Raise an error if multipart/@media-type conflicts with Content-Type header

Closes #39

Author: adamretter

http-client-java/src/main/java/org/expath/httpclient/HttpClientError.java

@@ -23,7 +23,8 @@ public enum HttpClientError implements ExpathError {
   HC003("HC003", "With a multipart response, the override-media-type must be either a multipart media type or application/octet-stream."),
   HC004("HC004", "The src attribute on the body element is mutually exclusive with all other attribute (except the media-type)."),
   HC005("HC005", "The request element is not valid."),
-  HC006("HC006", "A timeout occurred waiting for the response.");
+  HC006("HC006", "A timeout occurred waiting for the response."),
+  HC007("HC007", "Multipart @media-type conflicts with outer Content-Type header");
 
   private final QName name;
   private final String description;

http-client-java/src/main/java/org/expath/httpclient/impl/MultipartRequestBody.java

@@ -14,11 +14,19 @@
 import java.util.ArrayList;
 import java.util.List;
 import org.apache.http.Header;
-import org.expath.httpclient.*;
+import org.apache.http.message.BasicHeader;
+import org.expath.httpclient.ContentType;
+import org.expath.httpclient.HeaderSet;
+import org.expath.httpclient.HttpClientError;
+import org.expath.httpclient.HttpClientException;
+import org.expath.httpclient.HttpConstants;
+import org.expath.httpclient.HttpRequestBody;
 import org.expath.tools.ToolsException;
 import org.expath.tools.model.Element;
 import org.expath.tools.model.Sequence;
 
+import javax.annotation.Nullable;
+
 /**
  * A multipart body in the request.
  *
@@ -59,7 +67,9 @@ public void setHeaders(HeaderSet headers)
             throws HttpClientException
     {
         // set the Content-Type header (if not set by the user)
-        if ( headers.getFirstHeader("Content-Type") == null ) {
+        @Nullable final Header explicitContentTypeHeader = headers.getFirstHeader("Content-Type");
+
+        if ( explicitContentTypeHeader == null ) {
             StringBuilder type = new StringBuilder(getContentType());
             type.append("; boundary=");
             type.append("\"");
@@ -71,6 +81,14 @@ public void setHeaders(HeaderSet headers)
             }
             type.append("\"");
             headers.add("Content-Type", type.toString());
+        } else {
+            // if the outer explicit http:header/@name="Content-Type" is not same as the http:multipart/@media-type then we have an invalid conflict
+            final ContentType explicitContentType = ContentType.parse(explicitContentTypeHeader, null, null);
+            final ContentType multipartMediaType =  ContentType.parse(new BasicHeader("Content-Type", getContentType()), null, null);
+
+            if (!explicitContentType.getType().equals(multipartMediaType.getType())) {
+                throw new HttpClientException(HttpClientError.HC007, "http:header/@name=\"Content-Type\" is " + explicitContentType.getType() + ", but http:multipart/@media-type is " + multipartMediaType.getType());
+            }
         }
     }
 

http-client-java/src/main/java/org/expath/httpclient/impl/RequestParser.java

@@ -148,7 +148,6 @@ else if ( "chunked".equals(local) ) {
         // walk the elements
         // TODO: Check element structure validity (header*, (multipart|body)?)
         HeaderSet headers = new HeaderSet();
-        req.setHeaders(headers);
         for ( Element child : myRequest.children() ) {
             String local = child.getLocalName();
             String ns = child.getNamespaceUri();
@@ -174,6 +173,7 @@ else if ( "body".equals(local) || "multipart".equals(local) ) {
                 throw new HttpClientException(HttpClientError.HC005, "Unknown element: " + local);
             }
         }
+        req.setHeaders(headers);
 
         return req;
     }