[Omaha] Move most functionality to OmahaBase, add JobService

chrome/android/java/src/org/chromium/chrome/browser/omaha/OmahaClient.java

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.chrome.browser.omaha;
 
 import android.app.IntentService;
 import android.content.Context;
 import android.content.Intent;
-import android.content.SharedPreferences;
-import android.os.Build;
-import android.support.annotation.IntDef;
-
-import org.chromium.base.Log;
-import org.chromium.base.ThreadUtils;
-import org.chromium.base.VisibleForTesting;
-
-import java.io.IOException;
-import java.lang.annotation.Retention;
-import java.lang.annotation.RetentionPolicy;
-import java.net.HttpURLConnection;
-import java.net.MalformedURLException;
-import java.net.URL;
-import java.util.concurrent.TimeUnit;
 
 /**
- * Keeps tabs on the current state of Chrome, tracking if and when a request should be sent to the
- * Omaha Server.
- *
- * A hook in ChromeActivity's doDeferredResume() initializes the service.  Further attempts to
- * reschedule events will be scheduled by the class itself.
- *
- * Each request to the server will perform an update check and ping the server.
- * We use a repeating alarm to schedule the XML requests to be generated 5 hours apart.
- * If Chrome isn't running when the alarm is fired, the request generation will be stalled until
- * the next time Chrome runs.
- *
- * mevissen suggested being conservative with our timers for sending requests.
- * POST attempts that fail to be acknowledged by the server are re-attempted, with at least
- * one hour between each attempt.
- *
- * Status is saved directly to the the disk after every operation.  Unit tests testing the code
- * paths without using Intents may need to call restoreState() manually as it is not automatically
- * handled in onCreate().
- *
- * Implementation notes:
- * http://docs.google.com/a/google.com/document/d/1scTCovqASf5ktkOeVj8wFRkWTCeDYw2LrOBNn05CDB0/edit
+ * Runs the {@link OmahaBase} pipeline as a {@link IntentService}.
  *
  * NOTE: This class can never be renamed because the user may have Intents floating around that
  *       reference this class specifically.
  */
 public class OmahaClient extends IntentService {
-    // Results of {@link #handlePostRequest()}.
-    @Retention(RetentionPolicy.SOURCE)
-    @IntDef({POST_RESULT_NO_REQUEST, POST_RESULT_SENT, POST_RESULT_FAILED, POST_RESULT_SCHEDULED})
-    @interface PostResult {}
-    static final int POST_RESULT_NO_REQUEST = 0;
-    static final int POST_RESULT_SENT = 1;
-    static final int POST_RESULT_FAILED = 2;
-    static final int POST_RESULT_SCHEDULED = 3;
-
     private static final String TAG = "omaha";
 
-    /** Deprecated; kept around to cancel alarms set for OmahaClient pre-M58. */
-    private static final String ACTION_REGISTER_REQUEST =
-            "org.chromium.chrome.browser.omaha.ACTION_REGISTER_REQUEST";
-
-    // Delays between events.
-    static final long MS_POST_BASE_DELAY = TimeUnit.HOURS.toMillis(1);
-    static final long MS_POST_MAX_DELAY = TimeUnit.HOURS.toMillis(5);
-    static final long MS_BETWEEN_REQUESTS = TimeUnit.HOURS.toMillis(5);
-    static final int MS_CONNECTION_TIMEOUT = (int) TimeUnit.MINUTES.toMillis(1);
-
-    // Strings indicating how the Chrome APK arrived on the user's device. These values MUST NOT
-    // be changed without updating the corresponding Omaha server strings.
-    static final String INSTALL_SOURCE_SYSTEM = "system_image";
-    static final String INSTALL_SOURCE_ORGANIC = "organic";
-
-    private static final long INVALID_TIMESTAMP = -1;
-    @VisibleForTesting
-    static final String INVALID_REQUEST_ID = "invalid";
-
-    // Member fields not persisted to disk.
