(maint) ensure unbuffered-stream correctly handles 204 responses

CHANGELOG.md

@@ -1,5 +1,8 @@
 ## Unreleased
 
+# 2.1.3
+* ensure unbuffered-stream correctly handles 204 responses with no body in the response.
+
 # 2.1.2
 * add support for multiple `Set-Cookie` headers in a response separated by newlines. 
 * update project.clj to remove composite profiles that include maps, it is deprecated in lein 2.11.0

src/java/com/puppetlabs/http/client/impl/StreamingAsyncResponseConsumer.java

@@ -1,10 +1,13 @@
 package com.puppetlabs.http.client.impl;
 
+import org.apache.http.HttpEntity;
 import org.apache.http.HttpResponse;
 import org.apache.http.entity.BasicHttpEntity;
 import org.apache.http.nio.IOControl;
 import org.apache.http.nio.client.methods.AsyncByteConsumer;
 import org.apache.http.protocol.HttpContext;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.io.IOException;
 import java.io.PipedInputStream;
@@ -18,6 +21,8 @@ public class StreamingAsyncResponseConsumer extends AsyncByteConsumer<HttpRespon
     private volatile Deliverable<HttpResponse> promise;
     private volatile Promise<IOException> ioExceptionPromise = new Promise<>();
 
+    private static final Logger LOGGER = LoggerFactory.getLogger(StreamingAsyncResponseConsumer.class);
+
     public void setFinalResult(IOException ioException) {
         ioExceptionPromise.deliver(ioException);
     }
@@ -28,10 +33,16 @@ public StreamingAsyncResponseConsumer(Deliverable<HttpResponse> promise) {
 
     @Override
     protected void onResponseReceived(final HttpResponse response) throws IOException {
-        PipedInputStream pis = new ExceptionInsertingPipedInputStream(ioExceptionPromise);
-        pos = new PipedOutputStream();
-        pos.connect(pis);
-        ((BasicHttpEntity) response.getEntity()).setContent(pis);
+        HttpEntity entity = response.getEntity();
+        if (entity != null) {
+            PipedInputStream pis = new ExceptionInsertingPipedInputStream(ioExceptionPromise);
+            pos = new PipedOutputStream();
+            pos.connect(pis);
+            ((BasicHttpEntity) entity).setContent(pis);
+        } else {
+            // this can happen if the server sends no response, like with a 204.
+            LOGGER.debug("Null entity when processing response");
+        }
         this.response = response;
         promise.deliver(response);
     }

test/puppetlabs/http/client/async_unbuffered_test.clj

@@ -324,3 +324,13 @@
 (deftest java-existing-streaming-with-large-payload-with-decompression
   (testing "java :stream with 1M payload and decompression"
     (java-blocking-streaming (generate-data (* 1024 1024)) ResponseBodyType/STREAM true)))
+
+(deftest java-204-streaming
+  (testing "client handles a webserver that returns a 204 response and no body correctly"
+    (testwebserver/with-test-webserver-and-config
+      (constantly {:status 204}) port {:shutdown-timeout-seconds 1}
+      (with-open [client (async/create-client {:connect-timeout-milliseconds 100})]
+        (let [response @(common/post client (str "http://localhost:" port "/something") {:method :post
+                                                                                         :as :unbuffered-stream})]
+          (is (= 204 (:status response))))))))
+