wpcom-proxy-request: Return Promise if no callback specified (Take Tw…

…o) (#39722)

The promise wrapper introduced et al. in #38823 is generic enough for it to make sense to have it in `wpcom-proxy-request`. This commit moves it there. This follows [precedent](https://github.com/Automattic/wp-calypso/blob/bf345c5b040e75808fb2f92c9b9e34e6f126a235/packages/wpcom.js/src/lib/util/send-request.js#L78-L93) set by `wpcom.js`.

Note that this is a technically a breaking change, as noted in the package's `History.md`:

Co-authored-by: Jon Surrell <jon.surrell@automattic.com>

This reverts commit 7f5092a.

.dockerignore

@@ -21,4 +21,3 @@ Dockerfile
 /apps/*/dist/
 /apps/*/types/
 /packages/*/dist/
-/packages/*/types/

.gitignore

@@ -64,6 +64,3 @@ cached-requests.json
 /apps/*/dist/
 /apps/*/types/
 /packages/*/dist/
-# Redundant after https://github.com/Automattic/wp-calypso/pull/39173
-# Safe to remove after some time has passed
-/packages/*/types/

packages/data-stores/src/shared-types.ts

@@ -0,0 +1,4 @@
+export interface WpcomClientCredentials {
+	client_id: string;
+	client_secret: string;
+}

packages/data-stores/src/site/controls.ts

@@ -1,10 +1,18 @@
+/**
+ * External dependencies
+ */
+import wpcomRequest, { requestAllBlogsAccess } from 'wpcom-proxy-request';
+
 /**
  * Internal dependencies
  */
-import { wpcomRequest, WpcomClientCredentials } from '../utils';
 import { CreateSiteAction } from './types';
+import { WpcomClientCredentials } from '../shared-types';
 
 export default function createControls( clientCreds: WpcomClientCredentials ) {
+	requestAllBlogsAccess().catch( () => {
+		throw new Error( 'Could not get all blog access.' );
+	} );
 	return {
 		CREATE_SITE: async ( action: CreateSiteAction ) => {
 			const { authToken, ...providedParams } = action.params;

packages/data-stores/src/site/index.ts

@@ -12,7 +12,7 @@ import * as actions from './actions';
 import * as selectors from './selectors';
 import createControls from './controls';
 import { DispatchFromMap, SelectFromMap } from '../mapped-types';
-import { WpcomClientCredentials } from '../utils';
+import { WpcomClientCredentials } from '../shared-types';
 
 export * from './types';
 export { State };

packages/data-stores/src/user/controls.ts

@@ -1,10 +1,18 @@
+/**
+ * External dependencies
+ */
+import wpcomRequest, { requestAllBlogsAccess } from 'wpcom-proxy-request';
+
 /**
  * Internal dependencies
  */
-import { wpcomRequest, WpcomClientCredentials } from '../utils';
 import { CreateAccountAction } from './types';
+import { WpcomClientCredentials } from '../shared-types';
 
 export default function createControls( clientCreds: WpcomClientCredentials ) {
+	requestAllBlogsAccess().catch( () => {
+		throw new Error( 'Could not get all blog access.' );
+	} );
 	return {
 		CREATE_ACCOUNT: async ( action: CreateAccountAction ) => {
 			const defaultParams = {

packages/data-stores/src/user/index.ts

@@ -13,7 +13,7 @@ import * as resolvers from './resolvers';
 import * as selectors from './selectors';
 import createControls from './controls';
 import { DispatchFromMap, SelectFromMap } from '../mapped-types';
-import { WpcomClientCredentials } from '../utils';
+import { WpcomClientCredentials } from '../shared-types';
 
 export * from './types';
 export { State };

packages/data-stores/tsconfig.json

@@ -29,6 +29,6 @@
 		"incremental": true,
 		"tsBuildInfoFile": "../../.tsc-cache/data-stores"
 	},
-	"files": [ "./src/index.ts", "./global.d.ts" ],
+	"files": [ "./src/index.ts" ],
 	"exclude": [ "**/docs/*", "**/test/*" ]
 }

