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amp-a4a.js
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amp-a4a.js
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/**
* Copyright 2016 The AMP HTML Authors. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS-IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import {Services} from '../../../src/services';
import {SignatureVerifier, VerificationStatus} from './signature-verifier';
import {
is3pThrottled,
getAmpAdRenderOutsideViewport,
incrementLoadingAds,
} from '../../amp-ad/0.1/concurrent-load';
import {createElementWithAttributes} from '../../../src/dom';
import {cancellation, isCancellation} from '../../../src/error';
import {
installFriendlyIframeEmbed,
setFriendlyIframeEmbedVisible,
} from '../../../src/friendly-iframe-embed';
import {isLayoutSizeDefined, Layout} from '../../../src/layout';
import {isAdPositionAllowed} from '../../../src/ad-helper';
import {dev, user, duplicateErrorIfNecessary} from '../../../src/log';
import {dict} from '../../../src/utils/object';
import {getMode} from '../../../src/mode';
import {isArray, isObject, isEnumValue} from '../../../src/types';
import {utf8Decode} from '../../../src/utils/bytes';
import {getBinaryType, isExperimentOn} from '../../../src/experiments';
import {setStyle} from '../../../src/style';
import {
assertHttpsUrl,
isSecureUrl,
tryDecodeUriComponent,
} from '../../../src/url';
import {parseJson} from '../../../src/json';
import {handleClick} from '../../../ads/alp/handler';
import {
getDefaultBootstrapBaseUrl,
generateSentinel,
} from '../../../src/3p-frame';
import {
installUrlReplacementsForEmbed,
} from '../../../src/service/url-replacements-impl';
import {A4AVariableSource} from './a4a-variable-source';
// TODO(tdrl): Temporary. Remove when we migrate to using amp-analytics.
import {getTimingDataAsync} from '../../../src/service/variable-source';
import {getContextMetadata} from '../../../src/iframe-attributes';
import {getBinaryTypeNumericalCode} from '../../../ads/google/a4a/utils';
import {signingServerURLs} from '../../../ads/_a4a-config';
import {triggerAnalyticsEvent} from '../../../src/analytics';
import {insertAnalyticsElement} from '../../../src/extension-analytics';
/** @type {Array<string>} */
const METADATA_STRINGS = [
'<script amp-ad-metadata type=application/json>',
'<script type="application/json" amp-ad-metadata>',
'<script type=application/json amp-ad-metadata>'];
// TODO(tdrl): Temporary, while we're verifying whether SafeFrame is an
// acceptable solution to the 'Safari on iOS doesn't fetch iframe src from
// cache' issue. See https://github.com/ampproject/amphtml/issues/5614
/** @type {string} */
export const DEFAULT_SAFEFRAME_VERSION = '1-0-14';
/** @const {string} */
export const CREATIVE_SIZE_HEADER = 'X-CreativeSize';
/** @type {string} @visibleForTesting */
export const RENDERING_TYPE_HEADER = 'X-AmpAdRender';
/** @type {string} @visibleForTesting */
export const SAFEFRAME_VERSION_HEADER = 'X-AmpSafeFrameVersion';
/** @type {string} @visibleForTesting */
export const EXPERIMENT_FEATURE_HEADER_NAME = 'amp-ff-exps';
/** @type {string} */
const TAG = 'amp-a4a';
/** @type {string} */
export const NO_CONTENT_RESPONSE = 'NO-CONTENT-RESPONSE';
/** @enum {string} */
export const XORIGIN_MODE = {
CLIENT_CACHE: 'client_cache',
SAFEFRAME: 'safeframe',
NAMEFRAME: 'nameframe',
};
/** @type {!Object} @private */
const SHARED_IFRAME_PROPERTIES = dict({
'frameborder': '0',
'allowfullscreen': '',
'allowtransparency': '',
'scrolling': 'no',
'marginwidth': '0',
'marginheight': '0',
});
/** @typedef {{width: number, height: number}} */
export let SizeInfoDef;
/** @typedef {{
minifiedCreative: string,
customElementExtensions: !Array<string>,
customStylesheets: !Array<{href: string}>,
images: (Array<string>|undefined),
}} */
export let CreativeMetaDataDef;
/** @private */
export const LIFECYCLE_STAGES = {
// Note: Use strings as values here, rather than numbers, so that "0" does
// not test as `false` later.
