AsyncHttpClient.java

/*
    Android Asynchronous Http Client
    Copyright (c) 2011 James Smith <james@loopj.com>
    http://loopj.com

    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 com.madrobot.net;

import java.io.IOException;
import java.io.InputStream;
import java.lang.ref.WeakReference;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.WeakHashMap;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.zip.GZIPInputStream;

import org.apache.http.Header;
import org.apache.http.HeaderElement;
import org.apache.http.HttpEntity;
import org.apache.http.HttpRequest;
import org.apache.http.HttpRequestInterceptor;
import org.apache.http.HttpResponse;
import org.apache.http.HttpResponseInterceptor;
import org.apache.http.HttpVersion;
import org.apache.http.client.CookieStore;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpDelete;
import org.apache.http.client.methods.HttpEntityEnclosingRequestBase;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.methods.HttpPut;
import org.apache.http.client.methods.HttpUriRequest;
import org.apache.http.client.protocol.ClientContext;
import org.apache.http.conn.params.ConnManagerParams;
import org.apache.http.conn.params.ConnPerRouteBean;
import org.apache.http.conn.scheme.PlainSocketFactory;
import org.apache.http.conn.scheme.Scheme;
import org.apache.http.conn.scheme.SchemeRegistry;
import org.apache.http.conn.ssl.SSLSocketFactory;
import org.apache.http.entity.HttpEntityWrapper;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.impl.conn.tsccm.ThreadSafeClientConnManager;
import org.apache.http.params.BasicHttpParams;
import org.apache.http.params.HttpConnectionParams;
import org.apache.http.params.HttpProtocolParams;
import org.apache.http.protocol.BasicHttpContext;
import org.apache.http.protocol.HttpContext;
import org.apache.http.protocol.SyncBasicHttpContext;

import android.content.Context;


/**
 * The AsyncHttpClient can be used to make asynchronous GET, POST, PUT and 
 * DELETE HTTP requests in your Android applications. Requests can be made
 * with additional parameters by passing a {@link RequestParams} instance,
 * and responses can be handled by passing an anonymously overridden 
 * {@link AsyncHttpResponseHandler} instance.
 * <p>
 * For example:
 * <p>
 * <pre>
 * AsyncHttpClient client = new AsyncHttpClient();
 * client.get("http://www.google.com", new AsyncHttpResponseHandler() {
 *     &#064;Override
 *     public void onSuccess(String response) {
 *         System.out.println(response);
 *     }
 * });
 * </pre>
 * <b>Requests sent using AsyncHttpClient do NOT have to be in a separate thread. {@link AsyncHttpClient} maintains its own thread pool.</b>
 * @see RequestParams
 * @see AsyncHttpResponseHandler
 */
public class AsyncHttpClient {
    private static class InflatingEntity extends HttpEntityWrapper {
        public InflatingEntity(HttpEntity wrapped) {
            super(wrapped);
        }

        @Override
        public InputStream getContent() throws IOException {
            return new GZIPInputStream(wrappedEntity.getContent());
        }

        @Override
        public long getContentLength() {
            return -1;
        }
    }

    private static final int DEFAULT_MAX_CONNECTIONS = 10;
    private static final int DEFAULT_MAX_RETRIES = 5;
    private static final int DEFAULT_SOCKET_BUFFER_SIZE = 8192;
    private static final int DEFAULT_SOCKET_TIMEOUT = 10 * 1000;
    private static final String ENCODING_GZIP = "gzip";
    private static final String HEADER_ACCEPT_ENCODING = "Accept-Encoding";

    private static int maxConnections = DEFAULT_MAX_CONNECTIONS;
    private static int socketTimeout = DEFAULT_SOCKET_TIMEOUT;

    private static final String VERSION = "1.3.1";
    private final Map<String, String> clientHeaderMap;
	private final DefaultHttpClient httpClient;
    private final HttpContext httpContext;
    private final Map<Context, List<WeakReference<Future<?>>>> requestMap;


    private ThreadPoolExecutor threadPool;

    /**
     * Creates a new AsyncHttpClient.
     */
    public AsyncHttpClient() {
        BasicHttpParams httpParams = new BasicHttpParams();

        ConnManagerParams.setTimeout(httpParams, socketTimeout);
        ConnManagerParams.setMaxConnectionsPerRoute(httpParams, new ConnPerRouteBean(maxConnections));
        ConnManagerParams.setMaxTotalConnections(httpParams, DEFAULT_MAX_CONNECTIONS);

