Support overriding content type via explicit header.

okhttp-apache/pom.xml

@@ -18,12 +18,6 @@
       <artifactId>okhttp</artifactId>
       <version>${project.version}</version>
     </dependency>
-    <dependency>
-      <groupId>com.squareup.okhttp</groupId>
-      <artifactId>mockwebserver</artifactId>
-      <version>${project.version}</version>
-      <scope>test</scope>
-    </dependency>
     <dependency>
       <groupId>org.apache.httpcomponents</groupId>
       <artifactId>httpclient</artifactId>
@@ -35,6 +29,12 @@
       <artifactId>junit</artifactId>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>com.squareup.okhttp</groupId>
+      <artifactId>mockwebserver</artifactId>
+      <version>${project.version}</version>
+      <scope>test</scope>
+    </dependency>
   </dependencies>
 
   <build>

okhttp-apache/src/main/java/com/squareup/okhttp/apache/HttpEntityBody.java

@@ -4,23 +4,27 @@
 import com.squareup.okhttp.RequestBody;
 import java.io.IOException;
 import okio.BufferedSink;
-import org.apache.http.Header;
 import org.apache.http.HttpEntity;
 
 /** Adapts an {@link HttpEntity} to OkHttp's {@link RequestBody}. */
 final class HttpEntityBody extends RequestBody {
-  private static final String DEFAULT_MEDIA_TYPE = "application/octet-stream";
+  private static final MediaType DEFAULT_MEDIA_TYPE = MediaType.parse("application/octet-stream");
 
   private final HttpEntity entity;
   private final MediaType mediaType;
 
-  HttpEntityBody(HttpEntity entity) {
+  HttpEntityBody(HttpEntity entity, String contentTypeHeader) {
     this.entity = entity;
 
-    // Apache is forgiving and lets you skip specifying a content type with an entity. OkHttp is
-    // not forgiving so we fall back to a generic type if it's missing.
-    Header contentType = entity.getContentType();
-    mediaType = MediaType.parse(contentType != null ? contentType.getValue() : DEFAULT_MEDIA_TYPE);
+    if (contentTypeHeader != null) {
+      mediaType = MediaType.parse(contentTypeHeader);
+    } else if (entity.getContentType() != null) {
+      mediaType = MediaType.parse(entity.getContentType().getValue());
+    } else {
+      // Apache is forgiving and lets you skip specifying a content type with an entity. OkHttp is
+      // not forgiving so we fall back to a generic type if it's missing.
+      mediaType = DEFAULT_MEDIA_TYPE;
+    }
   }
 
   @Override public long contentLength() {

okhttp-apache/src/main/java/com/squareup/okhttp/apache/OkApacheClient.java

@@ -46,16 +46,22 @@ private static Request transformRequest(HttpRequest request) {
     String method = requestLine.getMethod();
     builder.url(requestLine.getUri());
 
+    String contentType = null;
     for (Header header : request.getAllHeaders()) {
-      builder.header(header.getName(), header.getValue());
+      String name = header.getName();
+      if ("Content-Type".equals(name)) {
+        contentType = header.getValue();
+      } else {
+        builder.header(name, header.getValue());
+      }
     }
 
     RequestBody body = null;
     if (request instanceof HttpEntityEnclosingRequest) {
       HttpEntity entity = ((HttpEntityEnclosingRequest) request).getEntity();
       if (entity != null) {
         // Wrap the entity in a custom Body which takes care of the content, length, and type.
-        body = new HttpEntityBody(entity);
+        body = new HttpEntityBody(entity, contentType);
 
         Header encoding = entity.getContentEncoding();
         if (encoding != null) {

okhttp-apache/src/test/java/com/squareup/okhttp/apache/OkApacheClientTest.java

@@ -18,6 +18,7 @@
 import org.apache.http.client.methods.HttpPost;
 import org.apache.http.entity.ByteArrayEntity;
 import org.apache.http.entity.InputStreamEntity;
+import org.apache.http.entity.StringEntity;
 import org.apache.http.util.EntityUtils;
 import org.junit.After;
 import org.junit.Before;
@@ -114,6 +115,19 @@ public class OkApacheClientTest {
     assertEquals(request.getHeader("Content-Length"), "13");
   }
 
+  @Test public void postOverrideContentType() throws Exception {
+    server.enqueue(new MockResponse());
+
+    HttpPost httpPost = new HttpPost();
+    httpPost.setURI(server.getUrl("/").toURI());
+    httpPost.addHeader("Content-Type", "application/xml");
+    httpPost.setEntity(new StringEntity("<yo/>"));
+    client.execute(httpPost);
+
+    RecordedRequest request = server.takeRequest();
+    assertEquals(request.getHeader("Content-Type"), "application/xml");
+  }
+
   @Test public void contentType() throws Exception {
     server.enqueue(new MockResponse().setBody("<html><body><h1>Hello, World!</h1></body></html>")
         .setHeader("Content-Type", "text/html"));