support PUT with empty body parameter

follow-up commit to https://github.com/Netflix/feign/pull/271

CHANGELOG.md

@@ -1,3 +1,6 @@
+### Version 8.15
+* Supports PUT without a body parameter
+
 ### Version 8.14
 * Add support for RxJava Observable and Single return types via the `HystrixFeign` builder.
 * Adds fallback implementation configuration to the `HystrixFeign` builder

core/src/test/java/feign/client/DefaultClientTest.java

@@ -184,7 +184,7 @@ public class DefaultClientTest {
   }
 
   @Test
-  public void noResponseBody() {
+  public void noResponseBodyForPost() {
       server.enqueue(new MockResponse());
 
       TestInterface api = Feign.builder()
@@ -192,6 +192,16 @@ public class DefaultClientTest {
 
       api.noPostBody();
   }
+  
+  @Test
+  public void noResponseBodyForPut() {
+      server.enqueue(new MockResponse());
+      
+      TestInterface api = Feign.builder()
+              .target(TestInterface.class, "http://localhost:" + server.getPort());
+      
+      api.noPutBody();
+  }
 
   interface TestInterface {
 
@@ -209,5 +219,8 @@ public class DefaultClientTest {
 
     @RequestLine("POST")
     String noPostBody();
+    
+    @RequestLine("PUT")
+    String noPutBody();
   }
 }

httpclient/src/test/java/feign/httpclient/ApacheHttpClientTest.java

@@ -136,7 +136,7 @@ public class ApacheHttpClientTest {
   }
 
   @Test
-  public void noResponseBody() {
+  public void noResponseBodyForPost() {
       server.enqueue(new MockResponse());
 
       TestInterface api = Feign.builder()
@@ -145,6 +145,17 @@ public class ApacheHttpClientTest {
 
       api.noPostBody();
   }
+  
+  @Test
+  public void noResponseBodyForPut() {
+      server.enqueue(new MockResponse());
+      
+      TestInterface api = Feign.builder()
+              .client(new ApacheHttpClient())
+              .target(TestInterface.class, "http://localhost:" + server.getPort());
+      
+      api.noPutBody();
+  }
     @Test
     public void postWithSpacesInPath() throws IOException, InterruptedException {
         server.enqueue(new MockResponse().setBody("foo"));
@@ -176,6 +187,9 @@ public class ApacheHttpClientTest {
 
     @RequestLine("POST")
     String noPostBody();
+    
+    @RequestLine("PUT")
+    String noPutBody();
 
     @RequestLine("POST /path/{to}/resource")
     @Headers("Accept: text/plain")

okhttp/src/main/java/feign/okhttp/OkHttpClient.java

@@ -79,7 +79,8 @@ public final class OkHttpClient implements Client {
     }
 
     byte[] inputBody = input.body();
-    if ("POST".equals(input.method()) && inputBody == null) {
+    boolean isMethodWithBody = "POST".equals(input.method()) || "PUT".equals(input.method());
+    if (isMethodWithBody && inputBody == null) {
       // write an empty BODY to conform with okhttp 2.4.0+
       // http://johnfeng.github.io/blog/2015/06/30/okhttp-updates-post-wouldnt-be-allowed-to-have-null-body/
       inputBody = new byte[0];

okhttp/src/test/java/feign/okhttp/OkHttpClientTest.java

@@ -135,7 +135,7 @@ public class OkHttpClientTest {
   }
 
   @Test
-  public void noResponseBody() {
+  public void noResponseBodyForPost() {
       server.enqueue(new MockResponse());
 
       TestInterface api = Feign.builder()
@@ -144,6 +144,17 @@ public class OkHttpClientTest {
 
       api.noPostBody();
   }
+  
+  @Test
+  public void noResponseBodyForPut() {
+      server.enqueue(new MockResponse());
+      
+      TestInterface api = Feign.builder()
+              .client(new OkHttpClient())
+              .target(TestInterface.class, "http://localhost:" + server.getPort());
+      
+      api.noPutBody();
+  }
 
   interface TestInterface {
 
@@ -161,5 +172,8 @@ public class OkHttpClientTest {
 
     @RequestLine("POST")
     String noPostBody();
+    
+    @RequestLine("PUT")
+    String noPutBody();
   }
 }