enable streaming and ensure pass-through content-length header if available

Author: stefanseifert

maven-nodejs-proxy/src/main/java/io/wcm/devops/maven/nodejsproxy/resource/MavenProxyResource.java

@@ -19,6 +19,7 @@
  */
 package io.wcm.devops.maven.nodejsproxy.resource;
 
+import static javax.ws.rs.core.HttpHeaders.CONTENT_LENGTH;
 import io.wcm.devops.maven.nodejsproxy.MavenProxyConfiguration;
 
 import java.io.IOException;
@@ -187,19 +188,15 @@ public Response getBinary(
       log.info("Proxy file: {}", url);
       HttpGet get = new HttpGet(url);
       HttpResponse response = httpClient.execute(get);
-      try {
-        if (response.getStatusLine().getStatusCode() == HttpServletResponse.SC_OK) {
-          byte[] data = EntityUtils.toByteArray(response.getEntity());
-          return Response.ok(data)
-              .type(MediaType.APPLICATION_OCTET_STREAM)
-              .build();
-        }
-        else {
-          return Response.status(Response.Status.NOT_FOUND).build();
-        }
+      if (response.getStatusLine().getStatusCode() == HttpServletResponse.SC_OK) {
+        return Response.ok(new SpoolStreamingOutput(response.getEntity()))
+            .type(MediaType.APPLICATION_OCTET_STREAM)
+            .header(CONTENT_LENGTH, response.containsHeader(CONTENT_LENGTH) ? response.getFirstHeader(CONTENT_LENGTH).getValue() : null)
+            .build();
       }
-      finally {
+      else {
         EntityUtils.consumeQuietly(response.getEntity());
+        return Response.status(Response.Status.NOT_FOUND).build();
       }
     }
   }
@@ -242,26 +239,24 @@ public Response getBinary(
     log.info("Proxy file: {}", url);
     HttpGet get = new HttpGet(url);
     HttpResponse response = httpClient.execute(get);
-    try {
-      if (response.getStatusLine().getStatusCode() == HttpServletResponse.SC_OK) {
+    if (response.getStatusLine().getStatusCode() == HttpServletResponse.SC_OK) {
+      if (getChecksum) {
         byte[] data = EntityUtils.toByteArray(response.getEntity());
-        if (getChecksum) {
-          return Response.ok(DigestUtils.sha1Hex(data))
-              .type(MediaType.TEXT_PLAIN)
-              .build();
-        }
-        else {
-          return Response.ok(data)
-              .type(MediaType.APPLICATION_OCTET_STREAM)
-              .build();
-        }
+        EntityUtils.consumeQuietly(response.getEntity());
+        return Response.ok(DigestUtils.sha1Hex(data))
+            .type(MediaType.TEXT_PLAIN)
+            .build();
       }
       else {
-        return Response.status(Response.Status.NOT_FOUND).build();
+        return Response.ok(new SpoolStreamingOutput(response.getEntity()))
+            .type(MediaType.APPLICATION_OCTET_STREAM)
+            .header(CONTENT_LENGTH, response.containsHeader(CONTENT_LENGTH) ? response.getFirstHeader(CONTENT_LENGTH).getValue() : null)
+            .build();
       }
     }
-    finally {
+    else {
       EntityUtils.consumeQuietly(response.getEntity());
+      return Response.status(Response.Status.NOT_FOUND).build();
     }
   }
 

maven-nodejs-proxy/src/main/java/io/wcm/devops/maven/nodejsproxy/resource/SpoolStreamingOutput.java

@@ -0,0 +1,54 @@
+/*
+ * #%L
+ * wcm.io
+ * %%
+ * Copyright (C) 2015 wcm.io
+ * %%
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * #L%
+ */
+package io.wcm.devops.maven.nodejsproxy.resource;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+import javax.ws.rs.WebApplicationException;
+import javax.ws.rs.core.StreamingOutput;
+
+import org.apache.commons.io.IOUtils;
+import org.apache.http.HttpEntity;
+import org.apache.http.util.EntityUtils;
+
+/**
+ * Spool binary data from HTTP response to JAX-RS output.
+ */
+class SpoolStreamingOutput implements StreamingOutput {
+
+  private final HttpEntity httpEntity;
+
+  public SpoolStreamingOutput(HttpEntity httpEntity) {
+    this.httpEntity = httpEntity;
+  }
+
+  @Override
+  public void write(OutputStream os) throws IOException, WebApplicationException {
+    try (InputStream is = httpEntity.getContent()) {
+      IOUtils.copyLarge(is, os);
+    }
+    finally {
+      EntityUtils.consumeQuietly(httpEntity);
+    }
+  }
+
+}