-    private boolean mStateHasBeenRestored;
-    private OmahaDelegate mDelegate;
-
-    // State saved written to and read from disk.
-    private RequestData mCurrentRequest;
-    private long mTimestampOfInstall;
-    private long mTimestampForNextPostAttempt;
-    private long mTimestampForNewRequest;
-    private String mLatestVersion;
-    private String mMarketURL;
-    private String mInstallSource;
-    protected boolean mSendInstallEvent;
-
     public OmahaClient() {
         super(TAG);
         setIntentRedelivery(true);
     }
 
-    /**
-     * Handles an action on a thread separate from the UI thread.
-     * @param intent Intent fired by some part of Chrome.
-     */
     @Override
     public void onHandleIntent(Intent intent) {
-        assert !ThreadUtils.runningOnUiThread();
-        run();
+        OmahaService.getInstance(this).run();
     }
 
-    protected void run() {
-        if (mDelegate == null) mDelegate = new OmahaDelegateImpl(this);
-
-        if (OmahaBase.isDisabled() || Build.VERSION.SDK_INT > Build.VERSION_CODES.N
-                || getRequestGenerator() == null) {
-            Log.v(TAG, "Disabled.  Ignoring intent.");
-            return;
-        }
-
-        restoreState(getContext());
-
-        long nextTimestamp = Long.MAX_VALUE;
-        if (mDelegate.isChromeBeingUsed()) {
-            handleRegisterActiveRequest();
-            nextTimestamp = Math.min(nextTimestamp, mTimestampForNewRequest);
-        }
-
-        if (hasRequest()) {
-            int result = handlePostRequest();
-            if (result == POST_RESULT_FAILED || result == POST_RESULT_SCHEDULED) {
-                nextTimestamp = Math.min(nextTimestamp, mTimestampForNextPostAttempt);
-            }
-        }
-
-        // TODO(dfalcantara): Prevent Omaha code from repeatedly rescheduling itself immediately in
-        //                    case a scheduling error occurs.
-        if (nextTimestamp != Long.MAX_VALUE && nextTimestamp >= 0) {
-            mDelegate.scheduleService(this, nextTimestamp);
-        }
-        saveState(getContext());
-    }
-
-    /**
-     * Begin communicating with the Omaha Update Server.
-     */
-    static void startService(Context context) {
-        context.startService(createOmahaIntent(context));
-    }
-
-    static Intent createOmahaIntent(Context context) {
+    static Intent createIntent(Context context) {
         return new Intent(context, OmahaClient.class);
     }
-
-    /**
-     * Determines if a new request should be generated.  New requests are only generated if enough
-     * time has passed between now and the last time a request was generated.
-     */
-    private void handleRegisterActiveRequest() {
-        // If the current request is too old, generate a new one.
-        long currentTimestamp = getBackoffScheduler().getCurrentTime();
-        boolean isTooOld = hasRequest()
-                && mCurrentRequest.getAgeInMilliseconds(currentTimestamp) >= MS_BETWEEN_REQUESTS;
-        boolean isOverdue = currentTimestamp >= mTimestampForNewRequest;
-        if (isTooOld || isOverdue) {
-            registerNewRequest(currentTimestamp);
-        }
-    }
-
-    /**
-     * Sends the request it is holding.
-     */
-    private int handlePostRequest() {
-        if (!hasRequest()) {
-            mDelegate.onHandlePostRequestDone(POST_RESULT_NO_REQUEST, false);
-            return POST_RESULT_NO_REQUEST;
-        }
-
-        // If enough time has passed since the last attempt, try sending a request.
-        int result;
-        long currentTimestamp = getBackoffScheduler().getCurrentTime();
-        boolean installEventWasSent = false;
-        if (currentTimestamp >= mTimestampForNextPostAttempt) {
-            // All requests made during the same session should have the same ID.
