Remove StatusToXContent interface (#99824)

The StatusToXContent interface extends ToXContent with a REST status
method. It is used by RestStatusToXContentListener, which uses the extra
method to set the status of the RestResponse. However, given the
generics parametrization of RestToXContentListener, we can already get
the status of a response object without having these extra interfaces,
which mix serialization and status concerns.

This commit removes StatusToXContent and RestStatusToXContentListener,
instead adding some extra optional parameters to RestToXContentListener to
handle retrieving status and location information from the passed in Response
object.

modules/lang-mustache/src/main/java/org/elasticsearch/script/mustache/RestSearchTemplateAction.java

@@ -15,7 +15,7 @@
 import org.elasticsearch.rest.RestRequest;
 import org.elasticsearch.rest.Scope;
 import org.elasticsearch.rest.ServerlessScope;
-import org.elasticsearch.rest.action.RestStatusToXContentListener;
+import org.elasticsearch.rest.action.RestToXContentListener;
 import org.elasticsearch.rest.action.search.RestSearchAction;
 import org.elasticsearch.xcontent.XContentParser;
 
@@ -76,7 +76,11 @@ public RestChannelConsumer prepareRequest(RestRequest request, NodeClient client
         if (searchRequest.source().explain() != null) {
             searchTemplateRequest.setExplain(searchRequest.source().explain());
         }
-        return channel -> client.execute(SearchTemplateAction.INSTANCE, searchTemplateRequest, new RestStatusToXContentListener<>(channel));
+        return channel -> client.execute(
+            SearchTemplateAction.INSTANCE,
+            searchTemplateRequest,
+            new RestToXContentListener<>(channel, SearchTemplateResponse::status)
+        );
     }
 
     @Override

modules/lang-mustache/src/main/java/org/elasticsearch/script/mustache/SearchTemplateResponse.java

@@ -14,9 +14,9 @@
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.xcontent.ChunkedToXContent;
-import org.elasticsearch.common.xcontent.StatusToXContentObject;
 import org.elasticsearch.rest.RestStatus;
 import org.elasticsearch.xcontent.ParseField;
+import org.elasticsearch.xcontent.ToXContentObject;
 import org.elasticsearch.xcontent.XContentBuilder;
 import org.elasticsearch.xcontent.XContentFactory;
 import org.elasticsearch.xcontent.XContentParser;
@@ -26,7 +26,7 @@
 import java.io.InputStream;
 import java.util.Map;
 
-public class SearchTemplateResponse extends ActionResponse implements StatusToXContentObject {
+public class SearchTemplateResponse extends ActionResponse implements ToXContentObject {
     public static ParseField TEMPLATE_OUTPUT_FIELD = new ParseField("template_output");
 
     /** Contains the source of the rendered template **/
@@ -113,7 +113,6 @@ void innerToXContent(XContentBuilder builder, Params params) throws IOException
         }
     }
 
-    @Override
     public RestStatus status() {
         if (hasResponse()) {
             return response.status();

qa/smoke-test-http/src/javaRestTest/java/org/elasticsearch/http/SystemIndexRestIT.java

@@ -9,6 +9,7 @@
 package org.elasticsearch.http;
 
 import org.elasticsearch.Version;
+import org.elasticsearch.action.DocWriteResponse;
 import org.elasticsearch.action.index.IndexRequest;
 import org.elasticsearch.action.support.WriteRequest;
 import org.elasticsearch.client.Request;
@@ -32,7 +33,7 @@
 import org.elasticsearch.rest.RestController;
 import org.elasticsearch.rest.RestHandler;
 import org.elasticsearch.rest.RestRequest;
-import org.elasticsearch.rest.action.RestStatusToXContentListener;
+import org.elasticsearch.rest.action.RestToXContentListener;
 import org.elasticsearch.xcontent.XContentBuilder;
 
 import java.io.IOException;
@@ -234,7 +235,7 @@ protected RestChannelConsumer prepareRequest(RestRequest request, NodeClient cli
                 indexRequest.source(Map.of("some_field", "some_value"));
                 return channel -> client.index(
                     indexRequest,
-                    new RestStatusToXContentListener<>(channel, r -> r.getLocation(indexRequest.routing()))
+                    new RestToXContentListener<>(channel, DocWriteResponse::status, r -> r.getLocation(indexRequest.routing()))
                 );
             }
         }