        HttpConnectionParams.setSoTimeout(httpParams, socketTimeout);
        HttpConnectionParams.setConnectionTimeout(httpParams, socketTimeout);
        HttpConnectionParams.setTcpNoDelay(httpParams, true);
        HttpConnectionParams.setSocketBufferSize(httpParams, DEFAULT_SOCKET_BUFFER_SIZE);

        HttpProtocolParams.setVersion(httpParams, HttpVersion.HTTP_1_1);
        HttpProtocolParams.setUserAgent(httpParams, String.format("android-async-http/%s (http://loopj.com/android-async-http)", VERSION));

        SchemeRegistry schemeRegistry = new SchemeRegistry();
        schemeRegistry.register(new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));
        schemeRegistry.register(new Scheme("https", SSLSocketFactory.getSocketFactory(), 443));
        ThreadSafeClientConnManager cm = new ThreadSafeClientConnManager(httpParams, schemeRegistry);

        httpContext = new SyncBasicHttpContext(new BasicHttpContext());
        httpClient = new DefaultHttpClient(cm, httpParams);
        httpClient.addRequestInterceptor(new HttpRequestInterceptor() {
            @Override
			public void process(HttpRequest request, HttpContext context) {
                if (!request.containsHeader(HEADER_ACCEPT_ENCODING)) {
                    request.addHeader(HEADER_ACCEPT_ENCODING, ENCODING_GZIP);
                }
                for (String header : clientHeaderMap.keySet()) {
                	request.addHeader(header, clientHeaderMap.get(header));
                }
            }
        });

        httpClient.addResponseInterceptor(new HttpResponseInterceptor() {
            @Override
			public void process(HttpResponse response, HttpContext context) {
                final HttpEntity entity = response.getEntity();
                final Header encoding = entity.getContentEncoding();
                if (encoding != null) {
                    for (HeaderElement element : encoding.getElements()) {
                        if (element.getName().equalsIgnoreCase(ENCODING_GZIP)) {
                            response.setEntity(new InflatingEntity(response.getEntity()));
                            break;
                        }
                    }
                }
            }
        });

        httpClient.setHttpRequestRetryHandler(new RetryHandler(DEFAULT_MAX_RETRIES));

        threadPool = (ThreadPoolExecutor)Executors.newCachedThreadPool();

        requestMap = new WeakHashMap<Context, List<WeakReference<Future<?>>>>();
        clientHeaderMap = new HashMap<String, String>();
    }

    private HttpEntityEnclosingRequestBase addEntityToRequestBase(HttpEntityEnclosingRequestBase requestBase, HttpEntity entity) {
        if(entity != null){
            requestBase.setEntity(entity);
        }

        return requestBase;
    }

    /**
     * Sets headers that will be added to all requests this client makes (before sending).
     * @param header the name of the header
     * @param value the contents of the header
     */
    public void addHeader(String header, String value) {
    	clientHeaderMap.put(header, value);
    }

    /**
     * Cancels any pending (or potentially active) requests associated with the
     * passed Context.
     * <p>
     * <b>Note:</b> This will only affect requests which were created with a non-null
     * android Context. This method is intended to be used in the onDestroy
     * method of your android activities to destroy all requests which are no
     * longer required.
     *
     * @param context the android Context instance associated to the request.
     * @param mayInterruptIfRunning specifies if active requests should be cancelled along with pending requests.
     */
    public void cancelRequests(Context context, boolean mayInterruptIfRunning) {
        List<WeakReference<Future<?>>> requestList = requestMap.get(context);
        if(requestList != null) {
            for(WeakReference<Future<?>> requestRef : requestList) {
                Future<?> request = requestRef.get();
                if(request != null) {
                    request.cancel(mayInterruptIfRunning);
                }
            }
        }
        requestMap.remove(context);
    }

    /**
     * Perform a HTTP DELETE request.
     * @param context the Android Context which initiated the request.
     * @param url the URL to send the request to.
     * @param responseHandler the response handler instance that should handle the response.
     */
    public void delete(Context context, String url, AsyncHttpResponseHandler responseHandler) {
        final HttpDelete delete = new HttpDelete(url);
        sendRequest(httpClient, httpContext, delete, null, responseHandler, context);
    }
    