-            String sessionID = mDelegate.generateUUID();
-            boolean sendingInstallRequest = mSendInstallEvent;
-            boolean succeeded = generateAndPostRequest(currentTimestamp, sessionID);
-
-            if (succeeded && sendingInstallRequest) {
-                // Only the first request ever generated should contain an install event.
-                mSendInstallEvent = false;
-                installEventWasSent = true;
-
-                // Create and immediately send another request for a ping and update check.
-                registerNewRequest(currentTimestamp);
-                succeeded &= generateAndPostRequest(currentTimestamp, sessionID);
-            }
-
-            result = succeeded ? POST_RESULT_SENT : POST_RESULT_FAILED;
-        } else {
-            result = POST_RESULT_SCHEDULED;
-        }
-
-        mDelegate.onHandlePostRequestDone(result, installEventWasSent);
-        return result;
-    }
-
-    private boolean generateAndPostRequest(long currentTimestamp, String sessionID) {
-        ExponentialBackoffScheduler scheduler = getBackoffScheduler();
-        boolean succeeded = false;
-        try {
-            // Generate the XML for the current request.
-            long installAgeInDays = RequestGenerator.installAge(currentTimestamp,
-                    mTimestampOfInstall, mCurrentRequest.isSendInstallEvent());
-            String version = VersionNumberGetter.getInstance().getCurrentlyUsedVersion(this);
-            String xml = getRequestGenerator().generateXML(
-                    sessionID, version, installAgeInDays, mCurrentRequest);
-
-            // Send the request to the server & wait for a response.
-            String response = postRequest(currentTimestamp, xml);
-
-            // Parse out the response.
-            String appId = getRequestGenerator().getAppId();
-            boolean sentPingAndUpdate = !mSendInstallEvent;
-            ResponseParser parser = new ResponseParser(
-                    appId, mSendInstallEvent, sentPingAndUpdate, sentPingAndUpdate);
-            parser.parseResponse(response);
-            mLatestVersion = parser.getNewVersion();
-            mMarketURL = parser.getURL();
-
-            succeeded = true;
-        } catch (RequestFailureException e) {
-            Log.e(TAG, "Failed to contact server: ", e);
-        }
-
-        if (succeeded) {
-            // If we've gotten this far, we've successfully sent a request.
-            mCurrentRequest = null;
-
-            scheduler.resetFailedAttempts();
-            mTimestampForNewRequest = scheduler.getCurrentTime() + MS_BETWEEN_REQUESTS;
-            mTimestampForNextPostAttempt = scheduler.calculateNextTimestamp();
-            Log.i(TAG, "Request to Server Successful. Timestamp for next request:"
-                    + String.valueOf(mTimestampForNextPostAttempt));
-        } else {
-            // Set the alarm to try again later.  Failures are incremented after setting the timer
-            // to allow the first failure to incur the minimum base delay between POSTs.
-            mTimestampForNextPostAttempt = scheduler.calculateNextTimestamp();
-            scheduler.increaseFailedAttempts();
-        }
-
-        mDelegate.onGenerateAndPostRequestDone(succeeded);
-        return succeeded;
-    }
-
-    /**
-     * Registers a new request with the current timestamp.  Internal timestamps are reset to start
-     * fresh.
-     * @param currentTimestamp Current time.
-     */
-    private void registerNewRequest(long currentTimestamp) {
-        mCurrentRequest = createRequestData(currentTimestamp, null);
-        getBackoffScheduler().resetFailedAttempts();
-        mTimestampForNextPostAttempt = currentTimestamp;
-
-        // Tentatively set the timestamp for a new request.  This will be updated when the server
-        // is successfully contacted.
-        mTimestampForNewRequest = currentTimestamp + MS_BETWEEN_REQUESTS;
-
-        mDelegate.onRegisterNewRequestDone(mTimestampForNewRequest, mTimestampForNextPostAttempt);
-    }
-
-    private RequestData createRequestData(long currentTimestamp, String persistedID) {
-        // If we're sending a persisted event, keep trying to send the same request ID.
