1 files changed, 331 insertions, 0 deletions
diff --git a/services/common/logmanager.js b/services/common/logmanager.js
new file mode 100644
index 000000000..17e47f9e3
--- /dev/null
+++ b/services/common/logmanager.js
@@ -0,0 +1,331 @@
+/* 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 {classes: Cc, interfaces: Ci, utils: Cu, results: Cr} = Components;
+
+Cu.import("resource://gre/modules/XPCOMUtils.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "Services",
+  "resource://gre/modules/Services.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "FileUtils",
+  "resource://gre/modules/FileUtils.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "Log",
+  "resource://gre/modules/Log.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "OS",
+  "resource://gre/modules/osfile.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "CommonUtils",
+  "resource://services-common/utils.js");
+
+Cu.import("resource://gre/modules/Preferences.jsm");
+Cu.import("resource://gre/modules/Task.jsm");
+
+this.EXPORTED_SYMBOLS = [
+  "LogManager",
+];
+
+const DEFAULT_MAX_ERROR_AGE = 20 * 24 * 60 * 60; // 20 days
+
+// "shared" logs (ie, where the same log name is used by multiple LogManager
+// instances) are a fact of life here - eg, FirefoxAccounts logs are used by
+// both Sync and Reading List.
+// However, different instances have different pref branches, so we need to
+// handle when one pref branch says "Debug" and the other says "Error"
+// So we (a) keep singleton console and dump appenders and (b) keep track
+// of the minimum (ie, most verbose) level and use that.
+// This avoids (a) the most recent setter winning (as that is indeterminate)
+// and (b) multiple dump/console appenders being added to the same log multiple
+// times, which would cause messages to appear twice.
+
+// Singletons used by each instance.
+var formatter;
+var dumpAppender;
+var consoleAppender;
+
+// A set of all preference roots used by all instances.
+var allBranches = new Set();
+
+// A storage appender that is flushable to a file on disk.  Policies for
+// when to flush, to what file, log rotation etc are up to the consumer
+// (although it does maintain a .sawError property to help the consumer decide
+// based on its policies)
+function FlushableStorageAppender(formatter) {
+  Log.StorageStreamAppender.call(this, formatter);
+  this.sawError = false;
+}
+
+FlushableStorageAppender.prototype = {
+  __proto__: Log.StorageStreamAppender.prototype,
+
+  append(message) {
+    if (message.level >= Log.Level.Error) {
+      this.sawError = true;
+    }
+    Log.StorageStreamAppender.prototype.append.call(this, message);
+  },
+
+  reset() {
+    Log.StorageStreamAppender.prototype.reset.call(this);
+    this.sawError = false;
+  },
+
+  // Flush the current stream to a file. Somewhat counter-intuitively, you
+  // must pass a log which will be written to with details of the operation.
+  flushToFile: Task.async(function* (subdirArray, filename, log) {
+    let inStream = this.getInputStream();
+    this.reset();
+    if (!inStream) {
+      log.debug("Failed to flush log to a file - no input stream");
+      return;
+    }
+    log.debug("Flushing file log");
+    log.trace("Beginning stream copy to " + filename + ": " + Date.now());
+    try {
+      yield this._copyStreamToFile(inStream, subdirArray, filename, log);
+      log.trace("onCopyComplete", Date.now());
+    } catch (ex) {
+      log.error("Failed to copy log stream to file", ex);
+    }
+  }),
+
+  /**
+   * Copy an input stream to the named file, doing everything off the main
+   * thread.
+   * subDirArray is an array of path components, relative to the profile
+   * directory, where the file will be created.
+   * outputFileName is the filename to create.
+   * Returns a promise that is resolved on completion or rejected with an error.
+   */
+  _copyStreamToFile: Task.async(function* (inputStream, subdirArray, outputFileName, log) {
+    // The log data could be large, so we don't want to pass it all in a single
+    // message, so use BUFFER_SIZE chunks.