packages/wpcom-proxy-request/History.md

@@ -1,5 +1,9 @@
 # 6.0.0 / TBD
 
+- Breaking: Return Promise (rather than `XMLHttpRequest` instance) if no callback argument is provided.
+  - In practice, most people have probably been using the callback rather than the returned `XMLHttpRequest` instance, so this shouldn't be a breaking change for most.
+- Add `requestAllBlogsAccess()`.
+- Add a few type definitions.
 - Move the published `build/` folder to `dist/` to align with other Calypso packages
 - Upgrade dependency 'debug' to 4.1.1
 - Remove `component-event` dependency, use `addEventListener`/`removeEventListener` directly

packages/wpcom-proxy-request/package.json

@@ -30,9 +30,11 @@
 	},
 	"files": [
 		"dist",
+		"types",
 		"History.md",
 		"README.md"
 	],
+	"types": "types",
 	"scripts": {
 		"clean": "npx rimraf dist",
 		"prepublish": "npm run clean",

packages/wpcom-proxy-request/src/index.js

@@ -101,7 +101,7 @@ debug( 'using "origin": %o', origin );
  * @param {Function} [fn] - callback response
  * @returns {window.XMLHttpRequest} XMLHttpRequest instance
  */
-const request = ( originalParams, fn ) => {
+const makeRequest = ( originalParams, fn ) => {
 	const params = Object.assign( {}, originalParams );
 
 	debug( 'request(%o)', params );
@@ -170,6 +170,40 @@ const request = ( originalParams, fn ) => {
 	return xhr;
 };
 
+/**
+ * Performs a "proxied REST API request". This happens by calling
+ * `iframe.postMessage()` on the proxy iframe instance, which from there
+ * takes care of WordPress.com user authentication (via the currently
+ * logged-in user's cookies).
+ *
+ * If no function is specified as second parameter, a promise is returned.
+ *
+ * @param {object} originalParams - request parameters
+ * @param {Function} [fn] - callback response
+ * @returns {window.XMLHttpRequest|Promise} XMLHttpRequest instance or Promise
+ */
+const request = ( originalParams, fn ) => {
+	// if callback is provided, behave traditionally
+	if ( 'function' === typeof fn ) {
+		// request method
+		return makeRequest( originalParams, fn );
+	}
+
+	// but if not, return a Promise
+	return new Promise( ( res, rej ) => {
+		makeRequest( originalParams, ( err, response ) => {
+			err ? rej( err ) : res( response );
+		} );
+	} );
+};
+
+/**
+ * Set proxy to "access all users' blogs" mode.
+ */
+export function requestAllBlogsAccess() {
+	return request( { metaAPI: { accessAllUsersBlogs: true } } );
+}
+
 /**
  * Calls the `postMessage()` function on the <iframe>.
  *

packages/wpcom-proxy-request/types/index.d.ts

@@ -0,0 +1,25 @@
+/**
+ * TypeScript type definitions for wpcom-proxy-request
+ *
+ * @todo Migrate `src/index.js` to TypeScript, incorporate these type definitions.
+ * (Needs changes to the build chain, see other packages in the monorepo
+ * for inspiration, e.g. `@automattic/data-stores`.)
+ */
+
+export interface WpcomRequestParams {
+	path?: string;
+	method?: string;
+	apiVersion?: string;
+	body?: object;
+	token?: string;
+	metaAPI?: {
+		accessAllUsersBlogs?: boolean;
+	};
+}
+
+export function reloadProxy(): void;
+
+export function requestAllBlogsAccess(): ReturnType< typeof request >;
+
+export default function request( params: WpcomRequestParams, callback: Function ): XMLHttpRequest;
+export default function request< T >( params: WpcomRequestParams ): Promise< T >;