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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
const lazy = {};
ChromeUtils.defineESModuleGetters(lazy, {
});
const PREFERENCE_TYPE_MAP = {
boolean: Services.prefs.PREF_BOOL,
string: Services.prefs.PREF_STRING,
number: Services.prefs.PREF_INT,
};
export class PreferenceRolloutAction extends BaseAction {
get schema() {
return lazy.ActionSchemas["preference-rollout"];
}
async _run(recipe) {
const args = recipe.arguments;
// Check if the rollout is on the list of rollouts to stop applying.
if (lazy.PreferenceRollouts.GRADUATION_SET.has(args.slug)) {
this.log.debug(
`Skipping rollout "${args.slug}" because it is in the graduation set.`
);
return;
}
// Determine which preferences are already being managed, to avoid
// conflicts between recipes. This will throw if there is a problem.
await this._verifyRolloutPrefs(args);
const newRollout = {
slug: args.slug,
state: "active",
preferences: args.preferences.map(({ preferenceName, value }) => ({
preferenceName,
value,
previousValue: lazy.PrefUtils.getPref(preferenceName, {
branch: "default",
}),
})),
};
const existingRollout = await lazy.PreferenceRollouts.get(args.slug);
if (existingRollout) {
const anyChanged = await this._updatePrefsForExistingRollout(
existingRollout,
newRollout
);
// If anything was different about the new rollout, write it to the db and send an event about it
if (anyChanged) {
await lazy.PreferenceRollouts.update(newRollout);
lazy.TelemetryEvents.sendEvent(
"update",
"preference_rollout",
args.slug,
{
previousState: existingRollout.state,
}
);
switch (existingRollout.state) {
case lazy.PreferenceRollouts.STATE_ACTIVE: {
this.log.debug(`Updated preference rollout ${args.slug}`);
break;
}
case lazy.PreferenceRollouts.STATE_GRADUATED: {
this.log.debug(`Ungraduated preference rollout ${args.slug}`);
lazy.TelemetryEnvironment.setExperimentActive(
args.slug,
newRollout.state,
{ type: "normandy-prefrollout" }
);
break;
}
default: {
console.error(
new Error(
`Updated pref rollout in unexpected state: ${existingRollout.state}`
)
);
}
}
} else {
this.log.debug(`No updates to preference rollout ${args.slug}`);
}
} else {
// new enrollment
// Check if this rollout would be a no-op, which is not allowed.
if (
newRollout.preferences.every(
({ value, previousValue }) => value === previousValue
)
) {
lazy.TelemetryEvents.sendEvent(
"enrollFailed",
"preference_rollout",
args.slug,
{ reason: "would-be-no-op" }
);
// Throw so that this recipe execution is marked as a failure
throw new Error(
`New rollout ${args.slug} does not change any preferences.`
);
}
await lazy.PreferenceRollouts.add(newRollout);
for (const { preferenceName, value } of args.preferences) {
lazy.PrefUtils.setPref(preferenceName, value, { branch: "default" });
}
this.log.debug(`Enrolled in preference rollout ${args.slug}`);
lazy.TelemetryEnvironment.setExperimentActive(
args.slug,
newRollout.state,
{
type: "normandy-prefrollout",
}
);
lazy.TelemetryEvents.sendEvent(
"enroll",
"preference_rollout",
args.slug,
{}
);
}
}
/**
* Check that all the preferences in a rollout are ok to set. This means 1) no
* other rollout is managing them, and 2) they match the types of the builtin
* values.
* @param {PreferenceRollout} rollout The arguments from a rollout recipe.
* @throws If the preferences are not valid, with details in the error message.
*/
async _verifyRolloutPrefs({ slug, preferences }) {
const existingManagedPrefs = new Set();
for (const rollout of await lazy.PreferenceRollouts.getAllActive()) {
if (rollout.slug === slug) {
continue;
}
for (const prefSpec of rollout.preferences) {
existingManagedPrefs.add(prefSpec.preferenceName);
}
}
for (const prefSpec of preferences) {
if (existingManagedPrefs.has(prefSpec.preferenceName)) {
lazy.TelemetryEvents.sendEvent(
"enrollFailed",
"preference_rollout",
slug,
{
reason: "conflict",
preference: prefSpec.preferenceName,
}
);
// Throw so that this recipe execution is marked as a failure
throw new Error(
`Cannot start rollout ${slug}. Preference ${prefSpec.preferenceName} is already managed.`
);
}
const existingPrefType = Services.prefs.getPrefType(
prefSpec.preferenceName
);
const rolloutPrefType = PREFERENCE_TYPE_MAP[typeof prefSpec.value];
if (
existingPrefType !== Services.prefs.PREF_INVALID &&
existingPrefType !== rolloutPrefType
) {
lazy.TelemetryEvents.sendEvent(
"enrollFailed",
"preference_rollout",
slug,
{
reason: "invalid type",
preference: prefSpec.preferenceName,
}
);
// Throw so that this recipe execution is marked as a failure
throw new Error(
`Cannot start rollout "${slug}" on "${prefSpec.preferenceName}". ` +
`Existing preference is of type ${existingPrefType}, but rollout ` +
`specifies type ${rolloutPrefType}`
);
}
}
}
async _updatePrefsForExistingRollout(existingRollout, newRollout) {
let anyChanged = false;
const oldPrefSpecs = new Map(
existingRollout.preferences.map(p => [p.preferenceName, p])
);
const newPrefSpecs = new Map(
newRollout.preferences.map(p => [p.preferenceName, p])
);
// Check for any preferences that no longer exist, and un-set them.
for (const { preferenceName, previousValue } of oldPrefSpecs.values()) {
if (!newPrefSpecs.has(preferenceName)) {
this.log.debug(
`updating ${existingRollout.slug}: ${preferenceName} no longer exists`
);
anyChanged = true;
lazy.PrefUtils.setPref(preferenceName, previousValue, {
branch: "default",
});
}
}
// Check for any preferences that are new and need added, or changed and need updated.
for (const prefSpec of Object.values(newRollout.preferences)) {
let oldValue = null;
if (oldPrefSpecs.has(prefSpec.preferenceName)) {
let oldPrefSpec = oldPrefSpecs.get(prefSpec.preferenceName);
oldValue = oldPrefSpec.value;
// Trust the old rollout for the values of `previousValue`, but don't
// consider this a change, since it already matches the DB, and doesn't
// have any other stateful effect.
prefSpec.previousValue = oldPrefSpec.previousValue;
}
if (oldValue !== newPrefSpecs.get(prefSpec.preferenceName).value) {
anyChanged = true;
this.log.debug(
`updating ${existingRollout.slug}: ${prefSpec.preferenceName} value changed from ${oldValue} to ${prefSpec.value}`
);
lazy.PrefUtils.setPref(prefSpec.preferenceName, prefSpec.value, {
branch: "default",
});
}
}
return anyChanged;
}
async _finalize() {
await lazy.PreferenceRollouts.saveStartupPrefs();
}
}