org.apache.streams.data.moreover.MoreoverClient.java Source code

Introduction

Here is the source code for org.apache.streams.data.moreover.MoreoverClient.java

Source

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 *
 *   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.
 */

package org.apache.streams.data.moreover;

import com.google.common.annotations.VisibleForTesting;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.StringWriter;
import java.math.BigInteger;
import java.net.HttpURLConnection;
import java.net.URL;
import java.nio.charset.Charset;
import java.util.Date;

/**
 *
 */
public class MoreoverClient {
    private static final Logger logger = LoggerFactory.getLogger(MoreoverClient.class);

    protected static final String BASE_URL = "http://metabase.moreover.com/api/v10/articles?key=%s&limit=%s";
    protected static final String SEQUENCE_ID_PARAM = "&sequence_id=%s";

    public static final int MAX_LIMIT = 500; //according to moreover api documentation

    private final String id;
    private String apiKey;
    private String lastSequenceId;
    //testing purpose only
    public long pullTime;
    private boolean debug;

    public MoreoverClient(String id, String apiKey, String sequence) {
        logger.info("Constructed new client for id:{} key:{} sequence:{}", id, apiKey, sequence);
        this.id = id;
        this.apiKey = apiKey;
        this.lastSequenceId = sequence;
    }

    /**
     * Creates the url string that will be used to pull data.  If sequenceId is null, the sequence id param
     * is not added to the url string.
     * @param key moreover api key
     * @param limit
     * @param sequenceId
     * @return
     */
    @VisibleForTesting
    protected String getUrlString(String key, int limit, String sequenceId) {
        String url = String.format(BASE_URL, key, limit);
        if (sequenceId != null) {
            url += String.format(SEQUENCE_ID_PARAM, sequenceId);
        }
        return url;
    }

    public long getPullTime() {
        return this.pullTime;
    }

    public MoreoverResult getArticlesAfter(String sequenceId, int limit) throws IOException {
        String urlString = getUrlString(this.apiKey, limit, sequenceId);
        logger.debug("Making call to {}", urlString);
        long start = System.nanoTime();
        MoreoverResult result = new MoreoverResult(id, getArticles(new URL(urlString)), start, System.nanoTime());
        result.process();
        if (!result.getMaxSequencedId().equals(BigInteger.ZERO) && (this.lastSequenceId == null
                || !this.lastSequenceId.equals(result.getMaxSequencedId().toString()))) {
            this.lastSequenceId = result.getMaxSequencedId().toString();
            logger.debug("Maximum sequence from last call {}", this.lastSequenceId);
        } else {
            logger.debug("No maximum sequence returned in last call. Previous sequence = {}", this.lastSequenceId);
        }
        return result;
    }

    public MoreoverResult getNextBatch() throws IOException {
        logger.debug("Getting next results for {} {} {}", this.id, this.apiKey, this.lastSequenceId);
        return getArticlesAfter(this.lastSequenceId, MAX_LIMIT);
    }

    private String getArticles2(URL url) throws IOException {
        HttpURLConnection cn = (HttpURLConnection) url.openConnection();
        cn.setRequestMethod("GET");
        cn.addRequestProperty("Content-Type", "text/xml;charset=UTF-8");
        cn.setDoInput(true);
        cn.setDoOutput(false);
        BufferedReader reader = new BufferedReader(
                new InputStreamReader(cn.getInputStream(), Charset.forName("UTF-8")));
        String line = null;
        StringBuilder builder = new StringBuilder();
        String s = "";
        String result = new String(s.getBytes(Charset.forName("UTF-8")), Charset.forName("UTF-8"));
        while ((line = reader.readLine()) != null) {
            result += line;
        }
        pullTime = new Date().getTime();
        return result;
    }

    private String getArticles(URL url) throws IOException {
        HttpURLConnection cn = (HttpURLConnection) url.openConnection();
        cn.setRequestMethod("GET");
        cn.addRequestProperty("Content-Type", "text/xml;charset=UTF-8");
        cn.setDoInput(true);
        cn.setDoOutput(false);
        StringWriter writer = new StringWriter();
        IOUtils.copy(new InputStreamReader(cn.getInputStream(), Charset.forName("UTF-8")), writer);
        writer.flush();
        pullTime = new Date().getTime();

        // added after seeing java.net.SocketException: Too many open files
        cn.disconnect();

        return writer.toString();
    }
}