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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
/**
* @typedef {Object} Study
* @property {Number} recipeId
* ID of the recipe that created the study. Used as the primary key of the
* study.
* @property {Number} slug
* String code used to identify the study for use in Telemetry and logging.
* @property {string} userFacingName
* Name of the study to show to the user
* @property {string} userFacingDescription
* Description of the study and its intent.
* @property {string} branch
* The branch the user is enrolled in
* @property {boolean} active
* Is the study still running?
* @property {string} addonId
* Add-on ID for this particular study.
* @property {string} addonUrl
* URL that the study add-on was installed from.
* @property {string} addonVersion
* Study add-on version number
* @property {int} extensionApiId
* The ID used to look up the extension in Normandy's API.
* @property {string} extensionHash
* The hash of the XPI file.
* @property {string} extensionHashAlgorithm
* The algorithm used to hash the XPI file.
* @property {Date} studyStartDate
* Date when the study was started.
* @property {Date|null} studyEndDate
* Date when the study was ended.
* @property {Date|null} temporaryErrorDeadline
* Date of when temporary errors with this experiment should no longer be
* considered temporary. After this point, further errors will result in
* unenrollment.
*/
const lazy = {};
ChromeUtils.defineESModuleGetters(lazy, {
BranchedAddonStudyAction:
});
const DB_NAME = "shield";
const STORE_NAME = "addon-studies";
const VERSION_STORE_NAME = "addon-studies-version";
const DB_VERSION = 2;
const STUDY_ENDED_TOPIC = "shield-study-ended";
const log = LogManager.getLogger("addon-studies");
/**
* Create a new connection to the database.
*/
function openDatabase() {
return lazy.IndexedDB.open(DB_NAME, DB_VERSION, async (db, event) => {
if (event.oldVersion < 1) {
db.createObjectStore(STORE_NAME, {
keyPath: "recipeId",
});
}
if (event.oldVersion < 2) {
db.createObjectStore(VERSION_STORE_NAME);
}
});
}
/**
* Cache the database connection so that it is shared among multiple operations.
*/
let databasePromise;
async function getDatabase() {
if (!databasePromise) {
databasePromise = openDatabase();
}
return databasePromise;
}
/**
* Get a transaction for interacting with the study store.
*
* @param {IDBDatabase} db
* @param {String} mode Either "readonly" or "readwrite"
*
* NOTE: Methods on the store returned by this function MUST be called
* synchronously, otherwise the transaction with the store will expire.
* This is why the helper takes a database as an argument; if we fetched the
* database in the helper directly, the helper would be async and the
* transaction would expire before methods on the store were called.
*/
function getStore(db, mode) {
if (!mode) {
throw new Error("mode is required");
}
return db.objectStore(STORE_NAME, mode);
}
export var AddonStudies = {
/**
* Test wrapper that temporarily replaces the stored studies with the given
* ones. The original stored studies are restored upon completion.
*
* This is defined here instead of in test code since it needs to access the
* getDatabase, which we don't expose to avoid outside modules relying on the
* type of storage used for studies.
*
* @param {Array} [addonStudies=[]]
*/
withStudies(addonStudies = []) {
return function wrapper(testFunction) {
return async function wrappedTestFunction(args) {
const oldStudies = await AddonStudies.getAll();
let db = await getDatabase();
await AddonStudies.clear();
const store = getStore(db, "readwrite");
await Promise.all(addonStudies.map(study => store.add(study)));
try {
await testFunction({ ...args, addonStudies });
} finally {
db = await getDatabase();
await AddonStudies.clear();
const store = getStore(db, "readwrite");
await Promise.all(oldStudies.map(study => store.add(study)));
}
};
};
},
async init() {
for (const study of await this.getAllActive()) {
// If an active study's add-on has been removed since we last ran, stop it.
const addon = await lazy.AddonManager.getAddonByID(study.addonId);
if (!addon) {
await this.markAsEnded(study, "uninstalled-sideload");
continue;
}
// Otherwise mark that study as active in Telemetry
lazy.TelemetryEnvironment.setExperimentActive(study.slug, study.branch, {
type: "normandy-addonstudy",
});
}
// Listen for add-on uninstalls so we can stop the corresponding studies.
lazy.AddonManager.addAddonListener(this);
lazy.CleanupManager.addCleanupHandler(() => {
lazy.AddonManager.removeAddonListener(this);
});
},
/**
* These migrations should only be called from `NormandyMigrations.sys.mjs` and
* tests.
