Returning rejected promises in HttpConnection

src/SignalR/clients/ts/signalr/src/HttpConnection.ts

@@ -115,7 +115,7 @@ export class HttpConnection implements IConnection {
 
     public send(data: string | ArrayBuffer): Promise<void> {
         if (this.connectionState !== ConnectionState.Connected) {
-            throw new Error("Cannot send data if the connection is not in the 'Connected' State.");
+            return Promise.reject(new Error("Cannot send data if the connection is not in the 'Connected' State."));
         }
 
         // Transport will not be null if state is connected
@@ -157,7 +157,7 @@ export class HttpConnection implements IConnection {
                     // No fallback or negotiate in this case.
                     await this.transport!.connect(url, transferFormat);
                 } else {
-                    throw Error("Negotiation can only be skipped when using the WebSocket transport directly.");
+                    return Promise.reject(new Error("Negotiation can only be skipped when using the WebSocket transport directly."));
                 }
             } else {
                 let negotiateResponse: INegotiateResponse | null = null;
@@ -171,11 +171,11 @@ export class HttpConnection implements IConnection {
                     }
 
                     if (negotiateResponse.error) {
-                        throw Error(negotiateResponse.error);
+                        return Promise.reject(new Error(negotiateResponse.error));
                     }
 
                     if ((negotiateResponse as any).ProtocolVersion) {
-                        throw Error("Detected a connection attempt to an ASP.NET SignalR Server. This client only supports connecting to an ASP.NET Core SignalR Server. See https://aka.ms/signalr-core-differences for details.");
+                        return Promise.reject(new Error("Detected a connection attempt to an ASP.NET SignalR Server. This client only supports connecting to an ASP.NET Core SignalR Server. See https://aka.ms/signalr-core-differences for details."));
                     }
 
                     if (negotiateResponse.url) {
@@ -194,7 +194,7 @@ export class HttpConnection implements IConnection {
                 while (negotiateResponse.url && redirects < MAX_REDIRECTS);
 
                 if (redirects === MAX_REDIRECTS && negotiateResponse.url) {
-                    throw Error("Negotiate redirection limit exceeded.");
+                    return Promise.reject(new Error("Negotiate redirection limit exceeded."));
                 }
 
                 await this.createTransport(url, this.options.transport, negotiateResponse, transferFormat);
@@ -214,7 +214,7 @@ export class HttpConnection implements IConnection {
             this.logger.log(LogLevel.Error, "Failed to start the connection: " + e);
             this.connectionState = ConnectionState.Disconnected;
             this.transport = undefined;
-            throw e;
+            return Promise.reject(e);
         }
     }
 
@@ -238,13 +238,13 @@ export class HttpConnection implements IConnection {
             });
 
             if (response.statusCode !== 200) {
-                throw Error(`Unexpected status code returned from negotiate ${response.statusCode}`);
+                return Promise.reject(new Error(`Unexpected status code returned from negotiate ${response.statusCode}`));
             }
 
             return JSON.parse(response.content as string) as INegotiateResponse;
         } catch (e) {
             this.logger.log(LogLevel.Error, "Failed to complete negotiation with the server: " + e);
-            throw e;
+            return Promise.reject(e);
         }
     }
 
@@ -293,9 +293,9 @@ export class HttpConnection implements IConnection {
         }
 
         if (transportExceptions.length > 0) {
-            throw new Error(`Unable to connect to the server with any of the available transports. ${transportExceptions.join(" ")}`);
+            return Promise.reject(new Error(`Unable to connect to the server with any of the available transports. ${transportExceptions.join(" ")}`));
         }
-        throw new Error("None of the transports supported by the client are supported by the server.");
+        return Promise.reject(new Error("None of the transports supported by the client are supported by the server."));
     }
 
     private constructTransport(transport: HttpTransportType) {

src/SignalR/clients/ts/signalr/tests/HttpConnection.test.ts

@@ -150,6 +150,72 @@ describe("HttpConnection", () => {
         });
     });
 
+    it("cannot send with an un-started connection", async () => {
+        await VerifyLogger.run(async (logger) => {
+            const connection = new HttpConnection("http://tempuri.org");
+
+            await expect(connection.send("LeBron James"))
+                .rejects
+                .toThrow("Cannot send data if the connection is not in the 'Connected' State.");
+        });
+    });
+
+    it("sending before start doesn't throw synchronously", async () => {
+        await VerifyLogger.run(async (logger) => {
+            const connection = new HttpConnection("http://tempuri.org");
+
+            try {
+                connection.send("test").catch((e) => {});
+            } catch (e) {
+                expect(false).toBe(true);
+            }
+
+        });
+    });
+
+    it("cannot be started if negotiate returns non 200 response", async () => {
+        await VerifyLogger.run(async (logger) => {
+            const options: IHttpConnectionOptions = {
+                ...commonOptions,
+                httpClient: new TestHttpClient()
+                    .on("POST", () => new HttpResponse(999))
+                    .on("GET", () => ""),
+                logger,
+            } as IHttpConnectionOptions;
+
+            const connection = new HttpConnection("http://tempuri.org", options);
+            await expect(connection.start(TransferFormat.Text))
+                .rejects
+                .toThrow("Unexpected status code returned from negotiate 999");
+        },
+        "Failed to start the connection: Error: Unexpected status code returned from negotiate 999");
+    });
+
+    it("all transport failure error get aggregated", async () => {
+        await VerifyLogger.run(async (loggerImpl) => {
+            const options: IHttpConnectionOptions = {
+                WebSocket: false,
+                ...commonOptions,
+                httpClient: new TestHttpClient()
+                    .on("POST", () => defaultNegotiateResponse)
+                    .on("GET", () => new HttpResponse(200))
+                    .on("DELETE", () => new HttpResponse(202)),
+
+                logger: loggerImpl,
+                transport: HttpTransportType.WebSockets,
+            } as IHttpConnectionOptions;
+
+            const connection = new HttpConnection("http://tempuri.org", options);
+            await expect(connection.start(TransferFormat.Text))
+                .rejects
+                .toThrow("Unable to connect to the server with any of the available transports. WebSockets failed: null ServerSentEvents failed: Error: 'ServerSentEvents' is disabled by the client. LongPolling failed: Error: 'LongPolling' is disabled by the client.");
+        },
+        "Failed to start the transport 'WebSockets': null",
+        "Failed to start the transport 'ServerSentEvents': Error: 'ServerSentEvents' is disabled by the client.",
+        "Failed to start the transport 'LongPolling': Error: 'LongPolling' is disabled by the client.",
+        "Failed to start the connection: Error: Unable to connect to the server with any of the available transports. WebSockets failed: null ServerSentEvents failed: Error: 'ServerSentEvents' is disabled by the client. LongPolling failed: Error: 'LongPolling' is disabled by the client.");
+    });
+
     it("can stop a non-started connection", async () => {
         await VerifyLogger.run(async (logger) => {
             const connection = new HttpConnection("http://tempuri.org", { ...commonOptions, logger });