edu.lternet.pasta.client.ProvenanceFactoryClient.java Source code

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Here is the source code for edu.lternet.pasta.client.ProvenanceFactoryClient.java

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/*
 *
 * $Date:$
 * $Author:$
 * $Revision:$
 *
 * Copyright 2011,2012 the University of New Mexico.
 *
 * This work was supported by National Science Foundation Cooperative
 * Agreements #DEB-0832652 and #DEB-0936498.
 *
 * 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.
 *
 */

package edu.lternet.pasta.client;

import java.io.IOException;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPut;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClientBuilder;
import org.apache.http.util.EntityUtils;
import org.apache.log4j.Logger;

import edu.lternet.pasta.portal.ConfigurationListener;

/**
 * @author servilla
 * @since August 7, 2012
 * 
 *        The ProvenanceFactoryClient provides an interface to the PASTA
 *        Provenance Factory service.
 * 
 */
public class ProvenanceFactoryClient extends PastaClient {

    /*
     * Class variables
     */

    private static final Logger logger = Logger.getLogger(edu.lternet.pasta.client.ProvenanceFactoryClient.class);

    /*
     * Instance variables
     */

    private final String BASE_URL;

    /*
     * Constructors
     */

    /**
     * @param uid
     * @throws PastaAuthenticationException
     * @throws PastaConfigurationException
     */
    public ProvenanceFactoryClient(String uid) throws PastaAuthenticationException, PastaConfigurationException {
        super(uid);
        String pastaUrl = PastaClient.composePastaUrl(this.pastaProtocol, this.pastaHost, this.pastaPort);
        this.BASE_URL = pastaUrl + "/package/provenance/eml";
    }

    /**
     * Returns the EML provenance metadata fragment as an XML string enclosed
     * by a <methodStep> element for the provided package identifier.
     * 
     * @param packageId The packageId of the parent data package whose provenance
     *                  metadata is being generated and returned.
     * @return an XML string containing the generated provenance metadata inside
     *         a <methodStep> element
     * @throws PastaEventException 
     */
    public String getProvenanceByPid(String packageId) throws Exception {
        String provenanceXml = null;
        Integer statusCode = null;
        HttpEntity responseEntity = null;
        CloseableHttpClient httpClient = HttpClientBuilder.create().build();
        HttpResponse response = null;
        String urlFragment = packageId.replace('.', '/');
        String provenanceURL = String.format("%s/%s", BASE_URL, urlFragment);
        HttpGet httpGet = new HttpGet(provenanceURL);

        // Set header content
        if (this.token != null) {
            httpGet.setHeader("Cookie", "auth-token=" + this.token);
        }

        try {
            response = httpClient.execute(httpGet);
            statusCode = (Integer) response.getStatusLine().getStatusCode();
            responseEntity = response.getEntity();

            if (responseEntity != null) {
                provenanceXml = EntityUtils.toString(responseEntity);
            }
        } catch (ClientProtocolException e) {
            logger.error(e);
            e.printStackTrace();
        } catch (IOException e) {
            logger.error(e);
            e.printStackTrace();
        } finally {
            closeHttpClient(httpClient);
        }

        if (statusCode != HttpStatus.SC_OK) {
            // Something went wrong; return message from the response entity
            String gripe = String.format("The Metadata Factory responded with response code %d and message '%s'.\n",
                    statusCode, provenanceXml);
            throw new PastaEventException(gripe);
        }

        return provenanceXml;
    }

    /**
     * @param args
     */
    public static void main(String[] args) {
        ConfigurationListener.configure();

        try {
            ProvenanceFactoryClient pfc = new ProvenanceFactoryClient("ucarroll");
            String provenanceXml = pfc.getProvenanceByPid("lter-landsat.7.1");
            logger.info("Provenance XML: \n" + provenanceXml);

        } catch (PastaAuthenticationException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (PastaConfigurationException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (PastaEventException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

}