fi.helsinki.cs.iot.hub.api.handlers.applications.ApplicationGetRequestHandler.java Source code

Introduction

Here is the source code for fi.helsinki.cs.iot.hub.api.handlers.applications.ApplicationGetRequestHandler.java

Source

/*
 * fi.helsinki.cs.iot.hub.api.ApplicationGetRequestHandler
 * v0.1
 * 2015
 *
 * Copyright 2015 University of Helsinki
 * 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 fi.helsinki.cs.iot.hub.api.handlers.applications;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.nio.file.Path;
import java.util.ArrayList;
import java.util.List;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.HttpClientBuilder;

import fi.helsinki.cs.iot.hub.api.handlers.basic.IotHubApiRequestHandler;
import fi.helsinki.cs.iot.hub.api.request.IotHubRequest;
import fi.helsinki.cs.iot.hub.jsengine.DuktapeJavascriptEngineWrapper;
import fi.helsinki.cs.iot.hub.utils.Log;
import fi.helsinki.cs.iot.hub.webserver.NanoHTTPD.Method;
import fi.helsinki.cs.iot.hub.webserver.NanoHTTPD.Response;

/**
 * 
 * @author Julien Mineraud <julien.mineraud@cs.helsinki.fi>
 *
 */
public class ApplicationGetRequestHandler extends IotHubApiRequestHandler {

    private static final String TAG = "ApplicationGetRequestHandler";
    private Path libdir;
    private List<Method> methods;

    public ApplicationGetRequestHandler(Path libdir) {
        this.libdir = libdir;
        this.methods = new ArrayList<>();
        this.methods.add(Method.GET);
    }

    @Override
    public Response handleRequest(IotHubRequest uri) {
        Log.d(TAG, "Got a request");
        // Case where we just want to list the libraires
        if (uri.getIdentifiers().size() == 0) {
            //Quick try for executing javascript code
            HttpClient httpclient = HttpClientBuilder.create().build();
            // Prepare a request object
            HttpGet httpget = new HttpGet("http://localhost:8080/libraries/test_jsoo.js");
            // Execute the request
            HttpResponse response;
            try {
                response = httpclient.execute(httpget);
                // Get hold of the response entity
                HttpEntity entity = response.getEntity();
                // If the response does not enclose an entity, there is no need
                // to worry about connection release
                if (entity != null) {
                    // A Simple JSON Response Read
                    InputStream instream = entity.getContent();
                    String result = convertStreamToString(instream);
                    DuktapeJavascriptEngineWrapper wrapper = new DuktapeJavascriptEngineWrapper(libdir);
                    wrapper.runScript(result);
                    instream.close();
                }
            } catch (Exception e) {
                getResponseKo("TODO", e.getMessage());
            }
            return getResponseOk("");
        } else if (uri.getIdentifiers().size() == 1) {
            //Quick try for executing javascript code
            HttpClient httpclient = HttpClientBuilder.create().build();
            // Prepare a request object
            HttpGet httpget = new HttpGet("http://localhost:8080/libraries/" + uri.getIdentifiers().get(0));
            // Execute the request
            HttpResponse response;
            try {
                response = httpclient.execute(httpget);
                // Get hold of the response entity
                HttpEntity entity = response.getEntity();
                // If the response does not enclose an entity, there is no need
                // to worry about connection release
                if (entity != null) {
                    // A Simple JSON Response Read
                    InputStream instream = entity.getContent();
                    String result = convertStreamToString(instream);
                    DuktapeJavascriptEngineWrapper wrapper = new DuktapeJavascriptEngineWrapper(libdir);
                    wrapper.runScript(result);
                    instream.close();
                }
            } catch (Exception e) {
                getResponseKo("TODO", e.getMessage());
            }
            return getResponseOk("Run is finished");
        } else {
            return getResponseKo(STATUS_NOT_YET_IMPLEMENTED, STATUS_NOT_YET_IMPLEMENTED);
        }
    }

    @Override
    public List<Method> getSupportedMethods() {
        return methods;
    }

    //http://www.vogella.com/code/com.vogella.android.webservice.rest/src/com/vogella/android/webservice/rest/RestClient.html
    private static String convertStreamToString(InputStream is) {
        /*
         * To convert the InputStream to String we use the BufferedReader.readLine()
         * method. We iterate until the BufferedReader return null which means
         * there's no more data to read. Each line will appended to a StringBuilder
         * and returned as String.
         */
        BufferedReader reader = new BufferedReader(new InputStreamReader(is));
        StringBuilder sb = new StringBuilder();

        String line = null;
        try {
            while ((line = reader.readLine()) != null) {
                sb.append(line + "\n");
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                is.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return sb.toString();
    }

}