-        String requestID;
-        if (persistedID == null || INVALID_REQUEST_ID.equals(persistedID)) {
-            requestID = mDelegate.generateUUID();
-        } else {
-            requestID = persistedID;
-        }
-        return new RequestData(mSendInstallEvent, currentTimestamp, requestID, mInstallSource);
-    }
-
-    private boolean hasRequest() {
-        return mCurrentRequest != null;
-    }
-
-    /**
-     * Posts the request to the Omaha server.
-     * @return the XML response as a String.
-     * @throws RequestFailureException if the request fails.
-     */
-    private String postRequest(long timestamp, String xml) throws RequestFailureException {
-        String response = null;
-
-        HttpURLConnection urlConnection = null;
-        try {
-            urlConnection = createConnection();
-
-            // Prepare the HTTP header.
-            urlConnection.setDoOutput(true);
-            urlConnection.setFixedLengthStreamingMode(xml.getBytes().length);
-            if (mSendInstallEvent && getBackoffScheduler().getNumFailedAttempts() > 0) {
-                String age = Long.toString(mCurrentRequest.getAgeInSeconds(timestamp));
-                urlConnection.addRequestProperty("X-RequestAge", age);
-            }
-
-            response = OmahaBase.sendRequestToServer(urlConnection, xml);
-        } catch (IllegalAccessError e) {
-            throw new RequestFailureException("Caught an IllegalAccessError:", e);
-        } catch (IllegalArgumentException e) {
-            throw new RequestFailureException("Caught an IllegalArgumentException:", e);
-        } catch (IllegalStateException e) {
-            throw new RequestFailureException("Caught an IllegalStateException:", e);
-        } finally {
-            if (urlConnection != null) {
-                urlConnection.disconnect();
-            }
-        }
-
-        return response;
-    }
-
-    /**
-     * Returns a HttpURLConnection to the server.
-     */
-    @VisibleForTesting
-    protected HttpURLConnection createConnection() throws RequestFailureException {
-        try {
-            URL url = new URL(getRequestGenerator().getServerUrl());
-            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
-            connection.setConnectTimeout(MS_CONNECTION_TIMEOUT);
-            connection.setReadTimeout(MS_CONNECTION_TIMEOUT);
-            return connection;
-        } catch (MalformedURLException e) {
-            throw new RequestFailureException("Caught a malformed URL exception.", e);
-        } catch (IOException e) {
-            throw new RequestFailureException("Failed to open connection to URL", e);
-        }
-    }
-
-    /**
-     * Reads the data back from the file it was saved to.  Uses SharedPreferences to handle I/O.
-     * Sanity checks are performed on the timestamps to guard against clock changing.
-     */
-    @VisibleForTesting
-    void restoreState(Context context) {
-        if (mStateHasBeenRestored) return;
-
-        String installSource =
-                mDelegate.isInSystemImage() ? INSTALL_SOURCE_SYSTEM : INSTALL_SOURCE_ORGANIC;
-        ExponentialBackoffScheduler scheduler = getBackoffScheduler();
-        long currentTime = scheduler.getCurrentTime();
-
-        SharedPreferences preferences = OmahaBase.getSharedPreferences(context);
-        mTimestampForNewRequest =
-                preferences.getLong(OmahaBase.PREF_TIMESTAMP_FOR_NEW_REQUEST, currentTime);
-        mTimestampForNextPostAttempt =
-                preferences.getLong(OmahaBase.PREF_TIMESTAMP_FOR_NEXT_POST_ATTEMPT, currentTime);
-        mTimestampOfInstall = preferences.getLong(OmahaBase.PREF_TIMESTAMP_OF_INSTALL, currentTime);
-        mSendInstallEvent = preferences.getBoolean(OmahaBase.PREF_SEND_INSTALL_EVENT, true);
-        mInstallSource = preferences.getString(OmahaBase.PREF_INSTALL_SOURCE, installSource);
-        mLatestVersion = preferences.getString(OmahaBase.PREF_LATEST_VERSION, "");
-        mMarketURL = preferences.getString(OmahaBase.PREF_MARKET_URL, "");
-
-        // If we're not sending an install event, don't bother restoring the request ID:
-        // the server does not expect to have persisted request IDs for pings or update checks.
