Remove support for streaming responses for v1 callables.

spec/common/providers/https.spec.ts

@@ -802,6 +802,26 @@
       const data = [`data: {"error":{"message":"INTERNAL","status":"INTERNAL"}}`];
       expect(resp.body).to.equal([...data, ""].join("\n"));
     });
+
+    it("always returns error for v1 callables", async () => {
+      const mockReq = mockRequest(
+        { message: "hello streaming" },
+        "application/json",
+        {},
+        { accept: "text/event-stream" }
+      ) as any;
+      const fn = https.onCallHandler(
+        {
+          cors: { origin: true, methods: "POST" },
+        },
+        (req, resp) => {
+          return "hello world";
+        },
+        "gcfv1"
+      );
+      const resp = await runHandler(fn, mockReq);
+      expect(JSON.parse(resp.body)).to.deep.equal({ "error": { "status": "INVALID_ARGUMENT", "message": "Unsupported Accept header 'text/event-stream'" } });
+    });
   });
 });
 

src/common/providers/https.ts

@@ -782,6 +782,12 @@
       }
 
       const acceptsStreaming = req.header("accept") === "text/event-stream";
+
+      if (acceptsStreaming && version === "gcfv1") {
+        // streaming responses are not supported in v1 callable
+        throw new HttpsError('invalid-argument', "Unsupported Accept header 'text/event-stream'")
+      }
+
       const data: Req = decode(req.body.data);
       let result: Res;
       if (version === "gcfv1") {
@@ -832,11 +838,11 @@
 
       const { status } = httpErr.httpErrorCode;
       const body = { error: httpErr.toJSON() };
-      if (req.header("accept") === "text/event-stream") {
+      if (version === "gcfv2" && req.header("accept") === "text/event-stream") {
         res.send(encodeSSE(body));
       } else {
         res.status(status).send(body);
       }
     }
-  };
-}
+  }
+};