From 86f0caae389c3264b81dee4ea699b4c56853f883 Mon Sep 17 00:00:00 2001
From: Sebastian Halder <sebastian.halder@gmx.de>
Date: Fri, 13 Oct 2023 05:29:19 +0000
Subject: [PATCH] Support less prominent streaming methods: client-streaming
 and bidirectional streaming

---
 .../src/index.ts                              | 135 ++++++++++++------
 1 file changed, 89 insertions(+), 46 deletions(-)

diff --git a/packages/nice-grpc-client-middleware-devtools/src/index.ts b/packages/nice-grpc-client-middleware-devtools/src/index.ts
index 1814a8af..82f9bbff 100644
--- a/packages/nice-grpc-client-middleware-devtools/src/index.ts
+++ b/packages/nice-grpc-client-middleware-devtools/src/index.ts
@@ -1,4 +1,4 @@
-import { isAbortError } from 'abort-controller-x';
+import {isAbortError} from 'abort-controller-x';
 import {
   CallOptions,
   ClientError,
@@ -10,7 +10,7 @@ import {
 export type DevtoolsLoggingOptions = {
   /**
    * Skip logging abort errors.
-   * 
+   *
    * By default, abort errors are logged.
    */
   skipAbortErrorLogging?: boolean;
@@ -19,7 +19,7 @@ export type DevtoolsLoggingOptions = {
 export const devtoolsUnaryLoggingMiddleware: ClientMiddleware<DevtoolsLoggingOptions> =
   async function* devtoolsLoggingMiddleware<Request, Response>(
     call: ClientMiddlewareCall<Request, Response>,
-    options: CallOptions & Partial<DevtoolsLoggingOptions>
+    options: CallOptions & Partial<DevtoolsLoggingOptions>,
   ): AsyncGenerator<Response, Response | void, undefined> {
     // skip streaming calls
     if (call.requestStream || call.responseStream) {
@@ -27,7 +27,7 @@ export const devtoolsUnaryLoggingMiddleware: ClientMiddleware<DevtoolsLoggingOpt
     }
 
     // log unary calls
-    const { path } = call.method;
+    const {path} = call.method;
     const reqObj = getAsObject(call.request);
 
     try {
@@ -41,7 +41,7 @@ export const devtoolsUnaryLoggingMiddleware: ClientMiddleware<DevtoolsLoggingOpt
           response: resObj,
           type: '__GRPCWEB_DEVTOOLS__',
         },
-        '*'
+        '*',
       );
       return result;
     } catch (error) {
@@ -59,7 +59,7 @@ export const devtoolsUnaryLoggingMiddleware: ClientMiddleware<DevtoolsLoggingOpt
             request: reqObj,
             type: '__GRPCWEB_DEVTOOLS__',
           },
-          '*'
+          '*',
         );
       } else if (isAbortError(error) && error instanceof Error) {
         if (!options.skipAbortErrorLogging) {
@@ -76,7 +76,7 @@ export const devtoolsUnaryLoggingMiddleware: ClientMiddleware<DevtoolsLoggingOpt
               request: reqObj,
               type: '__GRPCWEB_DEVTOOLS__',
             },
-            '*'
+            '*',
           );
         }
       } else if (error instanceof Error) {
@@ -93,7 +93,7 @@ export const devtoolsUnaryLoggingMiddleware: ClientMiddleware<DevtoolsLoggingOpt
             request: reqObj,
             type: '__GRPCWEB_DEVTOOLS__',
           },
-          '*'
+          '*',
         );
       }
 
@@ -104,7 +104,7 @@ export const devtoolsUnaryLoggingMiddleware: ClientMiddleware<DevtoolsLoggingOpt
 export const devtoolsStreamLoggingMiddleware: ClientMiddleware<DevtoolsLoggingOptions> =
   async function* devtoolsLoggingMiddleware<Request, Response>(
     call: ClientMiddlewareCall<Request, Response>,
-    options: CallOptions & Partial<DevtoolsLoggingOptions>
+    options: CallOptions & Partial<DevtoolsLoggingOptions>,
   ): AsyncGenerator<Response, Response | void, undefined> {
     // skip unary calls
     if (!call.responseStream && !call.requestStream) {
@@ -112,38 +112,34 @@ export const devtoolsStreamLoggingMiddleware: ClientMiddleware<DevtoolsLoggingOp
     }
 
     // log streaming calls
-    const { path } = call.method;
-    const reqObj = getAsObject(call.request);
+    const {path} = call.method;
 
