io.wcm.caravan.pipeline.impl.JsonPathSelector.java Source code

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Here is the source code for io.wcm.caravan.pipeline.impl.JsonPathSelector.java

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/*
 * #%L
 * wcm.io
 * %%
 * Copyright (C) 2014 wcm.io
 * %%
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * #L%
 */
package io.wcm.caravan.pipeline.impl;

import static java.util.concurrent.TimeUnit.MILLISECONDS;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import rx.functions.Func1;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.node.ArrayNode;
import com.google.common.base.Stopwatch;
import com.jayway.jsonpath.Configuration;
import com.jayway.jsonpath.Configuration.ConfigurationBuilder;
import com.jayway.jsonpath.JsonPath;
import com.jayway.jsonpath.Option;
import com.jayway.jsonpath.PathNotFoundException;

/**
 * Function that evaluates a JSONpath expression on a Jackson {@link JsonNode} tree, and returns an {@link ArrayNode}
 * with all matching results.
 */
public final class JsonPathSelector implements Func1<JsonNode, ArrayNode> {

    private static final Logger log = LoggerFactory.getLogger(JsonPathSelector.class);

    private static Configuration config = new ConfigurationBuilder()
            .options(Option.REQUIRE_PROPERTIES, Option.ALWAYS_RETURN_LIST).build();

    private final String jsonPath;

    JsonPathSelector(String jsonPath) {
        this.jsonPath = jsonPath;
    }

    @Override
    public ArrayNode call(JsonNode inputData) throws PathNotFoundException {
        Stopwatch watch = Stopwatch.createStarted();

        ArrayNode arrayNode = JsonPath.using(config).parse(inputData).read(jsonPath, ArrayNode.class);

        log.debug("selected " + arrayNode.size() + " matches in " + watch.elapsed(MILLISECONDS)
                + " ms by applying jsonPath " + this.jsonPath);
        return arrayNode;
    }

}