+    const BUFFER_SIZE = 8192;
+
+    // get a binary stream
+    let binaryStream = Cc["@mozilla.org/binaryinputstream;1"].createInstance(Ci.nsIBinaryInputStream);
+    binaryStream.setInputStream(inputStream);
+
+    let outputDirectory = OS.Path.join(OS.Constants.Path.profileDir, ...subdirArray);
+    yield OS.File.makeDir(outputDirectory, { ignoreExisting: true, from: OS.Constants.Path.profileDir });
+    let fullOutputFileName = OS.Path.join(outputDirectory, outputFileName);
+    let output = yield OS.File.open(fullOutputFileName, { write: true} );
+    try {
+      while (true) {
+        let available = binaryStream.available();
+        if (!available) {
+          break;
+        }
+        let chunk = binaryStream.readByteArray(Math.min(available, BUFFER_SIZE));
+        yield output.write(new Uint8Array(chunk));
+      }
+    } finally {
+      try {
+        binaryStream.close(); // inputStream is closed by the binaryStream
+        yield output.close();
+      } catch (ex) {
+        log.error("Failed to close the input stream", ex);
+      }
+    }
+    log.trace("finished copy to", fullOutputFileName);
+  }),
+}
+
+// The public LogManager object.
+function LogManager(prefRoot, logNames, logFilePrefix) {
+  this._prefObservers = [];
+  this.init(prefRoot, logNames, logFilePrefix);
+}
+
+LogManager.prototype = {
+  _cleaningUpFileLogs: false,
+
+  init(prefRoot, logNames, logFilePrefix) {
+    if (prefRoot instanceof Preferences) {
+      this._prefs = prefRoot;
+    } else {
+      this._prefs = new Preferences(prefRoot);
+    }
+
+    this.logFilePrefix = logFilePrefix;
+    if (!formatter) {
+      // Create a formatter and various appenders to attach to the logs.
+      formatter = new Log.BasicFormatter();
+      consoleAppender = new Log.ConsoleAppender(formatter);
+      dumpAppender = new Log.DumpAppender(formatter);
+    }
+
+    allBranches.add(this._prefs._branchStr);
+    // We create a preference observer for all our prefs so they are magically
+    // reflected if the pref changes after creation.
+    let setupAppender = (appender, prefName, defaultLevel, findSmallest = false) => {
+      let observer = newVal => {
+        let level = Log.Level[newVal] || defaultLevel;
+        if (findSmallest) {
+          // As some of our appenders have global impact (ie, there is only one
+          // place 'dump' goes to), we need to find the smallest value from all
+          // prefs controlling this appender.
+          // For example, if consumerA has dump=Debug then consumerB sets
+          // dump=Error, we need to keep dump=Debug so consumerA is respected.
+          for (let branch of allBranches) {
+            let lookPrefBranch = new Preferences(branch);
+            let lookVal = Log.Level[lookPrefBranch.get(prefName)];
+            if (lookVal && lookVal < level) {
+              level = lookVal;
+            }
+          }
+        }
+        appender.level = level;
+      }
+      this._prefs.observe(prefName, observer, this);
+      this._prefObservers.push([prefName, observer]);
+      // and call the observer now with the current pref value.
+      observer(this._prefs.get(prefName));
+      return observer;
+    }
+
+    this._observeConsolePref = setupAppender(consoleAppender, "log.appender.console", Log.Level.Fatal, true);
+    this._observeDumpPref = setupAppender(dumpAppender, "log.appender.dump", Log.Level.Error, true);
+
+    // The file appender doesn't get the special singleton behaviour.
+    let fapp = this._fileAppender = new FlushableStorageAppender(formatter);
+    // the stream gets a default of Debug as the user must go out of their way
+    // to see the stuff spewed to it.
+    this._observeStreamPref = setupAppender(fapp, "log.appender.file.level", Log.Level.Debug);
+
+    // now attach the appenders to all our logs.
+    for (let logName of logNames) {
+      let log = Log.repository.getLogger(logName);
+      for (let appender of [fapp, dumpAppender, consoleAppender]) {
+        log.addAppender(appender);
+      }
+    }
+    // and use the first specified log as a "root" for our log.
+    this._log = Log.repository.getLogger(logNames[0] + ".LogManager");
+  },
+
+  /**
+   * Cleanup this instance
+   */
+  finalize() {
+    for (let [name, pref] of this._prefObservers) {
+      this._prefs.ignore(name, pref, this);
+    }
+    this._prefObservers = [];
+    try {
+      allBranches.delete(this._prefs._branchStr);
+    } catch (e) {}
+    this._prefs = null;
+  },
+
+  get _logFileSubDirectoryEntries() {
+    // At this point we don't allow a custom directory for the logs, nor allow
+    // it to be outside the profile directory.
+    // This returns an array of the the relative directory entries below the
+    // profile dir, and is the directory about:sync-log uses.
+    return ["weave", "logs"];
+  },
+
+  get sawError() {
+    return this._fileAppender.sawError;
+  },
+
+  // Result values for resetFileLog.
