private boolean validateQuery(final QueryBuilder query) {
  checkNotNull(query);
  try {
    ValidateQueryRequestBuilder validateRequest = indicesAdminClient().prepareValidateQuery().setQuery(query);
    if (log.isDebugEnabled()) {
      validateRequest.setExplain(true);
    }
    ValidateQueryResponse validateQueryResponse = validateRequest.execute().actionGet();
    if (!validateQueryResponse.isValid()) {
      if (log.isDebugEnabled()) {
        Collection<String> explanations = Collections2.transform(validateQueryResponse.getQueryExplanation(),
            new Function<QueryExplanation, String>()
            {
              @Nullable
              @Override
              public String apply(final QueryExplanation input) {
                return input.getExplanation() != null ? input.getExplanation() : input.getError();
              }
            });
        log.debug("Invalid query explanation: {}", explanations);
      }
      throw new IllegalArgumentException("Invalid query");
    }
    return true;
  }
  catch (IndexNotFoundException e) {
    // no repositories were created yet, so there is no point in searching
    return false;
  }
}
 

@Override
protected XContentBuilder toXContent(ValidateQueryRequest request, ValidateQueryResponse response, XContentBuilder builder) throws IOException {
    builder.startObject();
    builder.field("valid", response.isValid());
    buildBroadcastShardsHeader(builder, response);

    List<? extends QueryExplanation> queryExplanation = response.getQueryExplanation();

    if (queryExplanation != null && !queryExplanation.isEmpty()) {
        builder.startArray("explanations");
        for (QueryExplanation explanation : queryExplanation) {
            builder.startObject();
            if (explanation.getIndex() != null) {
                builder.field("index", explanation.getIndex(), XContentBuilder.FieldCaseConversion.NONE);
            }
            builder.field("valid", explanation.isValid());
            if (explanation.getError() != null) {
                builder.field("error", explanation.getError());
            }
            if (explanation.getExplanation() != null) {
                builder.field("explanation", explanation.getExplanation());
            }
            builder.endObject();
        }
        builder.endArray();
    }
    builder.endObject();
    return builder;
}
 

@Override
public void handleRequest(final RestRequest request, final RestChannel channel, final Client client) {
    ValidateQueryRequest validateQueryRequest = new ValidateQueryRequest(Strings.splitStringByCommaToArray(request.param("index")));
    validateQueryRequest.indicesOptions(IndicesOptions.fromRequest(request, validateQueryRequest.indicesOptions()));
    if (RestActions.hasBodyContent(request)) {
        validateQueryRequest.source(RestActions.getRestContent(request));
    } else {
        QuerySourceBuilder querySourceBuilder = RestActions.parseQuerySource(request);
        if (querySourceBuilder != null) {
            validateQueryRequest.source(querySourceBuilder);
        }
    }
    validateQueryRequest.types(Strings.splitStringByCommaToArray(request.param("type")));
    if (request.paramAsBoolean("explain", false)) {
        validateQueryRequest.explain(true);
    } else {
        validateQueryRequest.explain(false);
    }
    if (request.paramAsBoolean("rewrite", false)) {
        validateQueryRequest.rewrite(true);
    } else {
        validateQueryRequest.rewrite(false);
    }

    client.admin().indices().validateQuery(validateQueryRequest, new RestBuilderListener<ValidateQueryResponse>(channel) {
        @Override
        public RestResponse buildResponse(ValidateQueryResponse response, XContentBuilder builder) throws Exception {
            builder.startObject();
            builder.field("valid", response.isValid());

            buildBroadcastShardsHeader(builder, request, response);

            if (response.getQueryExplanation() != null && !response.getQueryExplanation().isEmpty()) {
                builder.startArray("explanations");
                for (QueryExplanation explanation : response.getQueryExplanation()) {
                    builder.startObject();
                    if (explanation.getIndex() != null) {
                        builder.field("index", explanation.getIndex(), XContentBuilder.FieldCaseConversion.NONE);
                    }
                    builder.field("valid", explanation.isValid());
                    if (explanation.getError() != null) {
                        builder.field("error", explanation.getError());
                    }
                    if (explanation.getExplanation() != null) {
                        builder.field("explanation", explanation.getExplanation());
                    }
                    builder.endObject();
                }
                builder.endArray();
            }
            builder.endObject();
            return new BytesRestResponse(OK, builder);
        }
    });
}