Update consent string maximum size to 200 bytes (#26741)

* update maximum byte to 200

* nit

extensions/amp-consent/0.1/consent-state-manager.js

@@ -34,6 +34,9 @@ import {dev, devAssert, user} from '../../../src/log';
 const TAG = 'CONSENT-STATE-MANAGER';
 const CID_SCOPE = 'AMP-CONSENT';
 
+/** @visibleForTesting */
+export const CONSENT_STRING_MAX_LENGTH = 200;
+
 export class ConsentStateManager {
   /**
    * Creates an instance of ConsentStateManager.
@@ -346,14 +349,15 @@ export class ConsentInstance {
       }
 
       const consentStr = consentInfo['consentString'];
-      if (consentStr && consentStr.length > 150) {
+      if (consentStr && consentStr.length > CONSENT_STRING_MAX_LENGTH) {
         // Verify the length of consentString.
-        // 150 * 2 (utf8Encode) * 4/3 (base64) = 400 bytes.
+        // 200 * 2 (utf8Encode) * 4/3 (base64) = 533 bytes.
         // TODO: Need utf8Encode if necessary.
         user().error(
           TAG,
-          'Cannot store consentString which length exceeds 150 ' +
-            'Previous stored consentInfo will be cleared'
+          'Cannot store consentString which length exceeds %s. ' +
+            'Previous stored consentInfo will be cleared',
+          CONSENT_STRING_MAX_LENGTH
         );
         // If new consentInfo value cannot be stored, need to remove previous
         // value

extensions/amp-consent/0.1/test/test-consent-state-manager.js

@@ -18,7 +18,11 @@ import {
   composeStoreValue,
   constructConsentInfo,
 } from '../consent-info';
-import {ConsentInstance, ConsentStateManager} from '../consent-state-manager';
+import {
+  CONSENT_STRING_MAX_LENGTH,
+  ConsentInstance,
+  ConsentStateManager,
+} from '../consent-state-manager';
 import {dev} from '../../../../src/log';
 import {macroTask} from '../../../../testing/yield';
 import {
@@ -146,9 +150,8 @@ describes.realWin('ConsentStateManager', {amp: 1}, env => {
       it('update consent string that exceeds max size', function*() {
         expectAsyncConsoleError(/Cannot store consentString/);
         manager.registerConsentInstance('test', {});
-        const MAX_LENGTH = 150;
         let testStr = 'a';
-        for (let i = 0; i < MAX_LENGTH; i++) {
+        for (let i = 0; i < CONSENT_STRING_MAX_LENGTH; i++) {
           testStr += 'a';
         }
         manager.updateConsentInstanceState(
@@ -302,9 +305,8 @@ describes.realWin('ConsentStateManager', {amp: 1}, env => {
 
         it('remove consentInfo when consentStr length exceeds', function*() {
           expectAsyncConsoleError(/Cannot store consentString/);
-          const MAX_LENGTH = 150;
           let testStr = 'a';
-          for (let i = 0; i < MAX_LENGTH; i++) {
+          for (let i = 0; i < CONSENT_STRING_MAX_LENGTH; i++) {
             testStr += 'a';
           }
           instance.update(CONSENT_ITEM_STATE.ACCEPTED, testStr);

extensions/amp-consent/integrating-consent.md

@@ -14,7 +14,7 @@ To add your consent management service to AMP runtime, it is expected that you:
 - Meet the restrictions that the AMP runtime applies to ensure a good user experience. These includes
   - Enforce the size of the consent prompt. The only two allowed sizes are the initial size (`width: 100vw`, `height: 30vh`), and the full screen size (`width: 100vw`, `height: 100%`) after user interactions.
   - A default placeholder will be displayed before the consent prompt iframe is ready.
-  - Enforce the size of the stored consent information. 150 character length is the current limit. Please [file an issue](https://github.com/ampproject/amphtml/issues/new) if you find that not sufficient.
+  - Enforce the size of the stored consent information. 200 character length is the current limit. Please [file an issue](https://github.com/ampproject/amphtml/issues/new) if you find that not sufficient.
 - Understand that including `<amp-consent type='yourName'></amp-consent>` on the page won't block any components by default. **Please make sure to inform your service users to block AMP components either by the `<meta name="amp-consent-blocking">` metaTag, or the `data-block-on-consent` attribute.**
 - Understand that AMP Consent doesn't attempt to interpret the consent info string from the CMP. Vendors can access the consent info string from CMPs via [provided APIs](https://github.com/ampproject/amphtml/blob/master/ads/README.md#amp-consent-integration). It's up to the CMP and service provider vendors to agree on the format of the consent info string.
 - Create an [Intent-To-Implement issue](../../CONTRIBUTING.md#contributing-features) stating that you'll be adding support to your CMP service to AMP. A great start point is to follow the `_ping_` CMP service implementation that the AMP team creates for testing purpose.