adSlotCleared: '-1',
urlBuilt: '1',
adRequestStart: '2',
adRequestEnd: '3',
adResponseValidateStart: '5',
renderFriendlyStart: '6', // TODO(dvoytenko): this signal and similar are actually "embed-create", not "render-start".
renderCrossDomainStart: '7',
renderFriendlyEnd: '8',
renderCrossDomainEnd: '9',
preAdThrottle: '10',
renderSafeFrameStart: '11',
throttled3p: '12',
adResponseValidateEnd: '13',
xDomIframeLoaded: '14',
friendlyIframeLoaded: '15',
adSlotCollapsed: '16',
adSlotUnhidden: '17',
layoutAdPromiseDelay: '18',
signatureVerifySuccess: '19',
networkError: '20',
friendlyIframeIniLoad: '21',
visHalf: '22',
visHalfIniLoad: '23',
firstVisible: '24',
visLoadAndOneSec: '25',
iniLoad: '26',
resumeCallback: '27',
visIniLoad: '29',
upgradeDelay: '30',
// TODO(warrengm): This should replace xDomIframeLoaded once delayed fetch
// is fully deprecated. A new lifecycle stage, crossDomainIframeLoaded, was
// introduced since xDomIframeLoaded is handled in AmpAdXOriginIframeHandler
// outside A4A.
crossDomainIframeLoaded: '31',
};
/**
* Name of A4A lifecycle triggers.
* @enum {string}
*/
export const AnalyticsTrigger = {
AD_REQUEST_START: 'ad-request-start',
AD_RESPONSE_END: 'ad-response-end',
AD_RENDER_START: 'ad-render-start',
AD_RENDER_END: 'ad-render-end',
AD_IFRAME_LOADED: 'ad-iframe-loaded',
};
/**
* Maps the names of lifecycle events to analytics triggers.
* @const {!Object<string, !AnalyticsTrigger>}
*/
const LIFECYCLE_STAGE_TO_ANALYTICS_TRIGGER = {
'adRequestStart': AnalyticsTrigger.AD_REQUEST_START,
'adRequestEnd': AnalyticsTrigger.AD_RESPONSE_END,
'renderFriendlyStart': AnalyticsTrigger.AD_RENDER_START,
'renderCrossDomainStart': AnalyticsTrigger.AD_RENDER_START,
'renderSafeFrameStart': AnalyticsTrigger.AD_RENDER_START,
'renderFriendlyEnd': AnalyticsTrigger.AD_RENDER_END,
'renderCrossDomainEnd': AnalyticsTrigger.AD_RENDER_END,
'friendlyIframeIniLoad': AnalyticsTrigger.AD_IFRAME_LOADED,
'crossDomainIframeLoaded': AnalyticsTrigger.AD_IFRAME_LOADED,
};
/**
* Utility function that ensures any error thrown is handled by optional
* onError handler (if none provided or handler throws, error is swallowed and
* undefined is returned).
* @param {!Function} fn to protect
* @param {T=} inThis An optional object to use as the 'this' object
* when calling the function. If not provided, undefined is bound as this
* when calling function.
* @param {function(this:T, !Error, ...*):?=} onError function given error
* and arguments provided to function call.
* @return {!Function} protected function
* @template T
* @visibleForTesting
*/
export function protectFunctionWrapper(
fn, inThis = undefined, onError = undefined) {
return (...fnArgs) => {
try {
return fn.apply(inThis, fnArgs);
} catch (err) {
if (onError) {
try {
// Ideally we could use [err, ...var_args] but linter disallows
// spread so instead using unshift :(
fnArgs.unshift(err);
return onError.apply(inThis, fnArgs);
} catch (captureErr) {
// swallow error if error handler throws.
}
}
// In the event of no optional on error function or its execution throws,
// return undefined.
return undefined;
}
};
};
export class AmpA4A extends AMP.BaseElement {
// TODO: Add more error handling throughout code.
// TODO: Handle creatives that do not fill.
