gecko-dev/toolkit/modules/ProfileAge.jsm

208 строки
5.9 KiB
JavaScript

/* 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 { Log } = ChromeUtils.import("resource://gre/modules/Log.jsm");
const { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");
const FILE_TIMES = "times.json";
/**
* 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;
log.debug("Iterating over profile " + profilePath);
try {
for (const childPath of await IOUtils.getChildren(profilePath)) {
try {
let info = await IOUtils.stat(childPath);
let timestamp;
if (info.creationTime !== undefined) {
timestamp = info.creationTime;
} else {
// We only support file creation times on Mac and Windows. We have to
// settle for mtime on Linux.
log.debug("No birth date. Using mtime.");
timestamp = info.lastModified;
}
log.debug(`Using date: ${childPath} = ${timestamp}`);
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);
}
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;
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();
}
}
get profilePath() {
if (!this._profilePath) {
this._profilePath = Services.dirsvc.get("ProfD", Ci.nsIFile).path;
}
return this._profilePath;
}
/**
* 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.
*/
async writeTimes() {
try {
await IOUtils.writeJSON(
PathUtils.join(this.profilePath, FILE_TIMES),
this._times
);
} catch (e) {
if (
!(e instanceof DOMException) ||
e.name !== "AbortError" ||
e.message !== "IOUtils: Shutting down and refusing additional I/O tasks"
) {
throw e;
}
}
}
/**
* 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;
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 = PathUtils.join(profile, FILE_TIMES);
try {
let times = await IOUtils.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.
*/
async function ProfileAge(profile) {
if (!profile) {
profile = await PathUtils.getProfileDir();
}
if (PROFILES.has(profile)) {
return PROFILES.get(profile);
}
let promise = initProfileAge(profile);
PROFILES.set(profile, promise);
return promise;
}