Add typings for WebChannel (#2385)

Author: schmidt-sebastian

packages/firestore/src/platform_browser/webchannel_connection.ts

@@ -20,6 +20,7 @@ import {
   ErrorCode,
   EventType,
   WebChannel,
+  WebChannelError,
   WebChannelOptions,
   XhrIo
 } from '@firebase/webchannel-wrapper';
@@ -98,9 +99,7 @@ export class WebChannelConnection implements Connection {
     const url = this.makeUrl(rpcName);
 
     return new Promise((resolve: Resolver<Resp>, reject: Rejecter) => {
-      // XhrIo doesn't have TS typings.
-      // eslint-disable-next-line @typescript-eslint/no-explicit-any
-      const xhr: any = new XhrIo();
+      const xhr = new XhrIo();
       xhr.listenOnce(EventType.COMPLETE, () => {
         try {
           switch (xhr.getLastErrorCode()) {
@@ -125,7 +124,8 @@ export class WebChannelConnection implements Connection {
                 xhr.getResponseText()
               );
               if (status > 0) {
-                const responseError = xhr.getResponseJson().error;
+                const responseError = (xhr.getResponseJson() as WebChannelError)
+                  .error;
                 if (
                   !!responseError &&
                   !!responseError.status &&
@@ -272,9 +272,7 @@ export class WebChannelConnection implements Connection {
 
     const url = urlParts.join('');
     log.debug(LOG_TAG, 'Creating WebChannel: ' + url + ' ' + request);
-    // Use any because listen isn't defined on it.
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    const channel = webchannelTransport.createWebChannel(url, request) as any;
+    const channel = webchannelTransport.createWebChannel(url, request);
 
     // WebChannel supports sending the first message with the handshake - saving
     // a network round trip. However, it will have to call send in the same
@@ -310,14 +308,14 @@ export class WebChannelConnection implements Connection {
     // Note that eventually this function could go away if we are confident
     // enough the code is exception free.
     const unguardedEventListen = <T>(
-      type: WebChannel.EventType,
+      type: string,
       fn: (param?: T) => void
     ): void => {
       // TODO(dimond): closure typing seems broken because WebChannel does
       // not implement goog.events.Listenable
-      channel.listen(type, (param?: T) => {
+      channel.listen(type, (param: unknown) => {
         try {
-          fn(param);
+          fn(param as T);
         } catch (e) {
           setTimeout(() => {
             throw e;
@@ -371,10 +369,10 @@ export class WebChannelConnection implements Connection {
           // compatible with the bug we need to check either condition. The latter
           // can be removed once the fix has been rolled out.
           // Use any because msgData.error is not typed.
-          // eslint-disable-next-line @typescript-eslint/no-explicit-any
-          const msgDataAsAny: any = msgData;
+          const msgDataOrError: WebChannelError | object = msgData;
           const error =
-            msgDataAsAny.error || (msgDataAsAny[0] && msgDataAsAny[0].error);
+            msgDataOrError.error ||
+            (msgDataOrError as WebChannelError[])[0]?.error;
           if (error) {
             log.debug(LOG_TAG, 'WebChannel received error:', error);
             // error.status will be a string like 'OK' or 'NOT_FOUND'.

packages/webchannel-wrapper/src/index.d.ts

@@ -15,23 +15,73 @@
  * limitations under the License.
  */
 
-// TODO(mikelehen): Flesh out proper types (or figure out how to generate via
-// clutz or something).
-export class XhrIo {}
-export const ErrorCode: any;
-export const EventType: any;
+// WARNING: This is not a complete set of types exported by WebChannelWrapper.
+// It is merely meant to support the usage patterns of the Firestore SDK.
+
+export var EventType: {
+  COMPLETE: string;
+};
+
 export namespace WebChannel {
-  export type EventType = any;
-  export const EventType: any;
+  export var EventType: {
+    OPEN: string;
+    CLOSE: string;
+    ERROR: string;
+    MESSAGE: string;
+  };
+}
+
+export var ErrorCode: {
+  NO_ERROR: number;
+  HTTP_ERROR: number;
+  TIMEOUT: number;
+};
+
+export interface Headers {
+  [name: string]: string | number;
+}
+
+export interface WebChannelError {
+  error?: { status: string; message: string };
 }
 
-type StringMap = { [key: string]: string };
+export class XhrIo {
+  send(
+    url: string,
+    method?: string,
+    body?: string,
+    headers?: Headers,
+    timeoutInterval?: number
+  ): void;
+
+  getLastErrorCode(): number;
+
+  getLastError(): string;
+
+  getStatus(): number;
+
+  getResponseText(): string;
+
+  getResponseJson(): WebChannelError | object;
+
+  listenOnce(type: string, cb: (param: unknown) => void): void;
+}
 
 export interface WebChannelOptions {
-  messageHeaders?: StringMap;
-  initMessageHeaders?: StringMap;
+  messageHeaders?: {
+    // To ensure compatibility with property minifcation tools, keys need to
+    // be listed explicity.
+    [k: string]: never;
+  };
+  initMessageHeaders?: {
+    // To ensure compatibility with property minifcation tools, keys need to
+    // be listed explicity.
+    [k: string]: never;
+  };
   messageContentType?: string;
-  messageUrlParams?: StringMap;
+  messageUrlParams?: {
+    database?: string;
+  };
   clientProtocolHeaderRequired?: boolean;
   concurrentRequestLimit?: number;
   supportsCrossDomainXhr?: boolean;
@@ -44,13 +94,22 @@ export interface WebChannelOptions {
   fastHandshake?: boolean;
   disableRedac?: boolean;
   clientProfile?: string;
-  internalChannelParams?: { [key: string]: boolean | number };
+  internalChannelParams?: {
+    forwardChannelRequestTimeoutMs?: number;
+  };
   xmlHttpFactory?: unknown;
   requestRefreshThresholds?: { [key: string]: number };
 }
 
+export interface WebChannel {
+  open(): void;
+  close(): void;
+  listen(type: string, cb: (param: unknown) => void): void;
+  send(msg: unknown): void;
+}
+
 export interface WebChannelTransport {
-  createWebChannel(url: string, options: WebChannelOptions): any;
+  createWebChannel(url: string, options: WebChannelOptions): WebChannel;
 }
 
 export function createWebChannelTransport(): WebChannelTransport;

packages/webchannel-wrapper/src/index.js

@@ -68,8 +68,6 @@ goog.net.XhrIo.prototype['getLastError'] =
 goog.net.XhrIo.prototype['getLastErrorCode'] =
   goog.net.XhrIo.prototype.getLastErrorCode;
 goog.net.XhrIo.prototype['getStatus'] = goog.net.XhrIo.prototype.getStatus;
-goog.net.XhrIo.prototype['getStatusText'] =
-  goog.net.XhrIo.prototype.getStatusText;
 goog.net.XhrIo.prototype['getResponseJson'] =
   goog.net.XhrIo.prototype.getResponseJson;
 goog.net.XhrIo.prototype['getResponseText'] =