/**
* @param {!Element} element
*/
constructor(element) {
super(element);
dev().assert(AMP.AmpAdUIHandler);
dev().assert(AMP.AmpAdXOriginIframeHandler);
/** @private {?Promise<undefined>} */
this.keysetPromise_ = null;
/** @private {?Promise<?CreativeMetaDataDef>} */
this.adPromise_ = null;
/**
* @private {number} unique ID of the currently executing promise to allow
* for cancellation.
*/
this.promiseId_ = 0;
/** @private {?string} */
this.adUrl_ = null;
/** @private {?../../../src/friendly-iframe-embed.FriendlyIframeEmbed} */
this.friendlyIframeEmbed_ = null;
/** {?AMP.AmpAdUIHandler} */
this.uiHandler = null;
/** @private {?AMP.AmpAdXOriginIframeHandler} */
this.xOriginIframeHandler_ = null;
/** @private {boolean} whether creative has been verified as AMP */
this.isVerifiedAmpCreative_ = false;
/** @private {?ArrayBuffer} */
this.creativeBody_ = null;
/**
* Initialize this with the slot width/height attributes, and override
* later with what the network implementation returns via extractSize.
* Note: Either value may be 'auto' (i.e., non-numeric).
*
* @private {?({width, height}|../../../src/layout-rect.LayoutRectDef)}
*/
this.creativeSize_ = null;
/** @private {?../../../src/layout-rect.LayoutRectDef} */
this.originalSlotSize_ = null;
/**
* Note(keithwrightbos) - ensure the default here is null so that ios
* uses safeframe when response header is not specified.
* @private {?XORIGIN_MODE}
*/
this.experimentalNonAmpCreativeRenderMethod_ =
this.getNonAmpCreativeRenderingMethod();
/**
* Gets a notion of current time, in ms. The value is not necessarily
* absolute, so should be used only for computing deltas. When available,
* the performance system will be used; otherwise Date.now() will be
* returned.
*
* @const {function():number}
*/
this.getNow_ = (this.win.performance && this.win.performance.now) ?
this.win.performance.now.bind(this.win.performance) : Date.now;
/**
* Protected version of emitLifecycleEvent that ensures error does not
* cause promise chain to reject.
* @private {function(string, !Object=)}
*/
this.protectedEmitLifecycleEvent_ = protectFunctionWrapper(
this.emitLifecycleEvent, this,
(err, varArgs) => {
dev().error(TAG, this.element.getAttribute('type'),
'Error on emitLifecycleEvent', err, varArgs) ;
});
/** @const {string} */
this.sentinel = generateSentinel(window);
/**
* Used to indicate whether this slot should be collapsed or not. Marked
* true if the ad response has status 204, is null, or has a null
* arrayBuffer.
* @private {boolean}
*/
this.isCollapsed_ = false;
/**
* Frame in which the creative renders (friendly if validated AMP, xdomain
* otherwise).
* {?HTMLIframeElement}
*/
this.iframe = null;
/**
* TODO(keithwrightbos) - remove once resume behavior is verified.
* {boolean} whether most recent ad request was generated as part
* of resume callback.
*/
this.fromResumeCallback = false;
/** @protected {string} */
this.safeframeVersion = DEFAULT_SAFEFRAME_VERSION;
/**
* @protected {boolean} Indicates whether the ad is currently in the
* process of being refreshed.
*/
this.isRefreshing = false;
/** @protected {boolean} */
this.isRelayoutNeededFlag = false;
/**
* Used as a signal in some of the CSI pings.
* @private @const {string}
*/
this.releaseType_ = getBinaryTypeNumericalCode(getBinaryType(this.win)) ||
'-1';
/**
* Mapping of feature name to value extracted from ad response header
* amp-ff-exps with comma separated pairs of '=' separated key/value.
* @type {!Object<string,string>}
*/
this.postAdResponseExperimentFeatures = {};
/**
* The configuration for amp-analytics. If null, no amp-analytics element
* will be inserted and no analytics events will be fired.
* This will be initialized inside of buildCallback.
* @private {?JsonObject}
*/
this.a4aAnalyticsConfig_ = null;
/**
* The amp-analytics element that for this impl's analytics config. It will
* be null before buildCallback() executes or if the impl does not provide
* an analytice config.
