Enable UrlConnection http client chunked encoding (#4207)

* Fix chunked-encoding in UrlConnection client

* Verify payload in test

Author: davidh44

http-clients/url-connection-client/src/main/java/software/amazon/awssdk/http/urlconnection/UrlConnectionHttpClient.java

@@ -154,6 +154,11 @@ private HttpURLConnection createAndConfigureConnection(HttpExecuteRequest reques
         HttpURLConnection connection = connectionFactory.createConnection(sdkHttpRequest.getUri());
         sdkHttpRequest.forEachHeader((key, values) -> values.forEach(value -> connection.setRequestProperty(key, value)));
 
+        // connection.setRequestProperty("Transfer-Encoding", "chunked") does not work, i.e., property does not get set
+        if (sdkHttpRequest.matchingHeaders("Transfer-Encoding").contains("chunked")) {
+            connection.setChunkedStreamingMode(-1);
+        }
+
         if (!sdkHttpRequest.firstMatchingHeader(ACCEPT).isPresent()) {
             // Override Accept header because the default one in JDK does not comply with RFC 7231
             // See: https://bugs.openjdk.org/browse/JDK-8163921

http-clients/url-connection-client/src/test/java/software/amazon/awssdk/http/urlconnection/UrlConnectionHttpClientWireMockTest.java

@@ -18,6 +18,8 @@
 import static com.github.tomakehurst.wiremock.client.WireMock.postRequestedFor;
 import static com.github.tomakehurst.wiremock.client.WireMock.urlPathEqualTo;
 import static software.amazon.awssdk.http.Header.ACCEPT;
+import static software.amazon.awssdk.http.Header.CHUNKED;
+import static software.amazon.awssdk.http.Header.TRANSFER_ENCODING;
 import static software.amazon.awssdk.http.SdkHttpConfigurationOption.TRUST_ALL_CERTIFICATES;
 
 import java.io.IOException;
@@ -92,6 +94,25 @@ public void hasAcceptHeader_shouldNotOverride() throws IOException {
         mockServer.verify(postRequestedFor(urlPathEqualTo("/")).withHeader(ACCEPT, equalTo("text/html")));
     }
 
+    @Test
+    public void hasTransferEncodingHeader_shouldBeSet() throws IOException {
+        SdkHttpClient client = createSdkHttpClient();
+
+        stubForMockRequest(200);
+
+        SdkHttpFullRequest req = mockSdkRequest("http://localhost:" + mockServer.port(), SdkHttpMethod.POST);
+        req = req.toBuilder().putHeader(TRANSFER_ENCODING, CHUNKED).build();
+        HttpExecuteResponse rsp = client.prepareRequest(HttpExecuteRequest.builder()
+                                                                          .request(req)
+                                                                          .contentStreamProvider(req.contentStreamProvider()
+                                                                                                    .orElse(null))
+                                                                          .build())
+                                        .call();
+
+        mockServer.verify(postRequestedFor(urlPathEqualTo("/")).withHeader(TRANSFER_ENCODING, equalTo(CHUNKED)));
+        mockServer.verify(postRequestedFor(urlPathEqualTo("/")).withRequestBody(equalTo("Body")));
+    }
+
 
     @After
     public void reset() {