter = formatter || new BasicFormatter(); + } + + append(message) { + if (message) { + this.doAppend(this._formatter.format(message)); + } + } + + toString() { + return `${this._name} [level=${this.level}, formatter=${this._formatter}]`; + } +} + +/* + * DumpAppender + * Logs to standard out + */ + +class DumpAppender extends Appender { + constructor(formatter) { + super(formatter); + this._name = "DumpAppender"; + } + + doAppend(formatted) { + dump(formatted + "\n"); + } +} + +/* + * ConsoleAppender + * Logs to the javascript console + */ + +class ConsoleAppender extends Appender { + constructor(formatter) { + super(formatter); + this._name = "ConsoleAppender"; + } + + // XXX this should be replaced with calls to the Browser Console + append(message) { + if (message) { + let m = this._formatter.format(message); + if (message.level > Log.Level.Warn) { + Cu.reportError(m); + return; + } + this.doAppend(m); + } + } + + doAppend(formatted) { + Services.console.logStringMessage(formatted); + } +} + +Object.assign(Log, { + LogMessage, + Logger, + LoggerRepository, + + BasicFormatter, + + Appender, + DumpAppender, + ConsoleAppender, + + ParameterFormatter, +}); |