1/*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.volley.toolbox;
18
19import com.android.volley.AuthFailureError;
20import com.android.volley.Request;
21import com.android.volley.Request.Method;
22
23import org.apache.http.Header;
24import org.apache.http.HttpEntity;
25import org.apache.http.HttpResponse;
26import org.apache.http.HttpStatus;
27import org.apache.http.ProtocolVersion;
28import org.apache.http.StatusLine;
29import org.apache.http.entity.BasicHttpEntity;
30import org.apache.http.message.BasicHeader;
31import org.apache.http.message.BasicHttpResponse;
32import org.apache.http.message.BasicStatusLine;
33
34import java.io.DataOutputStream;
35import java.io.IOException;
36import java.io.InputStream;
37import java.net.HttpURLConnection;
38import java.net.URL;
39import java.util.HashMap;
40import java.util.List;
41import java.util.Map;
42import java.util.Map.Entry;
43
44import javax.net.ssl.HttpsURLConnection;
45import javax.net.ssl.SSLSocketFactory;
46
47/**
48 * An {@link HttpStack} based on {@link HttpURLConnection}.
49 */
50public class HurlStack implements HttpStack {
51
52    private static final String HEADER_CONTENT_TYPE = "Content-Type";
53
54    /**
55     * An interface for transforming URLs before use.
56     */
57    public interface UrlRewriter {
58        /**
59         * Returns a URL to use instead of the provided one, or null to indicate
60         * this URL should not be used at all.
61         */
62        public String rewriteUrl(String originalUrl);
63    }
64
65    private final UrlRewriter mUrlRewriter;
66    private final SSLSocketFactory mSslSocketFactory;
67
68    public HurlStack() {
69        this(null);
70    }
71
72    /**
73     * @param urlRewriter Rewriter to use for request URLs
74     */
75    public HurlStack(UrlRewriter urlRewriter) {
76        this(urlRewriter, null);
77    }
78
79    /**
80     * @param urlRewriter Rewriter to use for request URLs
81     * @param sslSocketFactory SSL factory to use for HTTPS connections
82     */
83    public HurlStack(UrlRewriter urlRewriter, SSLSocketFactory sslSocketFactory) {
84        mUrlRewriter = urlRewriter;
85        mSslSocketFactory = sslSocketFactory;
86    }
87
88    @Override
89    public HttpResponse performRequest(Request<?> request, Map<String, String> additionalHeaders)
90            throws IOException, AuthFailureError {
91        String url = request.getUrl();
92        HashMap<String, String> map = new HashMap<String, String>();
93        map.putAll(request.getHeaders());
94        map.putAll(additionalHeaders);
95        if (mUrlRewriter != null) {
96            String rewritten = mUrlRewriter.rewriteUrl(url);
97            if (rewritten == null) {
98                throw new IOException("URL blocked by rewriter: " + url);
99            }
100            url = rewritten;
101        }
102        URL parsedUrl = new URL(url);
103        HttpURLConnection connection = openConnection(parsedUrl, request);
104        for (String headerName : map.keySet()) {
105            connection.addRequestProperty(headerName, map.get(headerName));
106        }
107        setConnectionParametersForRequest(connection, request);
108        // Initialize HttpResponse with data from the HttpURLConnection.
109        ProtocolVersion protocolVersion = new ProtocolVersion("HTTP", 1, 1);
110        int responseCode = connection.getResponseCode();
111        if (responseCode == -1) {
112            // -1 is returned by getResponseCode() if the response code could not be retrieved.
113            // Signal to the caller that something was wrong with the connection.
114            throw new IOException("Could not retrieve response code from HttpUrlConnection.");
115        }
116        StatusLine responseStatus = new BasicStatusLine(protocolVersion,
117                connection.getResponseCode(), connection.getResponseMessage());
118        BasicHttpResponse response = new BasicHttpResponse(responseStatus);
119        if (hasResponseBody(request.getMethod(), responseStatus.getStatusCode())) {
120            response.setEntity(entityFromConnection(connection));
121        }
122        for (Entry<String, List<String>> header : connection.getHeaderFields().entrySet()) {
123            if (header.getKey() != null) {
124                Header h = new BasicHeader(header.getKey(), header.getValue().get(0));
125                response.addHeader(h);
126            }
127        }
128        return response;
129    }
130
131    /**
132     * Checks if a response message contains a body.
133     * @see <a href="https://tools.ietf.org/html/rfc7230#section-3.3">RFC 7230 section 3.3</a>
134     * @param requestMethod request method
135     * @param responseCode response status code
136     * @return whether the response has a body
137     */
138    private static boolean hasResponseBody(int requestMethod, int responseCode) {
139        return requestMethod != Request.Method.HEAD
140            && !(HttpStatus.SC_CONTINUE <= responseCode && responseCode < HttpStatus.SC_OK)
141            && responseCode != HttpStatus.SC_NO_CONTENT
142            && responseCode != HttpStatus.SC_NOT_MODIFIED;
143    }
144
145    /**
146     * Initializes an {@link HttpEntity} from the given {@link HttpURLConnection}.