+  SUCCESS_LOG_WRITTEN: "success-log-written",
+  ERROR_LOG_WRITTEN: "error-log-written",
+
+  /**
+   * Possibly generate a log file for all accumulated log messages and refresh
+   * the input & output streams.
+   * Whether a "success" or "error" log is written is determined based on
+   * whether an "Error" log entry was written to any of the logs.
+   * Returns a promise that resolves on completion with either null (for no
+   * file written or on error), SUCCESS_LOG_WRITTEN if a "success" log was
+   * written, or ERROR_LOG_WRITTEN if an "error" log was written.
+   */
+  resetFileLog: Task.async(function* () {
+    try {
+      let flushToFile;
+      let reasonPrefix;
+      let reason;
+      if (this._fileAppender.sawError) {
+        reason = this.ERROR_LOG_WRITTEN;
+        flushToFile = this._prefs.get("log.appender.file.logOnError", true);
+        reasonPrefix = "error";
+      } else {
+        reason = this.SUCCESS_LOG_WRITTEN;
+        flushToFile = this._prefs.get("log.appender.file.logOnSuccess", false);
+        reasonPrefix = "success";
+      }
+
+      // might as well avoid creating an input stream if we aren't going to use it.
+      if (!flushToFile) {
+        this._fileAppender.reset();
+        return null;
+      }
+
+      // We have reasonPrefix at the start of the filename so all "error"
+      // logs are grouped in about:sync-log.
+      let filename = reasonPrefix + "-" + this.logFilePrefix + "-" + Date.now() + ".txt";
+      yield this._fileAppender.flushToFile(this._logFileSubDirectoryEntries, filename, this._log);
+
+      // It's not completely clear to markh why we only do log cleanups
+      // for errors, but for now the Sync semantics have been copied...
+      // (one theory is that only cleaning up on error makes it less
+      // likely old error logs would be removed, but that's not true if
+      // there are occasional errors - let's address this later!)
+      if (reason == this.ERROR_LOG_WRITTEN && !this._cleaningUpFileLogs) {
+        this._log.trace("Scheduling cleanup.");
+        // Note we don't return/yield or otherwise wait on this promise - it
+        // continues in the background
+        this.cleanupLogs().catch(err => {
+          this._log.error("Failed to cleanup logs", err);
+        });
+      }
+      return reason;
+    } catch (ex) {
+      this._log.error("Failed to resetFileLog", ex);
+      return null;
+    }
+  }),
+
+  /**
+   * Finds all logs older than maxErrorAge and deletes them using async I/O.
+   */
+  cleanupLogs: Task.async(function* () {
+    this._cleaningUpFileLogs = true;
+    let logDir = FileUtils.getDir("ProfD", this._logFileSubDirectoryEntries);
+    let iterator = new OS.File.DirectoryIterator(logDir.path);
+    let maxAge = this._prefs.get("log.appender.file.maxErrorAge", DEFAULT_MAX_ERROR_AGE);
+    let threshold = Date.now() - 1000 * maxAge;
+
+    this._log.debug("Log cleanup threshold time: " + threshold);
+    yield iterator.forEach(Task.async(function* (entry) {
+      // Note that we don't check this.logFilePrefix is in the name - we cleanup
+      // all files in this directory regardless of that prefix so old logfiles
+      // for prefixes no longer in use are still cleaned up. See bug 1279145.
+      if (!entry.name.startsWith("error-") &&
+          !entry.name.startsWith("success-")) {
+        return;
+      }
+      try {
+        // need to call .stat() as the enumerator doesn't give that to us on *nix.
+        let info = yield OS.File.stat(entry.path);
+        if (info.lastModificationDate.getTime() >= threshold) {
+          return;
+        }
+        this._log.trace(" > Cleanup removing " + entry.name +
+                        " (" + info.lastModificationDate.getTime() + ")");
+        yield OS.File.remove(entry.path);
+        this._log.trace("Deleted " + entry.name);
+      } catch (ex) {
+        this._log.debug("Encountered error trying to clean up old log file "
+                        + entry.name, ex);
+      }
+    }.bind(this)));
+    iterator.close();
+    this._cleaningUpFileLogs = false;
+    this._log.debug("Done deleting files.");
+    // This notification is used only for tests.
+    Services.obs.notifyObservers(null, "services-tests:common:log-manager:cleanup-logs", null);
+  }),
+}