android/src/main/java/com/google/samples/apps/iosched/gcm/ServerUtilities.java - platform/external/iosched - Git at Google

 /*
  * Copyright 2014 Google Inc. 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 com.google.samples.apps.iosched.gcm;

 import android.content.Context;
 import android.content.SharedPreferences;
 import android.content.SharedPreferences.Editor;
 import android.text.TextUtils;

 import com.google.samples.apps.iosched.Config;
 import com.google.samples.apps.iosched.util.AccountUtils;

 import java.io.IOException;
 import java.io.OutputStream;
 import java.net.HttpURLConnection;
 import java.net.MalformedURLException;
 import java.net.URL;
 import java.util.*;
 import java.util.Map.Entry;

 import static com.google.samples.apps.iosched.util.LogUtils.*;

 /**
  * Helper class used to communicate with the demo server.
  */
 public final class ServerUtilities {
     private static final String TAG = makeLogTag("GCMs");

     private static final String PREFERENCES = "com.google.samples.apps.iosched.gcm";
     private static final String PROPERTY_REGISTERED_TS = "registered_ts";
     private static final String PROPERTY_REG_ID = "reg_id";
     private static final String PROPERTY_GCM_KEY = "gcm_key";
     private static final int MAX_ATTEMPTS = 5;
     private static final int BACKOFF_MILLI_SECONDS = 2000;

     private static final Random sRandom = new Random();

     private static boolean checkGcmEnabled() {
         if (TextUtils.isEmpty(Config.GCM_SERVER_URL)) {
             LOGD(TAG, "GCM feature disabled (no URL configured)");
             return false;
         } else if (TextUtils.isEmpty(Config.GCM_API_KEY)) {
             LOGD(TAG, "GCM feature disabled (no API key configured)");
             return false;
         } else if (TextUtils.isEmpty(Config.GCM_SENDER_ID)) {
             LOGD(TAG, "GCM feature disabled (no sender ID configured)");
             return false;
         }
         return true;
     }

     /**
      * Register this account/device pair within the server.
      *
      * @param context Current context
      * @param gcmId   The GCM registration ID for this device
      * @param gcmKey  The GCM key with which to register.
      * @return whether the registration succeeded or not.
      */
     public static boolean register(final Context context, final String gcmId, final String gcmKey) {
         if (!checkGcmEnabled()) {
             return false;
         }

         LOGI(TAG, "registering device (gcm_id = " + gcmId + ")");
         String serverUrl = Config.GCM_SERVER_URL + "/register";
         LOGI(TAG, "registering on GCM with GCM key: " + AccountUtils.sanitizeGcmKey(gcmKey));

         Map<String, String> params = new HashMap<String, String>();
         params.put("gcm_id", gcmId);
         params.put("gcm_key", gcmKey);
         long backoff = BACKOFF_MILLI_SECONDS + sRandom.nextInt(1000);
         // Once GCM returns a registration id, we need to register it in the
         // demo server. As the server might be down, we will retry it a couple
         // times.
         for (int i = 1; i <= MAX_ATTEMPTS; i++) {
             LOGV(TAG, "Attempt #" + i + " to register");
             try {
                 post(serverUrl, params, Config.GCM_API_KEY);
                 setRegisteredOnServer(context, true, gcmId, gcmKey);
                 return true;
             } catch (IOException e) {
                 // Here we are simplifying and retrying on any error; in a real
                 // application, it should retry only on unrecoverable errors
                 // (like HTTP error code 503).
                 LOGE(TAG, "Failed to register on attempt " + i, e);
                 if (i == MAX_ATTEMPTS) {
                     break;
                 }
                 try {
                     LOGV(TAG, "Sleeping for " + backoff + " ms before retry");
                     Thread.sleep(backoff);
                 } catch (InterruptedException e1) {
                     // Activity finished before we complete - exit.
                     LOGD(TAG, "Thread interrupted: abort remaining retries!");
                     Thread.currentThread().interrupt();
                     return false;
                 }
                 // increase backoff exponentially
                 backoff *= 2;
             }
         }
         return false;
     }

     /**
      * Unregister this account/device pair within the server.
      *
      * @param context Current context
      * @param gcmId   The GCM registration ID for this device
      */
     static void unregister(final Context context, final String gcmId) {
         if (!checkGcmEnabled()) {
             return;
         }