server/src/main/java/org/elasticsearch/action/DocWriteResponse.java

@@ -16,7 +16,6 @@
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.io.stream.Writeable;
-import org.elasticsearch.common.xcontent.StatusToXContentObject;
 import org.elasticsearch.core.Nullable;
 import org.elasticsearch.core.RestApiVersion;
 import org.elasticsearch.index.Index;
@@ -25,6 +24,7 @@
 import org.elasticsearch.index.seqno.SequenceNumbers;
 import org.elasticsearch.index.shard.ShardId;
 import org.elasticsearch.rest.RestStatus;
+import org.elasticsearch.xcontent.ToXContentObject;
 import org.elasticsearch.xcontent.XContentBuilder;
 import org.elasticsearch.xcontent.XContentParser;
 
@@ -41,7 +41,7 @@
 /**
  * A base class for the response of a write operation that involves a single doc
  */
-public abstract class DocWriteResponse extends ReplicationResponse implements WriteResponse, StatusToXContentObject {
+public abstract class DocWriteResponse extends ReplicationResponse implements WriteResponse, ToXContentObject {
 
     private static final String _SHARDS = "_shards";
     private static final String _INDEX = "_index";
@@ -216,7 +216,6 @@ public void setForcedRefresh(boolean forcedRefresh) {
     }
 
     /** returns the rest status for this response (based on {@link ShardInfo#status()} */
-    @Override
     public RestStatus status() {
         return getShardInfo().status();
     }

server/src/main/java/org/elasticsearch/action/admin/cluster/health/ClusterHealthResponse.java

@@ -18,12 +18,12 @@
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.util.Maps;
-import org.elasticsearch.common.xcontent.StatusToXContentObject;
 import org.elasticsearch.core.TimeValue;
 import org.elasticsearch.rest.RestStatus;
 import org.elasticsearch.xcontent.ConstructingObjectParser;
 import org.elasticsearch.xcontent.ObjectParser;
 import org.elasticsearch.xcontent.ParseField;
+import org.elasticsearch.xcontent.ToXContentObject;
 import org.elasticsearch.xcontent.XContentBuilder;
 import org.elasticsearch.xcontent.XContentParser;
 
@@ -37,7 +37,7 @@
 import static org.elasticsearch.xcontent.ConstructingObjectParser.constructorArg;
 import static org.elasticsearch.xcontent.ConstructingObjectParser.optionalConstructorArg;
 
-public class ClusterHealthResponse extends ActionResponse implements StatusToXContentObject {
+public class ClusterHealthResponse extends ActionResponse implements ToXContentObject {
     private static final String CLUSTER_NAME = "cluster_name";
     private static final String STATUS = "status";
     private static final String TIMED_OUT = "timed_out";
@@ -333,7 +333,6 @@ public String toString() {
         return Strings.toString(this);
     }
 
-    @Override
     public RestStatus status() {
         return isTimedOut() ? RestStatus.REQUEST_TIMEOUT : RestStatus.OK;
     }

server/src/main/java/org/elasticsearch/action/admin/cluster/storedscripts/GetScriptContextResponse.java

@@ -12,11 +12,10 @@
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.util.Maps;
-import org.elasticsearch.common.xcontent.StatusToXContentObject;
-import org.elasticsearch.rest.RestStatus;
 import org.elasticsearch.script.ScriptContextInfo;
 import org.elasticsearch.xcontent.ConstructingObjectParser;
 import org.elasticsearch.xcontent.ParseField;
+import org.elasticsearch.xcontent.ToXContentObject;
 import org.elasticsearch.xcontent.XContentBuilder;
 import org.elasticsearch.xcontent.XContentParser;
 
@@ -30,7 +29,7 @@
 import java.util.function.Function;
 import java.util.stream.Collectors;
 
-public class GetScriptContextResponse extends ActionResponse implements StatusToXContentObject {
+public class GetScriptContextResponse extends ActionResponse implements ToXContentObject {
 
     private static final ParseField CONTEXTS = new ParseField("contexts");
     final Map<String, ScriptContextInfo> contexts;
@@ -87,11 +86,6 @@ public void writeTo(StreamOutput out) throws IOException {
         }
     }
 
-    @Override
-    public RestStatus status() {
-        return RestStatus.OK;
-    }
-
     @Override
     public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
         builder.startObject().startArray(CONTEXTS.getPreferredName());

server/src/main/java/org/elasticsearch/action/admin/cluster/storedscripts/GetScriptLanguageResponse.java