* @private {?Element}
*/
this.a4aAnalyticsElement_ = null;
}
/** @override */
getPriority() {
// Priority used for scheduling preload and layout callback. Because
// AMP creatives will be injected as part of the promise chain created
// within onLayoutMeasure, this is only relevant to non-AMP creatives
// therefore we want this to match the 3p priority.
const isPWA = !this.element.getAmpDoc().isSingleDoc();
// give the ad higher priority if it is inside a PWA
return isPWA ? 1 : 2;
}
/** @override */
isLayoutSupported(layout) {
return isLayoutSizeDefined(layout);
}
/** @override */
isRelayoutNeeded() {
return this.isRelayoutNeededFlag;
}
/** @override */
buildCallback() {
this.creativeSize_ = {
width: this.element.getAttribute('width'),
height: this.element.getAttribute('height'),
};
const upgradeDelayMs = Math.round(this.getResource().getUpgradeDelayMs());
dev().info(TAG,
`upgradeDelay ${this.element.getAttribute('type')}: ${upgradeDelayMs}`);
this.handleLifecycleStage_('upgradeDelay', {
'forced_delta': upgradeDelayMs,
});
this.uiHandler = new AMP.AmpAdUIHandler(this);
const verifier = signatureVerifierFor(this.win);
this.keysetPromise_ =
Services.viewerForDoc(this.getAmpDoc()).whenFirstVisible().then(() => {
this.getSigningServiceNames().forEach(signingServiceName => {
verifier.loadKeyset(signingServiceName);
});
});
this.a4aAnalyticsConfig_ = this.getA4aAnalyticsConfig();
if (this.a4aAnalyticsConfig_) {
// TODO(warrengm): Consider having page-level singletons for networks that
// use the same config for all ads.
this.a4aAnalyticsElement_ = insertAnalyticsElement(
this.element, this.a4aAnalyticsConfig_, true /* loadAnalytics */);
}
}
/** @override */
renderOutsideViewport() {
// Ensure non-verified AMP creatives are throttled.
if (!this.isVerifiedAmpCreative_ && is3pThrottled(this.win)) {
this.handleLifecycleStage_('throttled3p');
return false;
}
// Otherwise the ad is good to go.
const elementCheck = getAmpAdRenderOutsideViewport(this.element);
return elementCheck !== null ?
elementCheck : super.renderOutsideViewport();
}
/**
* To be overridden by network specific implementation indicating if element
* (and environment generally) are valid for sending XHR queries.
* @return {boolean} whether element is valid and ad request should be
* sent. If false, no ad request is sent and slot will be collapsed if
* possible.
*/
isValidElement() {
return true;
}
/**
* @return {boolean} whether ad request should be delayed until
* renderOutsideViewport is met.
*/
delayAdRequestEnabled() {
return false;
}
/**
* Returns preconnect urls for A4A. Ad network should overwrite in their
* Fast Fetch implementation and return an array of urls for the runtime to
* preconnect to.
* @return {!Array<string>}
*/
getPreconnectUrls() {
return [];
}
/**
* Returns prefetch urls for A4A. Ad network should overwrite in their
* Fast Fetch implementation and return an array of urls for the runtime to
* prefetch.
* @return {!Array<string>}
*/
getPrefetchUrls() {
return [];
}
/**
* Returns true if this element was loaded from an amp-ad element. For use by
* network-specific implementations that don't want to allow themselves to be
* embedded directly into a page.
* @return {boolean}
*/
isAmpAdElement() {
return this.element.tagName == 'AMP-AD' ||
this.element.tagName == 'AMP-EMBED';
}
/**
* Prefetches and preconnects URLs related to the ad using adPreconnect
* registration which assumes ad request domain used for 3p is applicable.
* @param {boolean=} unusedOnLayout
* @override
*/
preconnectCallback(unusedOnLayout) {
this.preconnect.preload(this.getSafeframePath_());
this.preconnect.preload(getDefaultBootstrapBaseUrl(this.win, 'nameframe'));
const preconnect = this.getPreconnectUrls();
// NOTE(keithwrightbos): using onLayout to indicate if preconnect should be
// given preferential treatment. Currently this would be false when
// relevant (i.e. want to preconnect on or before onLayoutMeasure) which
// causes preconnect to delay for 1 sec (see custom-element#preconnect)
// therefore hard coding to true.