         LOGI(TAG, "unregistering device (gcmId = " + gcmId + ")");
         String serverUrl = Config.GCM_SERVER_URL + "/unregister";
         Map<String, String> params = new HashMap<String, String>();
         params.put("gcm_id", gcmId);
         try {
             post(serverUrl, params, Config.GCM_API_KEY);
             setRegisteredOnServer(context, false, gcmId, null);
         } catch (IOException e) {
             // At this point the device is unregistered from GCM, but still
             // registered in the server.
             // We could try to unregister again, but it is not necessary:
             // if the server tries to send a message to the device, it will get
             // a "NotRegistered" error message and should unregister the device.
             LOGD(TAG, "Unable to unregister from application server", e);
         } finally {
             // Regardless of server success, clear local preferences
             setRegisteredOnServer(context, false, null, null);
         }
     }

     /**
      * Request user data sync.
      *
      * @param context Current context
      */
     public static void notifyUserDataChanged(final Context context) {
         if (!checkGcmEnabled()) {
             return;
         }

         LOGI(TAG, "Notifying GCM that user data changed");
         String serverUrl = Config.GCM_SERVER_URL + "/send/self/sync_user";
         try {
             String gcmKey = AccountUtils.getGcmKey(context, AccountUtils.getActiveAccountName(context));
             if (gcmKey != null) {
                 post(serverUrl, new HashMap<String, String>(), gcmKey);
             }
         } catch (IOException e) {
             LOGE(TAG, "Unable to notify GCM about user data change", e);
         }
     }

     /**
      * Sets whether the device was successfully registered in the server side.
      *
      * @param context Current context
      * @param flag    True if registration was successful, false otherwise
      * @param gcmId    True if registration was successful, false otherwise
      */
     private static void setRegisteredOnServer(Context context, boolean flag, String gcmId, String gcmKey) {
         final SharedPreferences prefs = context.getSharedPreferences(
                 PREFERENCES, Context.MODE_PRIVATE);
         LOGD(TAG, "Setting registered on server status as: " + flag + ", gcmKey="
                 + AccountUtils.sanitizeGcmKey(gcmKey));
         Editor editor = prefs.edit();
         if (flag) {
             editor.putLong(PROPERTY_REGISTERED_TS, new Date().getTime());
             editor.putString(PROPERTY_GCM_KEY, gcmKey == null ? "" : gcmKey);
             editor.putString(PROPERTY_REG_ID, gcmId);
         } else {
             editor.remove(PROPERTY_REG_ID);
         }
         editor.commit();
     }

     /**
      * Checks whether the device was successfully registered in the server side.
      *
      * @param context Current context
      * @return True if registration was successful, false otherwise
      */
     public static boolean isRegisteredOnServer(Context context, String gcmKey) {
         final SharedPreferences prefs = context.getSharedPreferences(
                 PREFERENCES, Context.MODE_PRIVATE);
         // Find registration threshold
         Calendar cal = Calendar.getInstance();
         cal.add(Calendar.DATE, -1);
         long yesterdayTS = cal.getTimeInMillis();
         long regTS = prefs.getLong(PROPERTY_REGISTERED_TS, 0);

         gcmKey = gcmKey == null ? "" : gcmKey;

         if (regTS > yesterdayTS) {
             LOGV(TAG, "GCM registration current. regTS=" + regTS + " yesterdayTS=" + yesterdayTS);

             final String registeredGcmKey = prefs.getString(PROPERTY_GCM_KEY, "");
             if (registeredGcmKey.equals(gcmKey)) {
                 LOGD(TAG, "GCM registration is valid and for the correct gcm key: "
                         + AccountUtils.sanitizeGcmKey(registeredGcmKey));
                 return true;
             }
             LOGD(TAG, "GCM registration is for DIFFERENT gcm key "
                     + AccountUtils.sanitizeGcmKey(registeredGcmKey) + ". We were expecting "
                     + AccountUtils.sanitizeGcmKey(gcmKey));
             return false;
         } else {
             LOGV(TAG, "GCM registration expired. regTS=" + regTS + " yesterdayTS=" + yesterdayTS);
             return false;
         }
     }

     public static String getGcmId(Context context) {
         final SharedPreferences prefs = context.getSharedPreferences(PREFERENCES, Context.MODE_PRIVATE);
         return prefs.getString(PROPERTY_REG_ID, null);
     }

