/** * Copyright (c) 2016, SIREn Solutions. All Rights Reserved. * * This file is part of the SIREn project. * * SIREn is a free software: you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License as * published by the Free Software Foundation, either version 3 of * the License, or (at your option) any later version. * * SIREn is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Affero General Public License for more details. * * You should have received a copy of the GNU Affero General Public * License along with this program. If not, see <http://www.gnu.org/licenses/>. */ package solutions.siren.join.action.coordinate; import com.google.common.collect.Iterators; import org.elasticsearch.action.search.MultiSearchResponse; import org.elasticsearch.action.search.SearchResponse; import org.elasticsearch.common.Nullable; import org.elasticsearch.common.io.stream.StreamInput; import org.elasticsearch.common.io.stream.StreamOutput; import org.elasticsearch.common.xcontent.XContentBuilder; import org.elasticsearch.common.xcontent.XContentBuilderString; import java.io.IOException; import java.util.Iterator; /** * A multi search response from a coordinated action. * <br> * Hack: This is mainly a copy-paste of {@link org.elasticsearch.action.search.MultiSearchResponse} with a change in * {@link CoordinateMultiSearchResponse.Item#readFrom(StreamInput)} * to instantiate a {@link CoordinateSearchResponse} instead of a {@link SearchResponse}. We were not able to * extend it since {@link org.elasticsearch.action.search.MultiSearchResponse.Item} contains private constructors * and variables. * * todo: push a patch to Elasticsearch to make the variables protected instead of private, and review implementation. */ public class CoordinateMultiSearchResponse extends MultiSearchResponse { /** * A search response item, holding the actual search response, or an error message if it failed. * <br> * Extends {@link org.elasticsearch.action.search.MultiSearchResponse.Item} just to keep {@link MultiSearchResponse} * API compatibility. Since {@link org.elasticsearch.action.search.MultiSearchResponse.Item} has private variables, * we can't reuse them and need to re-implement everything with our own set of variables. * * @see org.elasticsearch.action.search.MultiSearchResponse.Item */ public static class Item extends MultiSearchResponse.Item { private SearchResponse response; private String failureMessage; Item() { super(null, null); // hack: empty constructor is private, use this one instead } public Item(SearchResponse response, String failureMessage) { super(null, null); // hack: empty constructor since we can't use parent's private variables. this.response = response; this.failureMessage = failureMessage; } /** * Is it a failed search? */ public boolean isFailure() { return failureMessage != null; } /** * The actual failure message, null if its not a failure. */ @Nullable public String getFailureMessage() { return failureMessage; } /** * The actual search response, null if its a failure. */ @Nullable public SearchResponse getResponse() { return this.response; } public static Item readItem(StreamInput in) throws IOException { Item item = new Item(); item.readFrom(in); return item; } @Override public void readFrom(StreamInput in) throws IOException { if (in.readBoolean()) { this.response = new CoordinateSearchResponse(); response.readFrom(in); } else { failureMessage = in.readString(); } } @Override public void writeTo(StreamOutput out) throws IOException { if (response != null) { out.writeBoolean(true); response.writeTo(out); } else { out.writeBoolean(false); out.writeString(failureMessage); } } } private Item[] items; CoordinateMultiSearchResponse() { // hack: empty constructor is private, use this one instead // we use an empty array to avoid NPE during serialization super(new MultiSearchResponse.Item[0]); } public CoordinateMultiSearchResponse(Item[] items) { super(new MultiSearchResponse.Item[0]); // hack: empty constructor is private this.items = items; } @Override public Iterator<MultiSearchResponse.Item> iterator() { return Iterators.forArray((MultiSearchResponse.Item[]) items); } /** * The list of responses, the order is the same as the one provided in the request. */ public Item[] getResponses() { return this.items; } @Override public void readFrom(StreamInput in) throws IOException { super.readFrom(in); items = new Item[in.readVInt()]; for (int i = 0; i < items.length; i++) { items[i] = Item.readItem(in); } } @Override public void writeTo(StreamOutput out) throws IOException { super.writeTo(out); out.writeVInt(items.length); for (Item item : items) { item.writeTo(out); } } @Override public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException { builder.startArray(Fields.RESPONSES); for (Item item : items) { if (item.isFailure()) { builder.startObject(); builder.field(Fields.ERROR, item.getFailureMessage()); builder.endObject(); } else { builder.startObject(); item.getResponse().toXContent(builder, params); builder.endObject(); } } builder.endArray(); return builder; } static final class Fields { static final XContentBuilderString RESPONSES = new XContentBuilderString("responses"); static final XContentBuilderString ERROR = new XContentBuilderString("error"); } }