ConnectPCA.java

package org.occiware.clouddesigner.occi.infrastructure.connector;

import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClientBuilder;
import org.json.simple.JSONObject;
import org.json.simple.parser.JSONParser;
import org.json.simple.parser.ParseException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.Properties;


/**
 * Created by mael on 04/07/16.
 */
public class ConnectPCA {

    /**
     * Initialize the logger.
     */
    private static Logger LOGGER = LoggerFactory.getLogger(ComputeConnector.class);


    /**
     * Get the deployed instances from Cloud Automation Model
     *
     * @return a json object containing the request results
     */
    public JSONObject getRequest(String id)  {
        final String url = getProperty("server.endpoint")+id;
        JSONObject result = new JSONObject();
        try {
            CloseableHttpClient httpClient = HttpClientBuilder.create().build();
            HttpGet getRequest = new HttpGet(url);
            HttpResponse response = httpClient.execute(getRequest);
            String serverOutput = readHttpResponse(response);

            httpClient.close();
            result = (JSONObject) new JSONParser().parse(serverOutput);
        }catch (IOException e){
            raiseException(e);
        }catch (ParseException e){
            raiseException(e);
        }
        return result;
    }

    /**
     * Send a request to pca service with a header containing the session id and sending content
     * @param input which is send to the cloud automation service
     * @return the information about gathered from cloud automation service
     */
    public JSONObject postRequest(JSONObject input) {

        final String url = getProperty("server.endpoint");
        JSONObject result = new JSONObject();
        try {
            CloseableHttpClient httpClient = HttpClientBuilder.create().build();
            HttpPost postRequest = new HttpPost(url);
            StringEntity entity = new StringEntity(input.toJSONString());
            entity.setContentType("application/json");
            postRequest.setEntity(entity);
            HttpResponse response = httpClient.execute(postRequest);
            String serverOutput = readHttpResponse(response);
            httpClient.close();
            result = (JSONObject) new JSONParser().parse(serverOutput);
        } catch (IOException e){
            raiseException(e);
        } catch (ParseException e){
            raiseException(e);
        }
        return result;
    }

    private void raiseException(Exception e){
        LOGGER.debug("exception raised in : "+e.getClass()+", "+e.getMessage());
    }



    /**
     * Get the property from the configuration file config.properties
     * @param propertyKey is the key of the variable
     * @return the value of the variable
     */
    String getProperty(String propertyKey){
        Properties prop = new Properties();
        InputStream input = null;

        try {

            prop.load(getClass().getClassLoader().getResourceAsStream("config.properties"));

            // return the property value
            return prop.getProperty(propertyKey);

        } catch (IOException ex) {
            ex.printStackTrace();
            throw new RuntimeException("Unable to get the cloud automation service url from config.properties");
        } finally {
            if (input != null) {
                try {
                    input.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    /**
     * Read an http respond and convert it into a string
     * @param response is the http response
     * @return a string containing the information from response
     * @throws IOException occur if problem occur with the buffer
     */
    private String readHttpResponse(HttpResponse response) throws IOException {
        StringBuffer serverOutput = new StringBuffer();
        if (response.getStatusLine().getStatusCode() != 201 && response.getStatusLine().getStatusCode() != 200) {
            throw new RuntimeException("Send Request Failed : HTTP error code : "
                    + response.getStatusLine().getStatusCode());
        }

        BufferedReader br = new BufferedReader(
                new InputStreamReader((response.getEntity().getContent())));

        String output;
        while ((output = br.readLine()) != null) {
            serverOutput.append(output);
        }
        return serverOutput.toString();
    }

}