-    let first = true;
     try {
-      for await (const response of call.next(call.request, options)) {
-        const resObj = getAsObject(response);
-        if (first) {
-          // log the request object only once
-          window.postMessage(
-            {
-              method: path,
-              methodType: 'server_streaming',
-              request: reqObj,
-              type: '__GRPCWEB_DEVTOOLS__',
-            },
-            '*'
-          );
-          first = false;
+      if (!call.requestStream) {
+        // server streaming, the most prominent streaming option in grpc-web
+        let first = true;
+        for await (const response of call.next(call.request, options)) {
+          if (first) {
+            // log the request object only once and after the first response to not have duplicate logs in case of an error
+            logStreamingRequestMessage(call.request, path);
+            first = false;
+          }
+          logStreamingResponseMessage(response, path);
+          yield response;
+        }
+        return;
+      } else {
+        const request = emitRequestMessages(call.request, path);
+        if (!call.responseStream) {
+          // client streaming
+          const response = yield* call.next(request, options);
+          logStreamingResponseMessage(response, path);
+          return response;
+        } else {
+          // bidirectional streaming
+          yield* emitResponseMessages(call.next(request, options), path);
+          return;
         }
-        // log the response
-        window.postMessage(
-          {
-            method: path,
-            methodType: 'server_streaming',
-            response: resObj,
-            type: '__GRPCWEB_DEVTOOLS__',
-          },
-          '*'
-        );
-
-        yield response;
       }
     } catch (error) {
       if (error instanceof ClientError) {
@@ -159,7 +155,7 @@ export const devtoolsStreamLoggingMiddleware: ClientMiddleware<DevtoolsLoggingOp
             methodType: 'server_streaming',
             type: '__GRPCWEB_DEVTOOLS__',
           },
-          '*'
+          '*',
         );
       } else if (isAbortError(error) && error instanceof Error) {
         if (!options.skipAbortErrorLogging) {
@@ -175,7 +171,7 @@ export const devtoolsStreamLoggingMiddleware: ClientMiddleware<DevtoolsLoggingOp
               methodType: 'server_streaming',
               type: '__GRPCWEB_DEVTOOLS__',
             },
-            '*'
+            '*',
           );
         }
       } else if (error instanceof Error) {
@@ -191,7 +187,7 @@ export const devtoolsStreamLoggingMiddleware: ClientMiddleware<DevtoolsLoggingOp
             methodType: 'server_streaming',
             type: '__GRPCWEB_DEVTOOLS__',
           },
-          '*'
+          '*',
         );
       }
 
@@ -199,10 +195,11 @@ export const devtoolsStreamLoggingMiddleware: ClientMiddleware<DevtoolsLoggingOp
     }
   };
 
-export const devtoolsLoggingMiddleware: ClientMiddleware<DevtoolsLoggingOptions> = composeClientMiddleware(
-  devtoolsUnaryLoggingMiddleware,
-  devtoolsStreamLoggingMiddleware
-);
+export const devtoolsLoggingMiddleware: ClientMiddleware<DevtoolsLoggingOptions> =
+  composeClientMiddleware(
+    devtoolsUnaryLoggingMiddleware,
+    devtoolsStreamLoggingMiddleware,
+  );
 
 // check whether the given object has toObject() method and return the object
 // otherwise return the object itself
@@ -213,4 +210,50 @@ function getAsObject(obj: any) {
   }
   // ts-proto
   return obj;
-}
\ No newline at end of file
+}
+
+async function* emitRequestMessages<T>(
+  iterable: AsyncIterable<T>,
+  path: string,
+): AsyncIterable<T> {
+  for await (const request of iterable) {
+    logStreamingRequestMessage(request, path);
+    yield request;
+  }
+}
+
+async function* emitResponseMessages<T>(
+  iterable: AsyncIterable<T>,
+  path: string,
+): AsyncIterable<T> {
+  for await (const reponse of iterable) {
+    logStreamingResponseMessage(reponse, path);
+    yield reponse;
+  }
+}
+
+function logStreamingResponseMessage<T>(response: T, path: string) {
+  const resObj = getAsObject(response);
+  window.postMessage(
+    {
+      method: path,
+      methodType: 'server_streaming',
+      response: resObj,
+      type: '__GRPCWEB_DEVTOOLS__',
+    },
+    '*',
+  );
+}
+
+function logStreamingRequestMessage<T>(request: T, path: string) {
+  const reqObj = getAsObject(request);
+  window.postMessage(
+    {
+      method: path,
+      methodType: 'server_streaming',
+      request: reqObj,
+      type: '__GRPCWEB_DEVTOOLS__',
+    },
+    '*',
+  );
+}