[Java] Add ability to configure headers (#3090)

clients/java/signalr/src/main/java/com/microsoft/signalr/HttpHubConnectionBuilder.java

@@ -4,6 +4,8 @@
 package com.microsoft.signalr;
 
 import java.time.Duration;
+import java.util.HashMap;
+import java.util.Map;
 
 import io.reactivex.Single;
 
@@ -15,6 +17,7 @@ public class HttpHubConnectionBuilder {
     private boolean skipNegotiate;
     private Single<String> accessTokenProvider;
     private Duration handshakeResponseTimeout;
+    private Map<String, String> headers;
 
     HttpHubConnectionBuilder(String url) {
         this.url = url;
@@ -61,7 +64,20 @@ public class HttpHubConnectionBuilder {
         return this;
     }
 
+    public HttpHubConnectionBuilder withHeaders(Map<String, String> headers) {
+        this.headers = headers;
+        return this;
+    }
+
+    public HttpHubConnectionBuilder withHeader(String name, String value) {
+        if (headers == null) {
+            this.headers = new HashMap<>();
+        }
+        this.headers.put(name, value);
+        return this;
+    }
+
     public HubConnection build() {
-        return new HubConnection(url, transport, skipNegotiate, logger, httpClient, accessTokenProvider, handshakeResponseTimeout);
+        return new HubConnection(url, transport, skipNegotiate, logger, httpClient, accessTokenProvider, handshakeResponseTimeout, headers);
     }
 }

clients/java/signalr/src/main/java/com/microsoft/signalr/HubConnection.java

@@ -72,7 +72,8 @@ public class HubConnection {
         this.tickRate = tickRate;
     }
 
-    HubConnection(String url, Transport transport, boolean skipNegotiate, Logger logger, HttpClient httpClient, Single<String> accessTokenProvider, Duration handshakeResponseTimeout) {
+    HubConnection(String url, Transport transport, boolean skipNegotiate, Logger logger, HttpClient httpClient,
+                  Single<String> accessTokenProvider, Duration handshakeResponseTimeout, Map<String, String> headers) {
         if (url == null || url.isEmpty()) {
             throw new IllegalArgumentException("A valid url is required.");
         }
@@ -106,6 +107,10 @@ public class HubConnection {
             this.handshakeResponseTimeout = handshakeResponseTimeout;
         }
 
+        if (headers != null) {
+            this.headers.putAll(headers);
+        }
+
         this.skipNegotiate = skipNegotiate;
 
         this.callback = (payload) -> {

clients/java/signalr/src/test/java/com/microsoft/signalr/HubConnectionTest.java

@@ -1037,7 +1037,7 @@ class HubConnectionTest {
     }
 
     @Test
-    public void accessTokenProviderIsOverriddenFromRedirectNegotiate()  {
+    public void accessTokenProviderIsOverriddenFromRedirectNegotiate() {
         AtomicReference<String> token = new AtomicReference<>();
         TestHttpClient client = new TestHttpClient()
             .on("POST", "http://example.com/negotiate", (req) -> CompletableFuture.completedFuture(new HttpResponse(200, "", "{\"url\":\"http://testexample.com/\",\"accessToken\":\"newToken\"}")))
@@ -1098,7 +1098,60 @@ class HubConnectionTest {
     }
 
     @Test
-    public void hubConnectionCanBeStartedAfterBeingStopped()  {
+    public void headersAreSetAndSentThroughBuilder() {
+        AtomicReference<String> header = new AtomicReference<>();
+        TestHttpClient client = new TestHttpClient()
+                .on("POST", "http://example.com/negotiate",
+                        (req) -> {
+                            header.set(req.getHeaders().get("ExampleHeader"));
+                            return CompletableFuture
+                                    .completedFuture(new HttpResponse(200, "", "{\"connectionId\":\"bVOiRPG8-6YiJ6d7ZcTOVQ\",\""
+                                            + "availableTransports\":[{\"transport\":\"WebSockets\",\"transferFormats\":[\"Text\",\"Binary\"]}]}"));
+                        });
+
+
+        MockTransport transport = new MockTransport();
+        HubConnection hubConnection = HubConnectionBuilder.create("http://example.com")
+                .withTransport(transport)
+                .withHttpClient(client)
+                .withHeader("ExampleHeader", "ExampleValue")
+                .build();
+
+        hubConnection.start().blockingAwait(1000, TimeUnit.MILLISECONDS);
+        assertEquals(HubConnectionState.CONNECTED, hubConnection.getConnectionState());
+        hubConnection.stop();
+        assertEquals("ExampleValue", header.get());
+    }
+
+    @Test
+    public void sameHeaderSetTwiceGetsOverwritten() {
+        AtomicReference<String> header = new AtomicReference<>();
+        TestHttpClient client = new TestHttpClient()
+                .on("POST", "http://example.com/negotiate",
+                        (req) -> {
+                            header.set(req.getHeaders().get("ExampleHeader"));
+                            return CompletableFuture
+                                    .completedFuture(new HttpResponse(200, "", "{\"connectionId\":\"bVOiRPG8-6YiJ6d7ZcTOVQ\",\""
+                                            + "availableTransports\":[{\"transport\":\"WebSockets\",\"transferFormats\":[\"Text\",\"Binary\"]}]}"));
+                        });
+
+
+        MockTransport transport = new MockTransport();
+        HubConnection hubConnection = HubConnectionBuilder.create("http://example.com")
+                .withTransport(transport)
+                .withHttpClient(client)
+                .withHeader("ExampleHeader", "ExampleValue")
+                .withHeader("ExampleHeader", "New Value")
+                .build();
+
+        hubConnection.start().blockingAwait(1000, TimeUnit.MILLISECONDS);
+        assertEquals(HubConnectionState.CONNECTED, hubConnection.getConnectionState());
+        hubConnection.stop();
+        assertEquals("New Value", header.get());
+    }
+
+    @Test
+    public void hubConnectionCanBeStartedAfterBeingStopped() throws Exception {
         MockTransport transport = new MockTransport();
         HubConnection hubConnection = HubConnectionBuilder
                 .create("http://example.com")

clients/java/signalr/src/test/java/com/microsoft/signalr/NegotiateResponseTest.java

@@ -5,8 +5,6 @@ package com.microsoft.signalr;
 
 import static org.junit.jupiter.api.Assertions.*;
 
-import java.io.IOException;
-
 import org.junit.jupiter.api.Test;