     /**
      *  Unregister the current GCM ID when we sign-out
      *
      * @param context Current context
      */
     public static void onSignOut(Context context) {
         String gcmId = getGcmId(context);
         if (gcmId != null) {
             unregister(context, gcmId);
         }
     }

     /**
      * Issue a POST request to the server.
      *
      * @param endpoint POST address.
      * @param params   request parameters.
      * @throws java.io.IOException propagated from POST.
      */
     private static void post(String endpoint, Map<String, String> params, String key)
             throws IOException {
         URL url;
         try {
             url = new URL(endpoint);
         } catch (MalformedURLException e) {
             throw new IllegalArgumentException("invalid url: " + endpoint);
         }
         params.put("key", key);
         StringBuilder bodyBuilder = new StringBuilder();
         Iterator<Entry<String, String>> iterator = params.entrySet().iterator();
         // constructs the POST body using the parameters
         while (iterator.hasNext()) {
             Entry<String, String> param = iterator.next();
             bodyBuilder.append(param.getKey()).append('=')
                     .append(param.getValue());
             if (iterator.hasNext()) {
                 bodyBuilder.append('&');
             }
         }
         String body = bodyBuilder.toString();
         LOGV(TAG, "Posting '" + body + "' to " + url);
         HttpURLConnection conn = null;
         try {
             conn = (HttpURLConnection) url.openConnection();
             conn.setDoOutput(true);
             conn.setUseCaches(false);
             conn.setChunkedStreamingMode(0);
             conn.setRequestMethod("POST");
             conn.setRequestProperty("Content-Type",
                     "application/x-www-form-urlencoded;charset=UTF-8");
             conn.setRequestProperty("Content-Length",
                     Integer.toString(body.length()));
             // post the request
             OutputStream out = conn.getOutputStream();
             out.write(body.getBytes());
             out.close();
             // handle the response
             int status = conn.getResponseCode();
             if (status != 200) {
                 throw new IOException("Post failed with error code " + status);
             }
         } finally {
             if (conn != null) {
                 conn.disconnect();
             }
         }
     }
 }
	/*
	* Copyright 2014 Google Inc. 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 com.google.samples.apps.iosched.gcm;

	import android.content.Context;
	import android.content.SharedPreferences;
	import android.content.SharedPreferences.Editor;
	import android.text.TextUtils;

	import com.google.samples.apps.iosched.Config;
	import com.google.samples.apps.iosched.util.AccountUtils;

	import java.io.IOException;
	import java.io.OutputStream;
	import java.net.HttpURLConnection;
	import java.net.MalformedURLException;
	import java.net.URL;
	import java.util.*;
	import java.util.Map.Entry;

	import static com.google.samples.apps.iosched.util.LogUtils.*;

	/**
	* Helper class used to communicate with the demo server.
	*/
	public final class ServerUtilities {
	private static final String TAG = makeLogTag("GCMs");

	private static final String PREFERENCES = "com.google.samples.apps.iosched.gcm";
	private static final String PROPERTY_REGISTERED_TS = "registered_ts";
	private static final String PROPERTY_REG_ID = "reg_id";
	private static final String PROPERTY_GCM_KEY = "gcm_key";
	private static final int MAX_ATTEMPTS = 5;
	private static final int BACKOFF_MILLI_SECONDS = 2000;

	private static final Random sRandom = new Random();

	private static boolean checkGcmEnabled() {
	if (TextUtils.isEmpty(Config.GCM_SERVER_URL)) {
	LOGD(TAG, "GCM feature disabled (no URL configured)");
	return false;
	} else if (TextUtils.isEmpty(Config.GCM_API_KEY)) {
	LOGD(TAG, "GCM feature disabled (no API key configured)");
	return false;
	} else if (TextUtils.isEmpty(Config.GCM_SENDER_ID)) {
	LOGD(TAG, "GCM feature disabled (no sender ID configured)");
	return false;
	}
	return true;
	}

