toolkit/identity/LogUtils.jsm

branch
TOR_BUG_3246
changeset 7
129ffea94266
equal deleted inserted replaced
-1:000000000000 0:236c026f5af6
1 /* -*- Mode: js2; js2-basic-offset: 2; indent-tabs-mode: nil; -*- */
2 /* vim: set ft=javascript ts=2 et sw=2 tw=80: */
3 /* This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
5 * You can obtain one at http://mozilla.org/MPL/2.0/. */
6
7 "use strict";
8
9 this.EXPORTED_SYMBOLS = ["Logger"];
10 const PREF_DEBUG = "toolkit.identity.debug";
11
12 const Cu = Components.utils;
13 const Ci = Components.interfaces;
14 const Cc = Components.classes;
15 const Cr = Components.results;
16
17 Cu.import("resource://gre/modules/XPCOMUtils.jsm");
18 Cu.import("resource://gre/modules/Services.jsm");
19
20 function IdentityLogger() {
21 Services.prefs.addObserver(PREF_DEBUG, this, false);
22 this._debug = Services.prefs.getBoolPref(PREF_DEBUG);
23 return this;
24 }
25
26 IdentityLogger.prototype = {
27 QueryInterface: XPCOMUtils.generateQI([Ci.nsISupports, Ci.nsIObserver]),
28
29 observe: function observe(aSubject, aTopic, aData) {
30 switch(aTopic) {
31 case "nsPref:changed":
32 this._debug = Services.prefs.getBoolPref(PREF_DEBUG);
33 break;
34
35 case "quit-application-granted":
36 Services.prefs.removeObserver(PREF_DEBUG, this);
37 break;
38
39 default:
40 this.log("Logger observer", "Unknown topic:", aTopic);
41 break;
42 }
43 },
44
45 _generateLogMessage: function _generateLogMessage(aPrefix, args) {
46 // create a string representation of a list of arbitrary things
47 let strings = [];
48
49 // XXX bug 770418 - args look like flattened array, not list of strings
50
51 args.forEach(function(arg) {
52 if (typeof arg === 'string') {
53 strings.push(arg);
54 } else if (typeof arg === 'undefined') {
55 strings.push('undefined');
56 } else if (arg === null) {
57 strings.push('null');
58 } else {
59 try {
60 strings.push(JSON.stringify(arg, null, 2));
61 } catch(err) {
62 strings.push("<<something>>");
63 }
64 }
65 });
66 return 'Identity ' + aPrefix + ': ' + strings.join(' ');
67 },
68
69 /**
70 * log() - utility function to print a list of arbitrary things
71 *
72 * Enable with about:config pref toolkit.identity.debug
73 */
74 log: function log(aPrefix, ...args) {
75 if (!this._debug) {
76 return;
77 }
78 let output = this._generateLogMessage(aPrefix, args);
79 dump(output + "\n");
80
81 // Additionally, make the output visible in the Error Console
82 Services.console.logStringMessage(output);
83 },
84
85 /**
86 * reportError() - report an error through component utils as well as
87 * our log function
88 */
89 reportError: function reportError(aPrefix, ...aArgs) {
90 let prefix = aPrefix + ' ERROR';
91
92 // Report the error in the browser
93 let output = this._generateLogMessage(aPrefix, aArgs);
94 Cu.reportError(output);
95 dump("ERROR: " + output + "\n");
96 for (let frame = Components.stack.caller; frame; frame = frame.caller) {
97 dump(frame + "\n");
98 }
99 }
100
101 };
102
103 this.Logger = new IdentityLogger();

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