    /**
     * Perform a HTTP DELETE request.
     * @param url the URL to send the request to.
     * @param responseHandler the response handler instance that should handle the response.
     */
    public void delete(String url, AsyncHttpResponseHandler responseHandler) {
        delete(null, url, responseHandler);
    }

    /**
     * Perform a HTTP GET request without any parameters and track the Android Context which initiated the request.
     * @param context the Android Context which initiated the request.
     * @param url the URL to send the request to.
     * @param responseHandler the response handler instance that should handle the response.
     */
    public void get(Context context, String url, AsyncHttpResponseHandler responseHandler) {
        get(context, url, null, responseHandler);
    }


    //
    // HTTP GET Requests
    //

    /**
     * Perform a HTTP GET request and track the Android Context which initiated the request.
     * @param context the Android Context which initiated the request.
     * @param url the URL to send the request to.
     * @param params additional GET parameters to send with the request.
     * @param responseHandler the response handler instance that should handle the response.
     */
    public void get(Context context, String url, RequestParams params, AsyncHttpResponseHandler responseHandler) {
        sendRequest(httpClient, httpContext, new HttpGet(getUrlWithQueryString(url, params)), null, responseHandler, context);
    }

    /**
     * Perform a HTTP GET request, without any parameters.
     * @param url the URL to send the request to.
     * @param responseHandler the response handler instance that should handle the response.
     */
    public void get(String url, AsyncHttpResponseHandler responseHandler) {
        get(null, url, null, responseHandler);
    }

    /**
     * Perform a HTTP GET request with parameters.
     * @param url the URL to send the request to.
     * @param params additional GET parameters to send with the request.
     * @param responseHandler the response handler instance that should handle the response.
     */
    public void get(String url, RequestParams params, AsyncHttpResponseHandler responseHandler) {
        get(null, url, params, responseHandler);
    }

    /**
     * Get the underlying HttpClient instance. This is useful for setting
     * additional fine-grained settings for requests by accessing the
     * client's ConnectionManager, HttpParams and SchemeRegistry.
     */
    public HttpClient getHttpClient() {
        return this.httpClient;
    }


    //
    // HTTP POST Requests
    //

    private String getUrlWithQueryString(String url, RequestParams params) {
        if(params != null) {
            String paramString = params.getParamString();
            url += "?" + paramString;
        }

        return url;
    }

    private HttpEntity paramsToEntity(RequestParams params) {
        HttpEntity entity = null;

        if(params != null) {
            entity = params.getEntity();
        }

        return entity;
    }

    /**
     * Perform a HTTP POST request and track the Android Context which initiated the request.
     * @param context the Android Context which initiated the request.
     * @param url the URL to send the request to.
     * @param entity a raw {@link HttpEntity} to send with the request, for example, use this to send string/json/xml payloads to a server by passing a {@link org.apache.http.entity.StringEntity}.
     * @param contentType the content type of the payload you are sending, for example application/json if sending a json payload.
     * @param responseHandler the response handler instance that should handle the response.
     */
    public void post(Context context, String url, HttpEntity entity, String contentType, AsyncHttpResponseHandler responseHandler) {
        sendRequest(httpClient, httpContext, addEntityToRequestBase(new HttpPost(url), entity), contentType, responseHandler, context);
    }

    /**
     * Perform a HTTP POST request and track the Android Context which initiated the request.
     * @param context the Android Context which initiated the request.
     * @param url the URL to send the request to.
     * @param params additional POST parameters or files to send with the request.
     * @param responseHandler the response handler instance that should handle the response.
     */
    public void post(Context context, String url, RequestParams params, AsyncHttpResponseHandler responseHandler) {
        post(context, url, paramsToEntity(params), null, responseHandler);
    }


    //
    // HTTP PUT Requests
    //

    /**
     * Perform a HTTP POST request, without any parameters.
     * @param url the URL to send the request to.
     * @param responseHandler the response handler instance that should handle the response.
     */
    public void post(String url, AsyncHttpResponseHandler responseHandler) {
        post(null, url, null, responseHandler);
    }

    /**
     * Perform a HTTP POST request with parameters.
     * @param url the URL to send the request to.
     * @param params additional POST parameters or files to send with the request.
     * @param responseHandler the response handler instance that should handle the response.
     */
    public void post(String url, RequestParams params, AsyncHttpResponseHandler responseHandler) {
        post(null, url, params, responseHandler);
    }