	/**
	* Register this account/device pair within the server.
	*
	* @param context Current context
	* @param gcmId The GCM registration ID for this device
	* @param gcmKey The GCM key with which to register.
	* @return whether the registration succeeded or not.
	*/
	public static boolean register(final Context context, final String gcmId, final String gcmKey) {
	if (!checkGcmEnabled()) {
	return false;
	}

	LOGI(TAG, "registering device (gcm_id = " + gcmId + ")");
	String serverUrl = Config.GCM_SERVER_URL + "/register";
	LOGI(TAG, "registering on GCM with GCM key: " + AccountUtils.sanitizeGcmKey(gcmKey));

	Map<String, String> params = new HashMap<String, String>();
	params.put("gcm_id", gcmId);
	params.put("gcm_key", gcmKey);
	long backoff = BACKOFF_MILLI_SECONDS + sRandom.nextInt(1000);
	// Once GCM returns a registration id, we need to register it in the
	// demo server. As the server might be down, we will retry it a couple
	// times.
	for (int i = 1; i <= MAX_ATTEMPTS; i++) {
	LOGV(TAG, "Attempt #" + i + " to register");
	try {
	post(serverUrl, params, Config.GCM_API_KEY);
	setRegisteredOnServer(context, true, gcmId, gcmKey);
	return true;
	} catch (IOException e) {
	// Here we are simplifying and retrying on any error; in a real
	// application, it should retry only on unrecoverable errors
	// (like HTTP error code 503).
	LOGE(TAG, "Failed to register on attempt " + i, e);
	if (i == MAX_ATTEMPTS) {
	break;
	}
	try {
	LOGV(TAG, "Sleeping for " + backoff + " ms before retry");
	Thread.sleep(backoff);
	} catch (InterruptedException e1) {
	// Activity finished before we complete - exit.
	LOGD(TAG, "Thread interrupted: abort remaining retries!");
	Thread.currentThread().interrupt();
	return false;
	}
	// increase backoff exponentially
	backoff *= 2;
	}
	}
	return false;
	}

	/**
	* Unregister this account/device pair within the server.
	*
	* @param context Current context
	* @param gcmId The GCM registration ID for this device
	*/
	static void unregister(final Context context, final String gcmId) {
	if (!checkGcmEnabled()) {
	return;
	}

	LOGI(TAG, "unregistering device (gcmId = " + gcmId + ")");
	String serverUrl = Config.GCM_SERVER_URL + "/unregister";
	Map<String, String> params = new HashMap<String, String>();
	params.put("gcm_id", gcmId);
	try {
	post(serverUrl, params, Config.GCM_API_KEY);
	setRegisteredOnServer(context, false, gcmId, null);
	} catch (IOException e) {
	// At this point the device is unregistered from GCM, but still
	// registered in the server.
	// We could try to unregister again, but it is not necessary:
	// if the server tries to send a message to the device, it will get
	// a "NotRegistered" error message and should unregister the device.
	LOGD(TAG, "Unable to unregister from application server", e);
	} finally {
	// Regardless of server success, clear local preferences
	setRegisteredOnServer(context, false, null, null);
	}
	}

	/**
	* Request user data sync.
	*
	* @param context Current context
	*/
	public static void notifyUserDataChanged(final Context context) {
	if (!checkGcmEnabled()) {
	return;
	}

	LOGI(TAG, "Notifying GCM that user data changed");
	String serverUrl = Config.GCM_SERVER_URL + "/send/self/sync_user";
	try {
	String gcmKey = AccountUtils.getGcmKey(context, AccountUtils.getActiveAccountName(context));
	if (gcmKey != null) {
	post(serverUrl, new HashMap<String, String>(), gcmKey);
	}
	} catch (IOException e) {
	LOGE(TAG, "Unable to notify GCM about user data change", e);
	}
	}

	/**
	* Sets whether the device was successfully registered in the server side.
	*
	* @param context Current context
	* @param flag True if registration was successful, false otherwise
	* @param gcmId True if registration was successful, false otherwise
	*/
	private static void setRegisteredOnServer(Context context, boolean flag, String gcmId, String gcmKey) {
	final SharedPreferences prefs = context.getSharedPreferences(
	PREFERENCES, Context.MODE_PRIVATE);
	LOGD(TAG, "Setting registered on server status as: " + flag + ", gcmKey="
	+ AccountUtils.sanitizeGcmKey(gcmKey));
	Editor editor = prefs.edit();
	if (flag) {
	editor.putLong(PROPERTY_REGISTERED_TS, new Date().getTime());
	editor.putString(PROPERTY_GCM_KEY, gcmKey == null ? "" : gcmKey);
	editor.putString(PROPERTY_REG_ID, gcmId);
	} else {
	editor.remove(PROPERTY_REG_ID);
	}
	editor.commit();
	}