// NOTE(keithwrightbos): Does not take isValidElement into account so could
// preconnect unnecessarily, however it is assumed that isValidElement
// matches amp-ad loader predicate such that A4A impl does not load.
if (preconnect) {
preconnect.forEach(p => {
this.preconnect.url(p, true);
});
}
}
/** @override */
resumeCallback() {
// FIE that was not destroyed on unlayoutCallback does not require a new
// ad request.
if (this.friendlyIframeEmbed_) {
return;
}
this.handleLifecycleStage_('resumeCallback');
this.fromResumeCallback = true;
// If layout of page has not changed, onLayoutMeasure will not be called
// so do so explicitly.
const resource = this.getResource();
if (resource.hasBeenMeasured() && !resource.isMeasureRequested()) {
this.onLayoutMeasure();
}
}
/**
* @return {!../../../src/service/resource.Resource}
* @visibileForTesting
*/
getResource() {
return this.element.getResources().getResourceForElement(this.element);
}
/**
* @return {boolean} whether adPromise was initialized (indicator of
* element validity).
* @protected
*/
hasAdPromise() {
return !!this.adPromise_;
}
/**
* @return {boolean} whether environment/element should initialize ad request
* promise chain.
* @private
*/
shouldInitializePromiseChain_() {
const slotRect = this.getIntersectionElementLayoutBox();
if (this.getLayout() != Layout.FLUID &&
(slotRect.height == 0 || slotRect.width == 0)) {
dev().fine(
TAG, 'onLayoutMeasure canceled due height/width 0', this.element);
return false;
}
if (!isAdPositionAllowed(this.element, this.win)) {
user().warn(TAG, `<${this.element.tagName}> is not allowed to be ` +
`placed in elements with position:fixed: ${this.element}`);
return false;
}
// OnLayoutMeasure can be called when page is in prerender so delay until
// visible. Assume that it is ok to call isValidElement as it should
// only being looking at window, immutable properties (i.e. location) and
// its element ancestry.
if (!this.isValidElement()) {
// TODO(kjwright): collapse?
user().warn(TAG, this.element.getAttribute('type'),
'Amp ad element ignored as invalid', this.element);
return false;
}
return true;
}
/** @override */
onLayoutMeasure() {
this.initiateAdRequest();
}
/**
* This is the entry point into the ad promise chain.
*
* Calling this function will initiate the following sequence of events: ad
* url construction, ad request issuance, creative verification, and metadata
* parsing.
*
* @protected
*/
initiateAdRequest() {
if (this.xOriginIframeHandler_) {
this.xOriginIframeHandler_.onLayoutMeasure();
}
if (this.adPromise_ || !this.shouldInitializePromiseChain_()) {
return;
}
// If in localDev `type=fake` Ad specifies `force3p`, it will be forced
// to go via 3p.
if (getMode().localDev &&
this.element.getAttribute('type') == 'fake' &&
this.element.getAttribute('force3p') == 'true') {
this.adUrl_ = this.getAdUrl();
this.adPromise_ = Promise.resolve();
return;
}
// Increment unique promise ID so that if its value changes within the
// promise chain due to cancel from unlayout, the promise will be rejected.
++this.promiseId_;
// Shorthand for: reject promise if current promise chain is out of date.
const checkStillCurrent = this.verifyStillCurrent();
// Return value from this chain: True iff rendering was "successful"
// (i.e., shouldn't try to render later via iframe); false iff should
// try to render later in iframe.
// Cases to handle in this chain:
// - Everything ok => Render; return true
// - Empty network response returned => Don't render; return true
// - Can't parse creative out of response => Don't render; return false
// - Can parse, but creative is empty => Don't render; return true
// - Validation fails => return false
// - Rendering fails => return false
// - Chain cancelled => don't return; drop error
// - Uncaught error otherwise => don't return; percolate error up
this.adPromise_ = Services.viewerForDoc(this.getAmpDoc()).whenFirstVisible()
.then(() => {
checkStillCurrent();
// See if experiment that delays request until slot is within
// renderOutsideViewport. Within render outside viewport will not
// resolve if already within viewport thus the check for already
// meeting the definition as opposed to waiting on the promise.
if (this.delayAdRequestEnabled() &&
!this.getResource().renderOutsideViewport()) {
return this.getResource().whenWithinRenderOutsideViewport();
}
})
// This block returns the ad URL, if one is available.
