| // Copyright 2017 The Cobalt Authors. All Rights Reserved. |
| // |
| // 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 dev.cobalt.coat; |
| |
| import static dev.cobalt.util.Log.TAG; |
| |
| import dev.cobalt.util.Log; |
| import java.io.BufferedInputStream; |
| import java.io.ByteArrayOutputStream; |
| import java.io.IOException; |
| import java.net.HttpURLConnection; |
| import java.net.URL; |
| |
| /** Helper class that implements an HTTP POST function used by DRM one-time provisioning. */ |
| public class CobaltHttpHelper { |
| private static final int RETRY_SLEEP_MILLIS = 250; |
| private static final int MAX_ATTEMPTS = 3; |
| |
| /** Exception representing a transient HTTP failure (eg, 500). */ |
| private static class TransientFailure extends Exception {} |
| |
| private static void sleepBeforeRetry() { |
| try { |
| Thread.sleep(RETRY_SLEEP_MILLIS); |
| } catch (InterruptedException ex) { |
| // should never happen |
| } |
| } |
| |
| /** |
| * Performs an HTTP POST, sending postData to url and returning the response contents on 200. |
| * |
| * <p>Note that this function retries temporary failures (network, HTTP 500) a few times. |
| * |
| * <p>Note also that this sets a few DRM-specific headers. |
| * |
| * @return response contents on success, null for permanent failure or exception. |
| */ |
| public byte[] performDrmHttpPost(String url) { |
| for (int attempts = 0; attempts < MAX_ATTEMPTS; attempts++) { |
| try { |
| return internalPerformHttpPost(url); |
| } catch (IOException ex) { |
| Log.w(TAG, "performHttpPost IOException: ", ex); |
| // continue below |
| } catch (TransientFailure ex) { |
| // continue below |
| } catch (Throwable tr) { |
| // All other exceptions are caught because the caller is expected |
| // to be a JNI function, where exception handling is inconvenient. |
| Log.e(TAG, "performHttpPost exception: ", tr); |
| return null; |
| } |
| sleepBeforeRetry(); |
| } |
| Log.w(TAG, "performHttpPost: Max attempts attempted"); |
| return null; |
| } |
| |
| private byte[] internalPerformHttpPost(String url) throws IOException, TransientFailure { |
| HttpURLConnection conn = (HttpURLConnection) new URL(url).openConnection(); |
| try { |
| conn.setRequestMethod("POST"); |
| conn.setDoOutput(false); |
| conn.setDoInput(true); |
| |
| int statusCode = conn.getResponseCode(); |
| |
| if (statusCode >= 500 && statusCode <= 599) { |
| // We retry on 5xx failures. |
| Log.i(TAG, "performHttpPost transient failure: " + conn.getResponseMessage()); |
| throw new TransientFailure(); |
| } |
| |
| if (statusCode != 200) { |
| Log.i(TAG, "performHttpPost permanent failure: " + conn.getResponseMessage()); |
| return null; |
| } |
| |
| ByteArrayOutputStream output = new ByteArrayOutputStream(); |
| BufferedInputStream input = new BufferedInputStream(conn.getInputStream()); |
| for (int b = input.read(); b != -1; b = input.read()) { |
| output.write(b); |
| } |
| |
| return output.toByteArray(); |
| } finally { |
| conn.disconnect(); |
| } |
| } |
| } |