Setting "_content_type" in indexing request has no effect

Example below. I set the type as text/plain but it is identified as text/html.

```sh
#!/bin/sh

echo "\n\n Delete testidx \n"
curl -XDELETE "http://localhost:9200/testidx"

echo "\n\n Create index and mapping \n"
curl -XPUT "http://localhost:9200/testidx" -d'
{
  "mappings": {
    "session": {
      "properties": {
        "Content": {
          "properties": {
            "content": {
              "type": "attachment",
              "path": "full",
              "store": "yes",
              "fields": {
                "content": {
                  "type": "string",
                  "store": "yes"
                },
                "author": {
                  "type": "string",
                  "store": "yes"
                },
                "title": {
                  "type": "string",
                  "store": "yes"
                },
                "name": {
                  "type": "string",
                  "store": "yes"
                },
                "date": {
                  "type": "date",
                  "format": "dateOptionalTime",
                  "store": "yes"
                },
                "keywords": {
                  "type": "string",
                  "store": "yes"
                },
                "content_type": {
                  "type": "string",
                  "store": "yes"
                },
                "content_length": {
                  "type": "integer",
                  "store": "yes"
                }
              }
            }
          }
        }
      }
    }
  }
}'

echo "\n\n Index document \n"
curl -XPOST "http://localhost:9200/_bulk" -d'
  {"index":{"_index":"testidx","_type":"session"}}
  {"Content":[{"_content_type":"text/plain","content":"BASE64ENCODED_CONTENT"}]}
'

echo "\n\n Refresh \n"
curl -XPOST "http://localhost:9200/testidx/_refresh"

echo "\n\n Get doc type \n"
curl -XPOST "http://localhost:9200/testidx/_search?pretty" -d'
{
  "fields": ["Content.content.content_type","Content.content.content_length","Content.content"]
}'
```

Closes #65.
(cherry picked from commit 38075dc)

src/main/java/org/elasticsearch/index/mapper/attachment/AttachmentMapper.java

@@ -352,6 +352,7 @@ public class AttachmentMapper implements Mapper {
                     } else if ("_name".equals(currentFieldName)) {
                         name = parser.text();
                     } else if ("language".equals(currentFieldName)) {
+                        // TODO should be _language
                     	language = parser.text();
                     }
                 } else if (token == XContentParser.Token.VALUE_NUMBER) {
@@ -448,7 +449,11 @@ public class AttachmentMapper implements Mapper {
         }
 
         try {
+            if (contentType != null) {
+                context.externalValue(contentType);
+            } else {
                 context.externalValue(metadata.get(Metadata.CONTENT_TYPE));
+            }
             contentTypeMapper.parse(context);
         } catch(MapperParsingException e){
             if (!ignoreErrors) throw e;

src/test/java/org/elasticsearch/plugin/mapper/attachments/test/MultipleAttachmentIntegrationTests.java

@@ -38,6 +38,7 @@ import static org.hamcrest.Matchers.equalTo;
 /**
  * Test case for issue https://github.com/elasticsearch/elasticsearch-mapper-attachments/issues/18
  */
+@ElasticsearchIntegrationTest.ClusterScope(scope = ElasticsearchIntegrationTest.Scope.SUITE)
 public class MultipleAttachmentIntegrationTests extends ElasticsearchIntegrationTest {
     private boolean ignore_errors = true;
 
@@ -65,7 +66,6 @@ public class MultipleAttachmentIntegrationTests extends ElasticsearchIntegration
         ignore_errors = true;
         logger.info("creating index [test]");
         createIndex("test");
-        ensureGreen();
 
         String mapping = copyToStringFromClasspath("/org/elasticsearch/index/mapper/multipledocs/test-mapping.json");
         byte[] html = copyToBytesFromClasspath("/org/elasticsearch/index/mapper/xcontent/htmlWithValidDateMeta.html");
@@ -93,7 +93,6 @@ public class MultipleAttachmentIntegrationTests extends ElasticsearchIntegration
 
         logger.info("creating index [test]");
         createIndex("test");
-        ensureGreen();
 
         String mapping = copyToStringFromClasspath("/org/elasticsearch/index/mapper/multipledocs/test-mapping.json");
         byte[] html = copyToBytesFromClasspath("/org/elasticsearch/index/mapper/xcontent/htmlWithValidDateMeta.html");

src/test/java/org/elasticsearch/plugin/mapper/attachments/test/SimpleAttachmentIntegrationTests.java

@@ -21,6 +21,7 @@ package org.elasticsearch.plugin.mapper.attachments.test;
 
 import org.elasticsearch.action.count.CountResponse;
 import org.elasticsearch.common.settings.ImmutableSettings;
+import org.elasticsearch.action.search.SearchResponse;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.index.mapper.MapperParsingException;
 import org.elasticsearch.plugins.PluginsService;
@@ -35,10 +36,12 @@ import static org.elasticsearch.common.settings.ImmutableSettings.settingsBuilde
 import static org.elasticsearch.common.xcontent.XContentFactory.jsonBuilder;
 import static org.elasticsearch.index.query.QueryBuilders.queryString;
 import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.is;
 
 /**
  *
  */
+@ElasticsearchIntegrationTest.ClusterScope(scope = ElasticsearchIntegrationTest.Scope.SUITE)
 public class SimpleAttachmentIntegrationTests extends ElasticsearchIntegrationTest {
 
     @Override
@@ -53,7 +56,6 @@ public class SimpleAttachmentIntegrationTests extends ElasticsearchIntegrationTe
     public void createEmptyIndex() throws Exception {
         logger.info("creating index [test]");
         createIndex("test");
-        ensureGreen();
     }
 
     @Override
@@ -129,4 +131,30 @@ public class SimpleAttachmentIntegrationTests extends ElasticsearchIntegrationTe
 
         index("test", "person", jsonBuilder().startObject().field("file").startObject().endObject());
     }
+
+    @Test
+    public void testContentTypeAndName() throws Exception {
+        String dummyContentType = "text/my-dummy-content-type";
+        String dummyName = "my-dummy-name-txt";
+        String mapping = copyToStringFromClasspath("/org/elasticsearch/index/mapper/xcontent/test-mapping-store-content-type.json");
+        byte[] txt = copyToBytesFromClasspath("/org/elasticsearch/index/mapper/xcontent/testContentLength.txt");
+
+        client().admin().indices().putMapping(putMappingRequest("test").type("person").source(mapping)).actionGet();
+
+        index("test", "person", jsonBuilder().startObject().field("file").startObject().field("content", txt)
+                .field("_content_type", dummyContentType)
+                .field("_name", dummyName)
+                .endObject());
+        refresh();
+
+        SearchResponse response = client().prepareSearch("test")
+                .addField("content_type")
+                .addField("name")
+                .execute().get();
+        String contentType = response.getHits().getAt(0).getFields().get("file.content_type").getValue();
+        String name = response.getHits().getAt(0).getFields().get("file.name").getValue();
+        assertThat(contentType, is(dummyContentType));
+        assertThat(name, is(dummyName));
+    }
+
 }

src/test/resources/org/elasticsearch/index/mapper/xcontent/test-mapping-store-content-type.json

@@ -0,0 +1,13 @@
+{
+    "person":{
+        "properties":{
+            "file":{
+                "type":"attachment",
+                "fields": {
+                    "content_type" : {"store" : "yes"},
+                    "name" : {"store" : "yes"}
+                }
+            }
+        }
+    }
+}