	/**
	* Checks whether the device was successfully registered in the server side.
	*
	* @param context Current context
	* @return True if registration was successful, false otherwise
	*/
	public static boolean isRegisteredOnServer(Context context, String gcmKey) {
	final SharedPreferences prefs = context.getSharedPreferences(
	PREFERENCES, Context.MODE_PRIVATE);
	// Find registration threshold
	Calendar cal = Calendar.getInstance();
	cal.add(Calendar.DATE, -1);
	long yesterdayTS = cal.getTimeInMillis();
	long regTS = prefs.getLong(PROPERTY_REGISTERED_TS, 0);

	gcmKey = gcmKey == null ? "" : gcmKey;

	if (regTS > yesterdayTS) {
	LOGV(TAG, "GCM registration current. regTS=" + regTS + " yesterdayTS=" + yesterdayTS);

	final String registeredGcmKey = prefs.getString(PROPERTY_GCM_KEY, "");
	if (registeredGcmKey.equals(gcmKey)) {
	LOGD(TAG, "GCM registration is valid and for the correct gcm key: "
	+ AccountUtils.sanitizeGcmKey(registeredGcmKey));
	return true;
	}
	LOGD(TAG, "GCM registration is for DIFFERENT gcm key "
	+ AccountUtils.sanitizeGcmKey(registeredGcmKey) + ". We were expecting "
	+ AccountUtils.sanitizeGcmKey(gcmKey));
	return false;
	} else {
	LOGV(TAG, "GCM registration expired. regTS=" + regTS + " yesterdayTS=" + yesterdayTS);
	return false;
	}
	}

	public static String getGcmId(Context context) {
	final SharedPreferences prefs = context.getSharedPreferences(PREFERENCES, Context.MODE_PRIVATE);
	return prefs.getString(PROPERTY_REG_ID, null);
	}

	/**
	* Unregister the current GCM ID when we sign-out
	*
	* @param context Current context
	*/
	public static void onSignOut(Context context) {
	String gcmId = getGcmId(context);
	if (gcmId != null) {
	unregister(context, gcmId);
	}
	}

	/**
	* Issue a POST request to the server.
	*
	* @param endpoint POST address.
	* @param params request parameters.
	* @throws java.io.IOException propagated from POST.
	*/
	private static void post(String endpoint, Map<String, String> params, String key)
	throws IOException {
	URL url;
	try {
	url = new URL(endpoint);
	} catch (MalformedURLException e) {
	throw new IllegalArgumentException("invalid url: " + endpoint);
	}
	params.put("key", key);
	StringBuilder bodyBuilder = new StringBuilder();
	Iterator<Entry<String, String>> iterator = params.entrySet().iterator();
	// constructs the POST body using the parameters
	while (iterator.hasNext()) {
	Entry<String, String> param = iterator.next();
	bodyBuilder.append(param.getKey()).append('=')
	.append(param.getValue());
	if (iterator.hasNext()) {
	bodyBuilder.append('&');
	}
	}
	String body = bodyBuilder.toString();
	LOGV(TAG, "Posting '" + body + "' to " + url);
	HttpURLConnection conn = null;
	try {
	conn = (HttpURLConnection) url.openConnection();
	conn.setDoOutput(true);
	conn.setUseCaches(false);
	conn.setChunkedStreamingMode(0);
	conn.setRequestMethod("POST");
	conn.setRequestProperty("Content-Type",
	"application/x-www-form-urlencoded;charset=UTF-8");
	conn.setRequestProperty("Content-Length",
	Integer.toString(body.length()));
	// post the request
	OutputStream out = conn.getOutputStream();
	out.write(body.getBytes());
	out.close();
	// handle the response
	int status = conn.getResponseCode();
	if (status != 200) {
	throw new IOException("Post failed with error code " + status);
	}
	} finally {
	if (conn != null) {
	conn.disconnect();
	}
	}
	}
	}