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/* 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 = ["ProfileAge"];
const { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");
const { TelemetryUtils } = ChromeUtils.import(
);
const { OS } = ChromeUtils.import("resource://gre/modules/osfile.jsm");
const { Log } = ChromeUtils.import("resource://gre/modules/Log.jsm");
const { CommonUtils } = ChromeUtils.import(
);
const FILE_TIMES = "times.json";
/**
* Calculate how many days passed between two dates.
* @param {Object} aStartDate The starting date.
* @param {Object} aEndDate The ending date.
* @return {Integer} The number of days between the two dates.
*/
function getElapsedTimeInDays(aStartDate, aEndDate) {
return TelemetryUtils.millisecondsToDays(aEndDate - aStartDate);
}
/**
* Traverse the contents of the profile directory, finding the oldest file
* and returning its creation timestamp.
*/
async function getOldestProfileTimestamp(profilePath, log) {
let start = Date.now();
let oldest = start + 1000;
let iterator = new OS.File.DirectoryIterator(profilePath);
log.debug("Iterating over profile " + profilePath);
if (!iterator) {
throw new Error(
"Unable to fetch oldest profile entry: no profile iterator."
);
}
Services.telemetry.scalarAdd("telemetry.profile_directory_scans", 1);
let histogram = Services.telemetry.getHistogramById(
"PROFILE_DIRECTORY_FILE_AGE"
);
try {
await iterator.forEach(async entry => {
try {
let info = await OS.File.stat(entry.path);
// OS.File doesn't seem to be behaving. See Bug 827148.
// Let's do the best we can. This whole function is defensive.
let date = info.winBirthDate || info.macBirthDate;
if (!date || !date.getTime()) {
// OS.File will only return file creation times of any kind on Mac
// and Windows, where birthTime is defined.
// That means we're unable to function on Linux, so we use mtime
// instead.
log.debug("No birth date. Using mtime.");
date = info.lastModificationDate;
}
if (date) {
let timestamp = date.getTime();
// Get the age relative to now.
// We don't care about dates in the future.
let age_in_days = Math.max(0, getElapsedTimeInDays(timestamp, start));
histogram.add(age_in_days);
log.debug("Using date: " + entry.path + " = " + date);
if (timestamp < oldest) {
oldest = timestamp;
}
}
} catch (e) {
// Never mind.
log.debug("Stat failure", e);
}
});
} catch (reason) {
throw new Error("Unable to fetch oldest profile entry: " + reason);
} finally {
iterator.close();
}
return oldest;
}
/**
* Profile access to times.json (eg, creation/reset time).
* This is separate from the provider to simplify testing and enable extraction
* to a shared location in the future.
*/
class ProfileAgeImpl {
constructor(profile, times) {
this.profilePath = profile || OS.Constants.Path.profileDir;
this._times = times;
this._log = Log.repository.getLogger("Toolkit.ProfileAge");
if ("firstUse" in this._times && this._times.firstUse === null) {
// Indicates that this is a new profile that needs a first use timestamp.
this._times.firstUse = Date.now();
this.writeTimes();
}
}
/**
* There are two ways we can get our creation time:
*
* 1. From the on-disk JSON file.
* 2. By calculating it from the filesystem.
*
* If we have to calculate, we write out the file; if we have
* to touch the file, we persist in-memory.
*
* @return a promise that resolves to the profile's creation time.
*/
get created() {
// This can be an expensive operation so make sure we only do it once.
if (this._created) {
return this._created;
}
if (!this._times.created) {
this._created = this.computeAndPersistCreated();
} else {
this._created = Promise.resolve(this._times.created);
}
return this._created;
}
/**
* Returns a promise to the time of first use of the profile. This may be
* undefined if the first use time is unknown.
*/
get firstUse() {
if ("firstUse" in this._times) {
return Promise.resolve(this._times.firstUse);
}
return Promise.resolve(undefined);
}
/**
* Return a promise representing the writing the current times to the profile.
*/
writeTimes() {
return CommonUtils.writeJSON(
this._times,
OS.Path.join(this.profilePath, FILE_TIMES)
);
}
/**
* Calculates the created time by scanning the profile directory, sets it in
* the current set of times and persists it to the profile. Returns a promise
* that resolves when all of that is complete.
*/
async computeAndPersistCreated() {
let oldest = await getOldestProfileTimestamp(this.profilePath, this._log);
this._times.created = oldest;
Services.telemetry.scalarSet(
"telemetry.profile_directory_scan_date",
TelemetryUtils.millisecondsToDays(Date.now())
);
await this.writeTimes();
return oldest;
}
/**
* Record (and persist) when a profile reset happened. We just store a
* single value - the timestamp of the most recent reset - but there is scope
* to keep a list of reset times should our health-reporter successor
* be able to make use of that.
* Returns a promise that is resolved once the file has been written.
*/
recordProfileReset(time = Date.now()) {
this._times.reset = time;
return this.writeTimes();
}
/* Returns a promise that resolves to the time the profile was reset,
* or undefined if not recorded.
*/
get reset() {
if ("reset" in this._times) {
return Promise.resolve(this._times.reset);
}
return Promise.resolve(undefined);
}
}
// A Map from profile directory to a promise that resolves to the ProfileAgeImpl.
const PROFILES = new Map();
async function initProfileAge(profile) {
let timesPath = OS.Path.join(profile, FILE_TIMES);
try {
let times = await CommonUtils.readJSON(timesPath);
return new ProfileAgeImpl(profile, times || {});
} catch (e) {
// Indicates that the file was missing or broken. In this case we want to
// record the first use time as now. The constructor will set this and write
// times.json
return new ProfileAgeImpl(profile, { firstUse: null });
}
}
/**
* Returns a promise that resolves to an instance of ProfileAgeImpl. Will always
* return the same instance for every call for the same profile.
*
* @param {string} profile The path to the profile directory.
* @return {Promise<ProfileAgeImpl>} Resolves to the ProfileAgeImpl.
*/
function ProfileAge(profile = OS.Constants.Path.profileDir) {
if (PROFILES.has(profile)) {
return PROFILES.get(profile);
}
let promise = initProfileAge(profile);
PROFILES.set(profile, promise);
return promise;
}