*/
migrations: {
/**
* Change from "name" and "description" to "slug", "userFacingName",
* and "userFacingDescription".
*/
async migration01AddonStudyFieldsToSlugAndUserFacingFields() {
const db = await getDatabase();
const studies = await db.objectStore(STORE_NAME, "readonly").getAll();
// If there are no studies, stop here to avoid opening the DB again.
if (studies.length === 0) {
return;
}
// Object stores expire after `await`, so this method accumulates a bunch of
// promises, and then awaits them at the end.
const writePromises = [];
const objectStore = db.objectStore(STORE_NAME, "readwrite");
for (const study of studies) {
// use existing name as slug
if (!study.slug) {
study.slug = study.name;
}
// Rename `name` and `description` as `userFacingName` and `userFacingDescription`
if (study.name && !study.userFacingName) {
study.userFacingName = study.name;
}
delete study.name;
if (study.description && !study.userFacingDescription) {
study.userFacingDescription = study.description;
}
delete study.description;
// Specify that existing recipes don't have branches
if (!study.branch) {
study.branch = AddonStudies.NO_BRANCHES_MARKER;
}
writePromises.push(objectStore.put(study));
}
await Promise.all(writePromises);
},
async migration02RemoveOldAddonStudyAction() {
const studies = await AddonStudies.getAllActive({
branched: AddonStudies.FILTER_NOT_BRANCHED,
});
if (!studies.length) {
return;
}
const action = new lazy.BranchedAddonStudyAction();
for (const study of studies) {
try {
await action.unenroll(
study.recipeId,
"migration-removing-unbranched-action"
);
} catch (e) {
log.error(
`Stopping add-on study ${study.slug} during migration failed: ${e}`
);
}
}
},
},
/**
* If a study add-on is uninstalled, mark the study as having ended.
* @param {Addon} addon
*/
async onUninstalled(addon) {
const activeStudies = (await this.getAll()).filter(study => study.active);
const matchingStudy = activeStudies.find(
study => study.addonId === addon.id
);
if (matchingStudy) {
await this.markAsEnded(matchingStudy, "uninstalled");
}
},
/**
* Remove all stored studies.
*/
async clear() {
const db = await getDatabase();
await getStore(db, "readwrite").clear();
},
/**
* Test whether there is a study in storage for the given recipe ID.
* @param {Number} recipeId
* @returns {Boolean}
*/
async has(recipeId) {
const db = await getDatabase();
const study = await getStore(db, "readonly").get(recipeId);
return !!study;
},
/**
* Fetch a study from storage.
* @param {Number} recipeId
* @return {Study} The requested study, or null if none with that ID exist.
*/
async get(recipeId) {
const db = await getDatabase();
return getStore(db, "readonly").get(recipeId);
},
FILTER_BRANCHED_ONLY: Symbol("FILTER_BRANCHED_ONLY"),
FILTER_NOT_BRANCHED: Symbol("FILTER_NOT_BRANCHED"),
FILTER_ALL: Symbol("FILTER_ALL"),
/**
* Fetch all studies in storage.
* @return {Array<Study>}
*/
async getAll({ branched = AddonStudies.FILTER_ALL } = {}) {
const db = await getDatabase();
let results = await getStore(db, "readonly").getAll();
if (branched == AddonStudies.FILTER_BRANCHED_ONLY) {
results = results.filter(
study => study.branch != AddonStudies.NO_BRANCHES_MARKER
);
} else if (branched == AddonStudies.FILTER_NOT_BRANCHED) {
results = results.filter(
study => study.branch == AddonStudies.NO_BRANCHES_MARKER
);
}
return results;
},
/**
* Fetch all studies in storage.
* @return {Array<Study>}
*/
async getAllActive(options) {
return (await this.getAll(options)).filter(study => study.active);
},
/**
* Add a study to storage.
* @return {Promise<void, Error>} Resolves when the study is stored, or rejects with an error.
*/
async add(study) {
const db = await getDatabase();
return getStore(db, "readwrite").add(study);
},
/**
* Update a study in storage.
