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/* vim: set ts=2 sw=2 sts=2 et tw=80: */
/* 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 = {};
import { XPCOMUtils } from "resource://gre/modules/XPCOMUtils.sys.mjs";
import { AppConstants } from "resource://gre/modules/AppConstants.sys.mjs";
ChromeUtils.defineESModuleGetters(lazy, {
IndexedDB: "resource://gre/modules/IndexedDB.sys.mjs",
DAPTelemetrySender: "resource://gre/modules/DAPTelemetrySender.sys.mjs",
HPKEConfigManager: "resource://gre/modules/HPKEConfigManager.sys.mjs",
setTimeout: "resource://gre/modules/Timer.sys.mjs",
});
XPCOMUtils.defineLazyPreferenceGetter(
lazy,
"gIsTelemetrySendingEnabled",
"datareporting.healthreport.uploadEnabled",
true
);
XPCOMUtils.defineLazyPreferenceGetter(
lazy,
"gIsPPAEnabled",
"dom.private-attribution.submission.enabled",
true
);
XPCOMUtils.defineLazyPreferenceGetter(
lazy,
"gOhttpRelayUrl",
"toolkit.shopping.ohttpRelayURL"
);
XPCOMUtils.defineLazyPreferenceGetter(
lazy,
"gOhttpGatewayKeyUrl",
"toolkit.shopping.ohttpConfigURL"
);
const MAX_CONVERSIONS = 2;
const DAY_IN_MILLI = 1000 * 60 * 60 * 24;
const CONVERSION_RESET_MILLI = 7 * DAY_IN_MILLI;
const DAP_TIMEOUT_MILLI = 30000;
/**
*
*/
export class PrivateAttributionService {
constructor({
dapTelemetrySender,
dateProvider,
testForceEnabled,
testDapOptions,
} = {}) {
this._dapTelemetrySender = dapTelemetrySender;
this._dateProvider = dateProvider ?? Date;
this._testForceEnabled = testForceEnabled;
this._testDapOptions = testDapOptions;
this.dbName = "PrivateAttribution";
this.impressionStoreName = "impressions";
this.budgetStoreName = "budgets";
this.storeNames = [this.impressionStoreName, this.budgetStoreName];
this.dbVersion = 1;
this.models = {
default: "lastImpression",
view: "lastView",
click: "lastClick",
};
}
get dapTelemetrySender() {
return this._dapTelemetrySender || lazy.DAPTelemetrySender;
}
now() {
return this._dateProvider.now();
}
async onAttributionEvent(sourceHost, type, index, ad, targetHost) {
if (!this.isEnabled()) {
return;
}
const now = this.now();
try {
const impressionStore = await this.getImpressionStore();
const impression = await this.getImpression(impressionStore, ad, {
index,
target: targetHost,
source: sourceHost,
});
const prop = this.getModelProp(type);
impression.index = index;
impression.lastImpression = now;
impression[prop] = now;
await this.updateImpression(impressionStore, ad, impression);
} catch (e) {
console.error(e);
}
}
async onAttributionConversion(
targetHost,
task,
histogramSize,
lookbackDays,
impressionType,
ads,
sourceHosts
) {
if (!this.isEnabled()) {
return;
}
const now = this.now();
try {
const budget = await this.getBudget(targetHost, now);
const impression = await this.findImpression(
ads,
targetHost,
sourceHosts,
impressionType,
lookbackDays,
histogramSize,
now
);
let index = 0;
let value = 0;
if (budget.conversions < MAX_CONVERSIONS && impression) {
index = impression.index;
value = 1;
}
await this.updateBudget(budget, value, targetHost);
await this.sendDapReport(task, index, histogramSize, value);
} catch (e) {
console.error(e);
}
}
async findImpression(ads, target, sources, model, days, histogramSize, now) {
let impressions = [];
const impressionStore = await this.getImpressionStore();
// Get matching ad impressions
if (ads && ads.length) {
for (var i = 0; i < ads.length; i++) {
impressions = impressions.concat(
(await impressionStore.get(ads[i])) ?? []
);
}
} else {
impressions = (await impressionStore.getAll()).flat(1);
}
// Set attribution model properties
