Allow an HTTP client request to have a null authority.

Motivation:

In some cases it is desirable to send an HTTP request that does not carry the http2 pseudo authority header, nor the host header.

Author: vietj

vertx-core/src/main/java/io/vertx/core/http/impl/Http1xClientConnection.java

@@ -187,7 +187,9 @@ private HttpRequest createRequest(
       }
     }
     if (!headers.contains(HOST)) {
-      request.headers().set(HOST, authority.toString(ssl));
+      if (authority != null) {
+        request.headers().set(HOST, authority.toString(ssl));
+      }
     } else {
       headers.remove(TRANSFER_ENCODING);
     }

vertx-core/src/main/java/io/vertx/core/http/impl/HttpClientRequestBase.java

@@ -117,7 +117,6 @@ public synchronized HttpClientRequest setURI(String uri) {
 
   @Override
   public synchronized HttpClientRequest authority(HostAndPort authority) {
-    Objects.requireNonNull(authority);
     this.authority = authority;
     return this;
   }

vertx-core/src/test/java/io/vertx/tests/http/Http1xTest.java

@@ -5431,7 +5431,7 @@ private void testEmptyHostPortionOfHostHeader(String hostHeader, int expectedPor
   }
 
   @Test
-  public void testMissingHostHeader() throws Exception {
+  public void testServerMissingHostHeader() throws Exception {
     server.requestHandler(req -> {
       assertEquals(null, req.authority());
       assertFalse(((HttpServerRequestInternal) req).isValidAuthority());
@@ -5445,6 +5445,23 @@ public void testMissingHostHeader() throws Exception {
     await();
   }
 
+  @Test
+  public void testClientMissingHostHeader() throws Exception {
+    server.requestHandler(req -> {
+      assertEquals(null, req.authority());
+      assertFalse(((HttpServerRequestInternal) req).isValidAuthority());
+      req.response().end();
+    });
+    startServer(testAddress);
+    client.request(requestOptions)
+      .compose(request -> request
+        .authority(null)
+        .send()
+        .expecting(HttpResponseExpectation.SC_OK)
+        .compose(HttpClientResponse::end))
+      .await();
+  }
+
   @Test
   public void testCanUpgradeToWebSocket() throws Exception {
     UnaryOperator<RequestOptions> config = ro -> ro.setMethod(HttpMethod.GET)

vertx-core/src/test/java/io/vertx/tests/http/Http2ClientTest.java

@@ -378,6 +378,31 @@ public void testOverrideAuthority() throws Exception {
     await();
   }
 
+  @Test
+  public void testNoAuthority() throws Exception {
+    ServerBootstrap bootstrap = createH2Server((decoder, encoder) -> new Http2EventAdapter() {
+      @Override
+      public void onHeadersRead(ChannelHandlerContext ctx, int streamId, Http2Headers headers, int streamDependency, short weight, boolean exclusive, int padding, boolean endStream) throws Http2Exception {
+        vertx.runOnContext(v -> {
+          assertNull(headers.authority());
+          encoder.writeHeaders(ctx, streamId, new DefaultHttp2Headers().status("200"), 0, true, ctx.newPromise());
+          ctx.flush();
+        });
+      }
+    });
+    ChannelFuture s = bootstrap.bind(DEFAULT_HTTPS_HOST, DEFAULT_HTTPS_PORT).sync();
+    client.request(new RequestOptions().setServer(testAddress)
+        .setPort(4444)
+        .setHost("localhost")
+      )
+      .compose(request -> {
+        request.authority(null);
+        return request.send();
+      })
+      .onComplete(onSuccess(resp -> testComplete()));
+    await();
+  }
+
   @Test
   public void testTrailers() throws Exception {
     server.requestHandler(req -> {