* @return {Promise<void, Error>} Resolves when the study is updated, or rejects with an error.
*/
async update(study) {
const db = await getDatabase();
return getStore(db, "readwrite").put(study);
},
/**
* Update many existing studies. More efficient than calling `update` many
* times in a row.
* @param {Array<AddonStudy>} studies
* @throws If any of the passed studies have a slug that doesn't exist in the database already.
*/
async updateMany(studies) {
// Don't touch the database if there is nothing to do
if (!studies.length) {
return;
}
// Both of the below operations use .map() instead of a normal loop becaues
// once we get the object store, we can't let it expire by spinning the
// event loop. This approach queues up all the interactions with the store
// immediately, preventing it from expiring too soon.
const db = await getDatabase();
let store = await getStore(db, "readonly");
await Promise.all(
studies.map(async ({ recipeId }) => {
let existingStudy = await store.get(recipeId);
if (!existingStudy) {
throw new Error(
`Tried to update addon study ${recipeId}, but it doesn't exist.`
);
}
})
);
// awaiting spun the event loop, so the store is now invalid. Get a new
// store. This is also a chance to get it in readwrite mode.
store = await getStore(db, "readwrite");
await Promise.all(studies.map(study => store.put(study)));
},
/**
* Remove a study from storage
* @param recipeId The recipeId of the study to delete
* @return {Promise<void, Error>} Resolves when the study is deleted, or rejects with an error.
*/
async delete(recipeId) {
const db = await getDatabase();
return getStore(db, "readwrite").delete(recipeId);
},
/**
* Mark a study object as having ended. Modifies the study in-place.
* @param {IDBDatabase} db
* @param {Study} study
* @param {String} reason Why the study is ending.
*/
async markAsEnded(study, reason = "unknown") {
if (reason === "unknown") {
log.warn(`Study ${study.slug} ending for unknown reason.`);
}
study.active = false;
study.temporaryErrorDeadline = null;
study.studyEndDate = new Date();
const db = await getDatabase();
await getStore(db, "readwrite").put(study);
Services.obs.notifyObservers(study, STUDY_ENDED_TOPIC, `${study.recipeId}`);
lazy.TelemetryEvents.sendEvent("unenroll", "addon_study", study.slug, {
addonId: study.addonId || AddonStudies.NO_ADDON_MARKER,
addonVersion: study.addonVersion || AddonStudies.NO_ADDON_MARKER,
reason,
branch: study.branch,
});
lazy.TelemetryEnvironment.setExperimentInactive(study.slug);
await this.callUnenrollListeners(study.addonId, reason);
},
// Maps extension id -> Set(callbacks)
_unenrollListeners: new Map(),
/**
* Register a callback to be invoked when a given study ends.
*
* @param {string} id The extension id
* @param {function} listener The callback
*/
addUnenrollListener(id, listener) {
let listeners = this._unenrollListeners.get(id);
if (!listeners) {
listeners = new Set();
this._unenrollListeners.set(id, listeners);
}
listeners.add(listener);
},
/**
* Unregister a callback to be invoked when a given study ends.
*
* @param {string} id The extension id
* @param {function} listener The callback
*/
removeUnenrollListener(id, listener) {
let listeners = this._unenrollListeners.get(id);
if (listeners) {
listeners.delete(listener);
}
},
/**
* Invoke the unenroll callback (if any) for the given extension
*
* @param {string} id The extension id
* @param {string} reason Why the study is ending
*
* @returns {Promise} A Promise resolved after the unenroll listener
* (if any) has finished its unenroll tasks.
*/
async callUnenrollListeners(id, reason) {
let callbacks = this._unenrollListeners.get(id) || [];
async function callCallback(cb, reason) {
try {
await cb(reason);
} catch (err) {
console.error(err);
}
}
let promises = [];
for (let callback of callbacks) {
promises.push(callCallback(callback, reason));
}
// Wait for all the promises to be settled. This won't throw even if some of
// the listeners fail.
await Promise.all(promises);
},
};
AddonStudies.NO_BRANCHES_MARKER = "__NO_BRANCHES__";
AddonStudies.NO_ADDON_MARKER = "__NO_ADDON__";