Reformat streaming results

Author: Max Hniebergall

server/src/main/java/org/elasticsearch/common/xcontent/ChunkedToXContentHelper.java

@@ -12,6 +12,7 @@
 import org.elasticsearch.common.collect.Iterators;
 import org.elasticsearch.xcontent.ToXContent;
 
+import java.util.Collections;
 import java.util.Iterator;
 
 public enum ChunkedToXContentHelper {
@@ -53,6 +54,14 @@ public static Iterator<ToXContent> field(String name, String value) {
         return Iterators.single(((builder, params) -> builder.field(name, value)));
     }
 
+    public static Iterator<ToXContent> optionalField(String name, String value) {
+        if (value == null) {
+            return Collections.emptyIterator();
+        } else {
+            return field(name, value);
+        }
+    }
+
     /**
      * Creates an Iterator of a single ToXContent object that serializes the given object as a single chunk. Just wraps {@link
      * Iterators#single}, but still useful because it avoids any type ambiguity.

server/src/main/java/org/elasticsearch/rest/ChunkedRestResponseBodyPart.java

@@ -173,11 +173,11 @@ public ReleasableBytesReference encodeChunk(int sizeHint, Recycler<BytesRef> rec
                     target = null;
                     return result;
                 } catch (Exception e) {
-                    logger.error("failure encoding chunk", e);
+                    logger.error("failure encoding chunk 5", e);
                     throw e;
                 } finally {
                     if (target != null) {
-                        assert false : "failure encoding chunk";
+                        assert false : "failure encoding chunk 6";
                         IOUtils.closeWhileHandlingException(target);
                         target = null;
                     }

server/src/main/java/org/elasticsearch/rest/ChunkedZipResponse.java

@@ -412,11 +412,11 @@ public ReleasableBytesReference encodeChunk(int sizeHint, Recycler<BytesRef> rec
                     return new ReleasableBytesReference(BytesArray.EMPTY, () -> {});
                 }
             } catch (Exception e) {
-                logger.error("failure encoding chunk", e);
+                logger.error("failure encoding chunk 7", e);
                 throw e;
             } finally {
                 if (targetStream != null) {
-                    assert false : "failure encoding chunk";
+                    assert false : "failure encoding chunk 8";
                     IOUtils.closeWhileHandlingException(targetStream, Releasables.wrap(releasables));
                     targetStream = null;
                 }

server/src/main/java/org/elasticsearch/rest/StreamingXContentResponse.java

@@ -364,11 +364,11 @@ public ReleasableBytesReference encodeChunk(int sizeHint, Recycler<BytesRef> rec
                     return new ReleasableBytesReference(BytesArray.EMPTY, () -> {});
                 }
             } catch (Exception e) {
-                logger.error("failure encoding chunk", e);
+                logger.error("failure encoding chunk 9", e);
                 throw e;
             } finally {
                 if (targetStream != null) {
-                    assert false : "failure encoding chunk";
+                    assert false : "failure encoding chunk 10";
                     IOUtils.closeWhileHandlingException(targetStream, Releasables.wrap(releasables));
                     targetStream = null;
                 }