source: AE/installer2/src/net/oni2/aeinstaller/backend/network/DrupalJSONQuery.java@ 613

package net.oni2.aeinstaller.backend.network;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

import net.oni2.aeinstaller.backend.Settings;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.methods.HttpRequestBase;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

/**
 * @author Christian Illy
 */
public class DrupalJSONQuery {

        private static String getDepotUrl() {
                return Settings.getInstance().get("depot_api_url",
                                "http://mods.oni2.net/?q=api/");
        }

        /**
         * Execute an REST action through a HTTP POST query
         * 
         * @param resource
         *            Resource to run on
         * @param action
         *            Action to call
         * @param postData
         *            Fieldname / value pairs to include in POST data
         * @return JSON structure of item
         * @throws Exception
         *             on HTTP error
         */
        public static JSONArray postAction(String resource, String action,
                        HashMap<String, String> postData) throws Exception {
                try {
                        List<NameValuePair> nvps = new ArrayList<NameValuePair>();
                        for (String key : postData.keySet()) {
                                nvps.add(new BasicNameValuePair(key, postData.get(key)));
                        }
                        HttpEntity data = new UrlEncodedFormEntity(nvps);
                        return executeQuery(getDepotUrl() + resource + "/" + action
                                        + ".json", data);
                } catch (UnsupportedEncodingException e) {
                        e.printStackTrace();
                }
                return null;
        }

        /**
         * Execute an REST references query through a HTTP GET query
         * 
         * @param resource
         *            Resource to run on
         * @param index
         *            Index of item to get the references from
         * @param refName
         *            Name of references type
         * @return JSON structure of item
         * @throws Exception
         *             on HTTP error
         */
        public static JSONArray getReferences(String resource, int index,
                        String refName) throws Exception {
                return executeQuery(
                                getDepotUrl() + resource + "/" + Integer.toString(index) + "/"
                                                + refName + ".json", null);
        }

        /**
         * Execute an REST item query through a HTTP GET query
         * 
         * @param resource
         *            Resource to run on
         * @param index
         *            Index of item to get
         * @param parameters
         *            Parameters to pass (must start with ampersand "&")
         * @return JSON structure of item
         * @throws Exception
         *             on HTTP error
         */
        public static JSONArray getItem(String resource, int index,
                        String parameters) throws Exception {
                return executeQuery(
                                getDepotUrl() + resource + "/" + Integer.toString(index)
                                                + ".json" + parameters, null);
        }

        /**
         * Execute an REST index query through a HTTP GET query
         * 
         * @param resource
         *            Resource to run on
         * @param page
         *            Number of page to get (for limited results, e.g. nodes), -1 to
         *            ignore
         * @param pagesize
         *            Maximum number of elements to return
         * @return JSON structure of item
         * @throws Exception
         *             on HTTP error
         */
        public static JSONArray getIndex(String resource, int page, int pagesize)
                        throws Exception {
                String pageN = "";
                if (page >= 0)
                        pageN = "&page=" + Integer.toString(page);
                String pagesizeN = "";
                if (pagesize >= 0)
                        pagesizeN = "&pagesize=" + Integer.toString(pagesize);
                return executeQuery(getDepotUrl() + resource + ".json" + pageN
                                + pagesizeN, null);
        }

        private static JSONArray executeQuery(String url, HttpEntity postData)
                        throws Exception {
                BufferedReader input = null;
                HttpRequestBase httpQuery = null;

                try {
                        DefaultHttpClient httpclient = new DefaultHttpClient();
                        if (postData == null) {
                                httpQuery = new HttpGet(url);
                        } else {
                                httpQuery = new HttpPost(url);
                                ((HttpPost) httpQuery).setEntity(postData);
                        }

                        HttpResponse response = httpclient.execute(httpQuery);

                        int code = response.getStatusLine().getStatusCode();
                        if ((code > 299) || (code < 200)) {
                                throw new Exception(String.format(
                                                "Error fetching content (HTTP status code %d).", code));
                        }

                        HttpEntity entity = response.getEntity();

                        input = new BufferedReader(new InputStreamReader(
                                        entity.getContent()));
                        StringBuffer json = new StringBuffer();

                        char data[] = new char[1024];
                        int dataRead;
                        while ((dataRead = input.read(data, 0, 1024)) != -1) {
                                json.append(data, 0, dataRead);
                        }

                        EntityUtils.consume(entity);

                        JSONArray jA = null;
                        if (json.charAt(0) == '{') {
                                jA = new JSONArray();
                                jA.put(new JSONObject(json.toString()));
                        } else
                                jA = new JSONArray(json.toString());

                        return jA;
                } catch (JSONException e) {
                        e.printStackTrace();
                } catch (UnsupportedEncodingException e) {
                        e.printStackTrace();
                } catch (IOException e) {
                        e.printStackTrace();
                } finally {
                        if (httpQuery != null)
                                httpQuery.releaseConnection();
                        if (input != null) {
                                try {
                                        input.close();
                                } catch (IOException e) {
                                        e.printStackTrace();
                                }
                        }
                }
                return null;
        }
}