    /**
     * Perform a HTTP PUT request and track the Android Context which initiated the request.
     * @param context the Android Context which initiated the request.
     * @param url the URL to send the request to.
     * @param entity a raw {@link HttpEntity} to send with the request, for example, use this to send string/json/xml payloads to a server by passing a {@link org.apache.http.entity.StringEntity}.
     * @param contentType the content type of the payload you are sending, for example application/json if sending a json payload.
     * @param responseHandler the response handler instance that should handle the response.
     */
    public void put(Context context, String url, HttpEntity entity, String contentType, AsyncHttpResponseHandler responseHandler) {
        sendRequest(httpClient, httpContext, addEntityToRequestBase(new HttpPut(url), entity), contentType, responseHandler, context);
    }

    /**
     * Perform a HTTP PUT request and track the Android Context which initiated the request.
     * @param context the Android Context which initiated the request.
     * @param url the URL to send the request to.
     * @param params additional PUT parameters or files to send with the request.
     * @param responseHandler the response handler instance that should handle the response.
     */
    public void put(Context context, String url, RequestParams params, AsyncHttpResponseHandler responseHandler) {
        put(context, url, paramsToEntity(params), null, responseHandler);
    }


    //
    // HTTP DELETE Requests
    //

    /**
     * Perform a HTTP PUT request, without any parameters.
     * @param url the URL to send the request to.
     * @param responseHandler the response handler instance that should handle the response.
     */
    public void put(String url, AsyncHttpResponseHandler responseHandler) {
        put(null, url, null, responseHandler);
    }

    /**
     * Perform a HTTP PUT request with parameters.
     * @param url the URL to send the request to.
     * @param params additional PUT parameters or files to send with the request.
     * @param responseHandler the response handler instance that should handle the response.
     */
    public void put(String url, RequestParams params, AsyncHttpResponseHandler responseHandler) {
        put(null, url, params, responseHandler);
    }



    // Private stuff
    private void sendRequest(DefaultHttpClient client, HttpContext httpContext, HttpUriRequest uriRequest, String contentType, AsyncHttpResponseHandler responseHandler, Context context) {
        if(contentType != null) {
            uriRequest.addHeader("Content-Type", contentType);
        }

        Future<?> request = threadPool.submit(new AsyncHttpRequest(client, httpContext, uriRequest, responseHandler));

        if(context != null) {
            // Add request to request map
            List<WeakReference<Future<?>>> requestList = requestMap.get(context);
            if(requestList == null) {
                requestList = new LinkedList<WeakReference<Future<?>>>();
                requestMap.put(context, requestList);
            }

            requestList.add(new WeakReference<Future<?>>(request));

            // TODO: Remove dead weakrefs from requestLists?
        }
    }

    /**
     * Sets an optional CookieStore to use when making requests
     * @param cookieStore The CookieStore implementation to use, usually an instance of {@link PersistentCookieStore}
     */
    public void setCookieStore(CookieStore cookieStore) {
        httpContext.setAttribute(ClientContext.COOKIE_STORE, cookieStore);
    }

    /**
     * Sets the SSLSocketFactory to user when making requests. By default,
     * a new, default SSLSocketFactory is used.
     * @param sslSocketFactory the socket factory to use for https requests.
     */
    public void setSSLSocketFactory(SSLSocketFactory sslSocketFactory) {
        this.httpClient.getConnectionManager().getSchemeRegistry().register(new Scheme("https", sslSocketFactory, 443));
    }

    /**
     * Overrides the threadpool implementation used when queuing/pooling
     * requests. By default, Executors.newCachedThreadPool() is used.
     * @param threadPool an instance of {@link ThreadPoolExecutor} to use for queuing/pooling requests.
     */
    public void setThreadPool(ThreadPoolExecutor threadPool) {
        this.threadPool = threadPool;
    }

    /**
     * Sets the User-Agent header to be sent with each request. By default,
     * "Android Asynchronous Http Client/VERSION (http://loopj.com/android-async-http/)" is used.
     * @param userAgent the string to use in the User-Agent header.
     */
    public void setUserAgent(String userAgent) {
        HttpProtocolParams.setUserAgent(this.httpClient.getParams(), userAgent);
    }
}