@@ -12,16 +12,15 @@
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.io.stream.Writeable;
-import org.elasticsearch.common.xcontent.StatusToXContentObject;
-import org.elasticsearch.rest.RestStatus;
 import org.elasticsearch.script.ScriptLanguagesInfo;
+import org.elasticsearch.xcontent.ToXContentObject;
 import org.elasticsearch.xcontent.XContentBuilder;
 import org.elasticsearch.xcontent.XContentParser;
 
 import java.io.IOException;
 import java.util.Objects;
 
-public class GetScriptLanguageResponse extends ActionResponse implements StatusToXContentObject, Writeable {
+public class GetScriptLanguageResponse extends ActionResponse implements ToXContentObject, Writeable {
     public final ScriptLanguagesInfo info;
 
     GetScriptLanguageResponse(ScriptLanguagesInfo info) {
@@ -38,11 +37,6 @@ public void writeTo(StreamOutput out) throws IOException {
         info.writeTo(out);
     }
 
-    @Override
-    public RestStatus status() {
-        return RestStatus.OK;
-    }
-
     public static GetScriptLanguageResponse fromXContent(XContentParser parser) throws IOException {
         return new GetScriptLanguageResponse(ScriptLanguagesInfo.fromXContent(parser));
     }

server/src/main/java/org/elasticsearch/action/admin/cluster/storedscripts/GetStoredScriptResponse.java

@@ -11,12 +11,12 @@
 import org.elasticsearch.action.ActionResponse;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
-import org.elasticsearch.common.xcontent.StatusToXContentObject;
 import org.elasticsearch.rest.RestStatus;
 import org.elasticsearch.script.StoredScriptSource;
 import org.elasticsearch.xcontent.ConstructingObjectParser;
 import org.elasticsearch.xcontent.ObjectParser;
 import org.elasticsearch.xcontent.ParseField;
+import org.elasticsearch.xcontent.ToXContentObject;
 import org.elasticsearch.xcontent.XContentBuilder;
 import org.elasticsearch.xcontent.XContentParser;
 
@@ -26,7 +26,7 @@
 import static org.elasticsearch.xcontent.ConstructingObjectParser.constructorArg;
 import static org.elasticsearch.xcontent.ConstructingObjectParser.optionalConstructorArg;
 
-public class GetStoredScriptResponse extends ActionResponse implements StatusToXContentObject {
+public class GetStoredScriptResponse extends ActionResponse implements ToXContentObject {
 
     public static final ParseField _ID_PARSE_FIELD = new ParseField("_id");
     public static final ParseField FOUND_PARSE_FIELD = new ParseField("found");
@@ -84,7 +84,6 @@ public StoredScriptSource getSource() {
         return source;
     }
 
-    @Override
     public RestStatus status() {
         return source != null ? RestStatus.OK : RestStatus.NOT_FOUND;
     }

server/src/main/java/org/elasticsearch/action/admin/indices/dangling/list/ListDanglingIndicesResponse.java

@@ -14,8 +14,8 @@
 import org.elasticsearch.cluster.ClusterName;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
-import org.elasticsearch.common.xcontent.StatusToXContentObject;
 import org.elasticsearch.rest.RestStatus;
+import org.elasticsearch.xcontent.ToXContentObject;
 import org.elasticsearch.xcontent.XContent;
 import org.elasticsearch.xcontent.XContentBuilder;
 
@@ -34,7 +34,7 @@
  * information for each dangling index is presented under the "dangling_indices" key. If any nodes
  * in the cluster failed to answer, the details are presented under the "_nodes.failures" key.
  */
-public class ListDanglingIndicesResponse extends BaseNodesResponse<NodeListDanglingIndicesResponse> implements StatusToXContentObject {
+public class ListDanglingIndicesResponse extends BaseNodesResponse<NodeListDanglingIndicesResponse> implements ToXContentObject {
 
     public ListDanglingIndicesResponse(StreamInput in) throws IOException {
         super(in);
@@ -48,7 +48,6 @@ public ListDanglingIndicesResponse(
         super(clusterName, nodes, failures);
     }
 