/** @return {!Promise<?string>} */
.then(() => {
checkStillCurrent();
return /** @type {!Promise<?string>} */(
this.getAdUrl(this.tryExecuteRealTimeConfig_()));
})
// This block returns the (possibly empty) response to the XHR request.
/** @return {!Promise<?Response>} */
.then(adUrl => {
checkStillCurrent();
this.adUrl_ = adUrl;
this.handleLifecycleStage_('urlBuilt');
return adUrl && this.sendXhrRequest(adUrl);
})
// The following block returns either the response (as a {bytes, headers}
// object), or null if no response is available / response is empty.
/** @return {?Promise<?{bytes: !ArrayBuffer, headers: !Headers}>} */
.then(fetchResponse => {
checkStillCurrent();
this.handleLifecycleStage_('adRequestEnd');
// If the response is null, we want to return null so that
// unlayoutCallback will attempt to render via x-domain iframe,
// assuming ad url or creative exist.
if (!fetchResponse) {
return null;
}
if (fetchResponse.headers && fetchResponse.headers.has(
EXPERIMENT_FEATURE_HEADER_NAME)) {
this.populatePostAdResponseExperimentFeatures_(
fetchResponse.headers.get(EXPERIMENT_FEATURE_HEADER_NAME));
}
if (getMode().localDev && this.win.location &&
this.win.location.search) {
// Allow for setting experiment features via query param which
// will potentially override values returned in response.
const match = /(?:\?|&)a4a_feat_exp=([^&]+)/.exec(
this.win.location.search);
if (match && match[1]) {
dev().info(TAG, `Using debug exp features: ${match[1]}`);
this.populatePostAdResponseExperimentFeatures_(
tryDecodeUriComponent(match[1]));
}
}
// If the response has response code 204, or arrayBuffer is null,
// collapse it.
if (!fetchResponse.arrayBuffer || fetchResponse.status == 204) {
this.forceCollapse();
return Promise.reject(NO_CONTENT_RESPONSE);
}
// TODO(tdrl): Temporary, while we're verifying whether SafeFrame is
// an acceptable solution to the 'Safari on iOS doesn't fetch
// iframe src from cache' issue. See
// https://github.com/ampproject/amphtml/issues/5614
const method = this.getNonAmpCreativeRenderingMethod(
fetchResponse.headers.get(RENDERING_TYPE_HEADER));
this.experimentalNonAmpCreativeRenderMethod_ = method;
const safeframeVersionHeader =
fetchResponse.headers.get(SAFEFRAME_VERSION_HEADER);
if (/^[0-9-]+$/.test(safeframeVersionHeader) &&
safeframeVersionHeader != DEFAULT_SAFEFRAME_VERSION) {
this.safeframeVersion = safeframeVersionHeader;
this.preconnect.preload(this.getSafeframePath_());
}
// Note: Resolving a .then inside a .then because we need to capture
// two fields of fetchResponse, one of which is, itself, a promise,
// and one of which isn't. If we just return
// fetchResponse.arrayBuffer(), the next step in the chain will
// resolve it to a concrete value, but we'll lose track of
// fetchResponse.headers.
return fetchResponse.arrayBuffer().then(bytes => {
if (bytes.byteLength == 0) {
// The server returned no content. Instead of displaying a blank
// rectangle, we collapse the slot instead.
this.forceCollapse();
return Promise.reject(NO_CONTENT_RESPONSE);
}
return {
bytes,
headers: fetchResponse.headers,
};
});
})
/** @return {!Promise<?ArrayBuffer>} */
.then(responseParts => {
checkStillCurrent();
// Keep a handle to the creative body so that we can render into
// SafeFrame or NameFrame later, if necessary. TODO(tdrl): Temporary,
// while we
// assess whether this is the right solution to the Safari+iOS iframe
// src cache issue. If we decide to keep a SafeFrame-like solution,
// we should restructure the promise chain to pass this info along
// more cleanly, without use of an object variable outside the chain.
