summaryrefslogtreecommitdiffstats
path: root/toolkit/components/telemetry/TelemetryTimestamps.jsm
diff options
context:
space:
mode:
Diffstat (limited to 'toolkit/components/telemetry/TelemetryTimestamps.jsm')
-rw-r--r--toolkit/components/telemetry/TelemetryTimestamps.jsm54
1 files changed, 54 insertions, 0 deletions
diff --git a/toolkit/components/telemetry/TelemetryTimestamps.jsm b/toolkit/components/telemetry/TelemetryTimestamps.jsm
new file mode 100644
index 000000000..e49d7453c
--- /dev/null
+++ b/toolkit/components/telemetry/TelemetryTimestamps.jsm
@@ -0,0 +1,54 @@
+/* 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/. */
+
+this.EXPORTED_SYMBOLS = ["TelemetryTimestamps"];
+
+const Cu = Components.utils;
+
+/**
+ * This module's purpose is to collect timestamps for important
+ * application-specific events.
+ *
+ * The TelemetryController component attaches the timestamps stored by this module to
+ * the telemetry submission, substracting the process lifetime so that the times
+ * are relative to process startup. The overall goal is to produce a basic
+ * timeline of the startup process.
+ */
+var timeStamps = {};
+
+this.TelemetryTimestamps = {
+ /**
+ * Adds a timestamp to the list. The addition of TimeStamps that already have
+ * a value stored is ignored.
+ *
+ * @param name must be a unique, generally "camelCase" descriptor of what the
+ * timestamp represents. e.g.: "delayedStartupStarted"
+ * @param value is a timeStamp in milliseconds since the epoch. If omitted,
+ * defaults to Date.now().
+ */
+ add: function TT_add(name, value) {
+ // Default to "now" if not specified
+ if (value == null)
+ value = Date.now();
+
+ if (isNaN(value))
+ throw new Error("Value must be a timestamp");
+
+ // If there's an existing value, just ignore the new value.
+ if (timeStamps.hasOwnProperty(name))
+ return;
+
+ timeStamps[name] = value;
+ },
+
+ /**
+ * Returns a JS object containing all of the timeStamps as properties (can be
+ * easily serialized to JSON). Used by TelemetryController to retrieve the data
+ * to attach to the telemetry submission.
+ */
+ get: function TT_get() {
+ // Return a copy of the object.
+ return Cu.cloneInto(timeStamps, {});
+ }
+};