-    @Override
     public RestStatus status() {
         return this.hasFailures() ? RestStatus.INTERNAL_SERVER_ERROR : RestStatus.OK;
     }

server/src/main/java/org/elasticsearch/action/bulk/BulkItemResponse.java

@@ -20,7 +20,6 @@
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.io.stream.Writeable;
-import org.elasticsearch.common.xcontent.StatusToXContentObject;
 import org.elasticsearch.core.CheckedConsumer;
 import org.elasticsearch.core.RestApiVersion;
 import org.elasticsearch.index.mapper.MapperService;
@@ -30,6 +29,7 @@
 import org.elasticsearch.xcontent.ConstructingObjectParser;
 import org.elasticsearch.xcontent.ParseField;
 import org.elasticsearch.xcontent.ToXContentFragment;
+import org.elasticsearch.xcontent.ToXContentObject;
 import org.elasticsearch.xcontent.XContentBuilder;
 import org.elasticsearch.xcontent.XContentParser;
 
@@ -44,14 +44,13 @@
  * Represents a single item response for an action executed as part of the bulk API. Holds the index/type/id
  * of the relevant action, and if it has failed or not (with the failure message in case it failed).
  */
-public class BulkItemResponse implements Writeable, StatusToXContentObject {
+public class BulkItemResponse implements Writeable, ToXContentObject {
 
     private static final String _INDEX = "_index";
     private static final String _ID = "_id";
     private static final String STATUS = "status";
     private static final String ERROR = "error";
 
-    @Override
     public RestStatus status() {
         return failure == null ? response.status() : failure.getStatus();
     }

server/src/main/java/org/elasticsearch/action/explain/ExplainResponse.java

@@ -13,13 +13,13 @@
 import org.elasticsearch.action.ActionResponse;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
-import org.elasticsearch.common.xcontent.StatusToXContentObject;
 import org.elasticsearch.core.RestApiVersion;
 import org.elasticsearch.index.get.GetResult;
 import org.elasticsearch.index.mapper.MapperService;
 import org.elasticsearch.rest.RestStatus;
 import org.elasticsearch.xcontent.ConstructingObjectParser;
 import org.elasticsearch.xcontent.ParseField;
+import org.elasticsearch.xcontent.ToXContentObject;
 import org.elasticsearch.xcontent.XContentBuilder;
 import org.elasticsearch.xcontent.XContentParser;
 
@@ -33,7 +33,7 @@
 /**
  * Response containing the score explanation.
  */
-public class ExplainResponse extends ActionResponse implements StatusToXContentObject {
+public class ExplainResponse extends ActionResponse implements ToXContentObject {
 
     private static final ParseField _INDEX = new ParseField("_index");
     private static final ParseField _ID = new ParseField("_id");
@@ -44,9 +44,9 @@ public class ExplainResponse extends ActionResponse implements StatusToXContentO
     private static final ParseField DETAILS = new ParseField("details");
     private static final ParseField GET = new ParseField("get");
 
-    private String index;
-    private String id;
-    private boolean exists;
+    private final String index;
+    private final String id;
+    private final boolean exists;
     private Explanation explanation;
     private GetResult getResult;
 
@@ -110,7 +110,6 @@ public GetResult getGetResult() {
         return getResult;
     }
 
-    @Override
     public RestStatus status() {
         return exists ? RestStatus.OK : RestStatus.NOT_FOUND;
     }

server/src/main/java/org/elasticsearch/action/ingest/GetPipelineResponse.java

@@ -13,9 +13,9 @@
 import org.elasticsearch.common.bytes.BytesReference;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
-import org.elasticsearch.common.xcontent.StatusToXContentObject;
 import org.elasticsearch.ingest.PipelineConfiguration;
 import org.elasticsearch.rest.RestStatus;
+import org.elasticsearch.xcontent.ToXContentObject;
 import org.elasticsearch.xcontent.XContentBuilder;
 import org.elasticsearch.xcontent.XContentParser;
 import org.elasticsearch.xcontent.XContentParser.Token;
@@ -29,9 +29,9 @@
 
 import static org.elasticsearch.common.xcontent.XContentParserUtils.ensureExpectedToken;
 
-public class GetPipelineResponse extends ActionResponse implements StatusToXContentObject {
+public class GetPipelineResponse extends ActionResponse implements ToXContentObject {
 
-    private List<PipelineConfiguration> pipelines;
+    private final List<PipelineConfiguration> pipelines;
     private final boolean summary;
 
     public GetPipelineResponse(StreamInput in) throws IOException {
@@ -76,7 +76,6 @@ public boolean isSummary() {
         return summary;
     }
 
-    @Override
     public RestStatus status() {
         return isFound() ? RestStatus.OK : RestStatus.NOT_FOUND;
     }