if (!responseParts) {
return Promise.resolve();
}
const {bytes, headers} = responseParts;
const size = this.extractSize(responseParts.headers);
this.creativeSize_ = size || this.creativeSize_;
if (this.experimentalNonAmpCreativeRenderMethod_ !=
XORIGIN_MODE.CLIENT_CACHE &&
bytes) {
this.creativeBody_ = bytes;
}
return this.maybeValidateAmpCreative(bytes, headers);
})
.then(creative => {
checkStillCurrent();
// Need to know if creative was verified as part of render outside
// viewport but cannot wait on promise. Sadly, need a state a
// variable.
this.isVerifiedAmpCreative_ = !!creative;
return creative && utf8Decode(creative);
})
// This block returns CreativeMetaDataDef iff the creative was verified
// as AMP and could be properly parsed for friendly iframe render.
/** @return {?CreativeMetaDataDef} */
.then(creativeDecoded => {
checkStillCurrent();
// Note: It's critical that #getAmpAdMetadata be called
// on precisely the same creative that was validated
// via #validateAdResponse_. See GitHub issue
// https://github.com/ampproject/amphtml/issues/4187
let creativeMetaDataDef;
if (!creativeDecoded ||
!(creativeMetaDataDef = this.getAmpAdMetadata(creativeDecoded))) {
return null;
}
// Update priority.
this.updatePriority(0);
// Load any extensions; do not wait on their promises as this
// is just to prefetch.
const extensions = Services.extensionsFor(this.win);
creativeMetaDataDef.customElementExtensions.forEach(
extensionId => extensions.preloadExtension(extensionId));
// Preload any fonts.
(creativeMetaDataDef.customStylesheets || []).forEach(font =>
this.preconnect.preload(font.href));
// Preload any AMP images.
(creativeMetaDataDef.images || []).forEach(image =>
isSecureUrl(image) && this.preconnect.preload(image));
return creativeMetaDataDef;
})
.catch(error => {
if (error == NO_CONTENT_RESPONSE) {
return {
minifiedCreative: '',
customElementExtensions: [],
customStylesheets: [],
};
}
// If error in chain occurs, report it and return null so that
// layoutCallback can render via cross domain iframe assuming ad
// url or creative exist.
this.promiseErrorHandler_(error);
return null;
});
}
/**
* This block returns the ad creative if it exists and validates as AMP;
* null otherwise.
* @param {!ArrayBuffer} bytes
* @param {!Headers} headers
* @return {!Promise<?ArrayBuffer>}
*/
maybeValidateAmpCreative(bytes, headers) {
this.handleLifecycleStage_('adResponseValidateStart');
const checkStillCurrent = this.verifyStillCurrent();
return this.keysetPromise_
.then(() => signatureVerifierFor(this.win)
.verify(bytes, headers, (eventName, extraVariables) => {
this.handleLifecycleStage_(
eventName, extraVariables);
}))
.then(status => {
checkStillCurrent();
if (getMode().localDev &&
this.element.getAttribute('type') == 'fake') {
// do not verify signature for fake type ad
status = VerificationStatus.OK;
}
this.handleLifecycleStage_('adResponseValidateEnd', {
'signatureValidationResult': status,
'releaseType': this.releaseType_,
});
switch (status) {
case VerificationStatus.OK:
return bytes;
case VerificationStatus.UNVERIFIED:
return null;
case VerificationStatus.CRYPTO_UNAVAILABLE:
return this.shouldPreferentialRenderWithoutCrypto() ?
bytes : null;
// TODO(@taymonbeal, #9274): differentiate between these
case VerificationStatus.ERROR_KEY_NOT_FOUND:
case VerificationStatus.ERROR_SIGNATURE_MISMATCH:
user().error(
TAG, this.element.getAttribute('type'),
'Signature verification failed');
return null;
}
});
}
/**
* Populates object mapping of feature to value used for post ad response
* behavior experimentation. Assumes comma separated, = delimited key/value
* pairs. If key appears more than once, last value wins.
* @param {string} input
* @private
*/
populatePostAdResponseExperimentFeatures_(input) {
input.split(',').forEach(line => {
if (!line) {
return;
}
const parts = line.split('=');
if (parts.length != 2 || !parts[0]) {
dev().warn(TAG, `invalid experiment feature ${line}`);
return;
}
this.postAdResponseExperimentFeatures[parts[0]] = parts[1];
});
}
/**
* Refreshes ad slot by fetching a new creative and rendering it. This leaves
* the current creative displayed until the next one is ready.