const prop = this.getModelProp(model);
// Find the most relevant impression
const lookbackWindow = now - days * DAY_IN_MILLI;
return (
impressions
// Filter by target, sources, and lookback days
.filter(
impression =>
impression.target === target &&
(!sources || sources.includes(impression.source)) &&
impression[prop] >= lookbackWindow &&
impression.index < histogramSize
)
// Get the impression with the most recent interaction
.reduce(
(cur, impression) =>
!cur || impression[prop] > cur[prop] ? impression : cur,
null
)
);
}
async getImpression(impressionStore, ad, defaultImpression) {
const impressions = (await impressionStore.get(ad)) ?? [];
const impression = impressions.find(r =>
this.compareImpression(r, defaultImpression)
);
return impression ?? defaultImpression;
}
async updateImpression(impressionStore, key, impression) {
let impressions = (await impressionStore.get(key)) ?? [];
const i = impressions.findIndex(r => this.compareImpression(r, impression));
if (i < 0) {
impressions.push(impression);
} else {
impressions[i] = impression;
}
await impressionStore.put(impressions, key);
}
compareImpression(cur, impression) {
return cur.source === impression.source && cur.target === impression.target;
}
async getBudget(target, now) {
const budgetStore = await this.getBudgetStore();
const budget = await budgetStore.get(target);
if (!budget || now > budget.nextReset) {
return {
conversions: 0,
nextReset: now + CONVERSION_RESET_MILLI,
};
}
return budget;
}
async updateBudget(budget, value, target) {
const budgetStore = await this.getBudgetStore();
budget.conversions += value;
await budgetStore.put(budget, target);
}
async getImpressionStore() {
return await this.getStore(this.impressionStoreName);
}
async getBudgetStore() {
return await this.getStore(this.budgetStoreName);
}
async getStore(storeName) {
return (await this.db).objectStore(storeName, "readwrite");
}
get db() {
return this._db || (this._db = this.createOrOpenDb());
}
async createOrOpenDb() {
try {
return await this.openDatabase();
} catch {
await lazy.IndexedDB.deleteDatabase(this.dbName);
return this.openDatabase();
}
}
async openDatabase() {
return await lazy.IndexedDB.open(this.dbName, this.dbVersion, db => {
this.storeNames.forEach(store => {
if (!db.objectStoreNames.contains(store)) {
db.createObjectStore(store);
}
});
});
}
async sendDapReport(id, index, size, value) {
const task = {
id,
vdaf: "sumvec",
bits: 8,
length: size,
time_precision: 60,
};
const measurement = new Array(size).fill(0);
measurement[index] = value;
let options = {
timeout: DAP_TIMEOUT_MILLI,
ohttp_relay: lazy.gOhttpRelayUrl,
...this._testDapOptions,
};
if (options.ohttp_relay) {
// Fetch the OHTTP-Gateway-HPKE key if not provided yet.
if (!options.ohttp_hpke) {
const controller = new AbortController();
lazy.setTimeout(() => controller.abort(), DAP_TIMEOUT_MILLI);
options.ohttp_hpke = await lazy.HPKEConfigManager.get(
lazy.gOhttpGatewayKeyUrl,
{
maxAge: DAY_IN_MILLI,
abortSignal: controller.signal,
}
);
}
} else if (!this._testForceEnabled) {
// Except for testing, do no allow PPA to bypass OHTTP.
throw new Error("PPA requires an OHTTP relay for submission");
}
await this.dapTelemetrySender.sendDAPMeasurement(
task,
measurement,
options
);
}
getModelProp(type) {
return this.models[type ? type : "default"];
}
isEnabled() {
return (
this._testForceEnabled ||
(lazy.gIsTelemetrySendingEnabled &&
AppConstants.MOZ_TELEMETRY_REPORTING &&
lazy.gIsPPAEnabled)
);
}
QueryInterface = ChromeUtils.generateQI([Ci.nsIPrivateAttributionService]);
}