147     * @param connection
148     * @return an HttpEntity populated with data from <code>connection</code>.
149     */
150    private static HttpEntity entityFromConnection(HttpURLConnection connection) {
151        BasicHttpEntity entity = new BasicHttpEntity();
152        InputStream inputStream;
153        try {
154            inputStream = connection.getInputStream();
155        } catch (IOException ioe) {
156            inputStream = connection.getErrorStream();
157        }
158        entity.setContent(inputStream);
159        entity.setContentLength(connection.getContentLength());
160        entity.setContentEncoding(connection.getContentEncoding());
161        entity.setContentType(connection.getContentType());
162        return entity;
163    }
164
165    /**
166     * Create an {@link HttpURLConnection} for the specified {@code url}.
167     */
168    protected HttpURLConnection createConnection(URL url) throws IOException {
169        HttpURLConnection connection = (HttpURLConnection) url.openConnection();
170
171        // Workaround for the M release HttpURLConnection not observing the
172        // HttpURLConnection.setFollowRedirects() property.
173        // https://code.google.com/p/android/issues/detail?id=194495
174        connection.setInstanceFollowRedirects(HttpURLConnection.getFollowRedirects());
175
176        return connection;
177    }
178
179    /**
180     * Opens an {@link HttpURLConnection} with parameters.
181     * @param url
182     * @return an open connection
183     * @throws IOException
184     */
185    private HttpURLConnection openConnection(URL url, Request<?> request) throws IOException {
186        HttpURLConnection connection = createConnection(url);
187
188        int timeoutMs = request.getTimeoutMs();
189        connection.setConnectTimeout(timeoutMs);
190        connection.setReadTimeout(timeoutMs);
191        connection.setUseCaches(false);
192        connection.setDoInput(true);
193
194        // use caller-provided custom SslSocketFactory, if any, for HTTPS
195        if ("https".equals(url.getProtocol()) && mSslSocketFactory != null) {
196            ((HttpsURLConnection)connection).setSSLSocketFactory(mSslSocketFactory);
197        }
198
199        return connection;
200    }
201
202    @SuppressWarnings("deprecation")
203    /* package */ static void setConnectionParametersForRequest(HttpURLConnection connection,
204            Request<?> request) throws IOException, AuthFailureError {
205        switch (request.getMethod()) {
206            case Method.DEPRECATED_GET_OR_POST:
207                // This is the deprecated way that needs to be handled for backwards compatibility.
208                // If the request's post body is null, then the assumption is that the request is
209                // GET.  Otherwise, it is assumed that the request is a POST.
210                byte[] postBody = request.getPostBody();
211                if (postBody != null) {
212                    // Prepare output. There is no need to set Content-Length explicitly,
213                    // since this is handled by HttpURLConnection using the size of the prepared
214                    // output stream.
215                    connection.setDoOutput(true);
216                    connection.setRequestMethod("POST");
217                    connection.addRequestProperty(HEADER_CONTENT_TYPE,
218                            request.getPostBodyContentType());
219                    DataOutputStream out = new DataOutputStream(connection.getOutputStream());
220                    out.write(postBody);
221                    out.close();
222                }
223                break;
224            case Method.GET:
225                // Not necessary to set the request method because connection defaults to GET but
226                // being explicit here.
227                connection.setRequestMethod("GET");
228                break;
229            case Method.DELETE:
230                connection.setRequestMethod("DELETE");
231                break;
232            case Method.POST:
233                connection.setRequestMethod("POST");
234                addBodyIfExists(connection, request);
235                break;
236            case Method.PUT:
237                connection.setRequestMethod("PUT");
238                addBodyIfExists(connection, request);
239                break;
240            case Method.HEAD:
241                connection.setRequestMethod("HEAD");
242                break;
243            case Method.OPTIONS:
244                connection.setRequestMethod("OPTIONS");
245                break;
246            case Method.TRACE:
247                connection.setRequestMethod("TRACE");
248                break;
249            case Method.PATCH:
250                connection.setRequestMethod("PATCH");
251                addBodyIfExists(connection, request);
252                break;
253            default:
254                throw new IllegalStateException("Unknown method type.");
255        }
256    }
257
258    private static void addBodyIfExists(HttpURLConnection connection, Request<?> request)
259            throws IOException, AuthFailureError {
260        byte[] body = request.getBody();
261        if (body != null) {
262            connection.setDoOutput(true);
263            connection.addRequestProperty(HEADER_CONTENT_TYPE, request.getBodyContentType());
264            DataOutputStream out = new DataOutputStream(connection.getOutputStream());
265            out.write(body);
266            out.close();
267        }
268    }
269}
270