*
* @param {function()} refreshEndCallback When called, this function will
* restart the refresh cycle.
* @return {Promise} A promise that resolves when all asynchronous portions of
* the refresh function complete. This is particularly handy for testing.
*/
refresh(refreshEndCallback) {
dev().assert(!this.isRefreshing);
this.isRefreshing = true;
this.tearDownSlot();
this.initiateAdRequest();
dev().assert(this.adPromise_);
const promiseId = this.promiseId_;
return this.adPromise_.then(() => {
if (!this.isRefreshing || promiseId != this.promiseId_) {
// If this refresh cycle was canceled, such as in a no-content
// response case, keep showing the old creative.
refreshEndCallback();
return;
}
return this.mutateElement(() => {
this.togglePlaceholder(true);
// This delay provides a 1 second buffer where the ad loader is
// displayed in between the creatives.
return Services.timerFor(this.win).promise(1000).then(() => {
this.isRelayoutNeededFlag = true;
this.getResource().layoutCanceled();
Services.resourcesForDoc(this.getAmpDoc())
./*OK*/requireLayout(this.element);
});
});
});
}
/**
* Handles uncaught errors within promise flow.
* @param {*} error
* @param {boolean=} opt_ignoreStack
* @private
*/
promiseErrorHandler_(error, opt_ignoreStack) {
if (isCancellation(error)) {
// Rethrow if cancellation.
throw error;
}
if (error && error.message) {
error = duplicateErrorIfNecessary(/** @type {!Error} */(error));
} else {
error = new Error('unknown error ' + error);
}
if (opt_ignoreStack) {
error.ignoreStack = opt_ignoreStack;
}
// Add `type` to the message. Ensure to preserve the original stack.
const type = this.element.getAttribute('type') || 'notype';
if (error.message.indexOf(`${TAG}: ${type}:`) != 0) {
error.message = `${TAG}: ${type}: ${error.message}`;
}
// Additional arguments.
assignAdUrlToError(/** @type {!Error} */(error), this.adUrl_);
if (getMode().development || getMode().localDev || getMode().log) {
user().error(TAG, error);
} else {
user().warn(TAG, error);
// Report with 1% sampling as an expected dev error.
if (Math.random() < 0.01) {
dev().expectedError(TAG, error);
}
}
}
/** @override */
layoutCallback() {
if (this.isRefreshing) {
this.destroyFrame(true);
}
return this.attemptToRenderCreative();
}
/**
* Attemps to render the returned creative following the resolution of the
* adPromise.
*
* @return {!Promise<boolean>|!Promise<undefined>} A promise that resolves
* when the rendering attempt has finished.
* @protected
*/
attemptToRenderCreative() {
// Promise may be null if element was determined to be invalid for A4A.
if (!this.adPromise_) {
if (this.shouldInitializePromiseChain_()) {
dev().error(TAG, 'Null promise in layoutCallback');
}
return Promise.resolve();
}
// There's no real throttling with A4A, but this is the signal that is
// most comparable with the layout callback for 3p ads.
this.handleLifecycleStage_('preAdThrottle');
const layoutCallbackStart = this.getNow_();
const checkStillCurrent = this.verifyStillCurrent();
// Promise chain will have determined if creative is valid AMP.
return this.adPromise_.then(creativeMetaData => {
checkStillCurrent();
const delta = this.getNow_() - layoutCallbackStart;
this.handleLifecycleStage_('layoutAdPromiseDelay', {
layoutAdPromiseDelay: Math.round(delta),
isAmpCreative: !!creativeMetaData,
});
if (this.isCollapsed_) {
return Promise.resolve();
}
// If this.iframe already exists, and we're not currently in the middle
// of refreshing, bail out here. This should only happen in
// testing context, not in production.
if (this.iframe && !this.isRefreshing) {
this.handleLifecycleStage_('iframeAlreadyExists');
return Promise.resolve();
}
if (!creativeMetaData) {
// Non-AMP creative case, will verify ad url existence.
return this.renderNonAmpCreative();