-        String persistedRequestId = mSendInstallEvent
-                ? preferences.getString(OmahaBase.PREF_PERSISTED_REQUEST_ID, INVALID_REQUEST_ID)
-                : INVALID_REQUEST_ID;
-        long requestTimestamp =
-                preferences.getLong(OmahaBase.PREF_TIMESTAMP_OF_REQUEST, INVALID_TIMESTAMP);
-        mCurrentRequest = requestTimestamp == INVALID_TIMESTAMP
-                ? null : createRequestData(requestTimestamp, persistedRequestId);
-
-        // Confirm that the timestamp for the next request is less than the base delay.
-        long delayToNewRequest = mTimestampForNewRequest - currentTime;
-        if (delayToNewRequest > MS_BETWEEN_REQUESTS) {
-            Log.w(TAG, "Delay to next request (" + delayToNewRequest
-                    + ") is longer than expected.  Resetting to now.");
-            mTimestampForNewRequest = currentTime;
-        }
-
-        // Confirm that the timestamp for the next POST is less than the current delay.
-        long delayToNextPost = mTimestampForNextPostAttempt - currentTime;
-        long lastGeneratedDelay = scheduler.getGeneratedDelay();
-        if (delayToNextPost > lastGeneratedDelay) {
-            Log.w(TAG, "Delay to next post attempt (" + delayToNextPost
-                            + ") is greater than expected (" + lastGeneratedDelay
-                            + ").  Resetting to now.");
-            mTimestampForNextPostAttempt = currentTime;
-        }
-
-        migrateToNewerChromeVersions();
-        mStateHasBeenRestored = true;
-    }
-
-    /**
-     * Writes out the current state to a file.
-     */
-    private void saveState(Context context) {
-        SharedPreferences prefs = OmahaBase.getSharedPreferences(context);
-        SharedPreferences.Editor editor = prefs.edit();
-        editor.putBoolean(OmahaBase.PREF_SEND_INSTALL_EVENT, mSendInstallEvent);
-        editor.putLong(OmahaBase.PREF_TIMESTAMP_OF_INSTALL, mTimestampOfInstall);
-        editor.putLong(
-                OmahaBase.PREF_TIMESTAMP_FOR_NEXT_POST_ATTEMPT, mTimestampForNextPostAttempt);
-        editor.putLong(OmahaBase.PREF_TIMESTAMP_FOR_NEW_REQUEST, mTimestampForNewRequest);
-        editor.putLong(OmahaBase.PREF_TIMESTAMP_OF_REQUEST,
-                hasRequest() ? mCurrentRequest.getCreationTimestamp() : INVALID_TIMESTAMP);
-        editor.putString(OmahaBase.PREF_PERSISTED_REQUEST_ID,
-                hasRequest() ? mCurrentRequest.getRequestID() : INVALID_REQUEST_ID);
-        editor.putString(
-                OmahaBase.PREF_LATEST_VERSION, mLatestVersion == null ? "" : mLatestVersion);
-        editor.putString(OmahaBase.PREF_MARKET_URL, mMarketURL == null ? "" : mMarketURL);
-        editor.putString(OmahaBase.PREF_INSTALL_SOURCE, mInstallSource);
-        editor.apply();
-
-        mDelegate.onSaveStateDone(mTimestampForNewRequest, mTimestampForNextPostAttempt);
-    }
-
-    private void migrateToNewerChromeVersions() {
-        // Remove any repeating alarms in favor of the new scheduling setup on M58 and up.
-        // Seems cheaper to cancel the alarm repeatedly than to store a SharedPreference and never
-        // do it again.
-        Intent intent = new Intent(getContext(), OmahaClient.class);
-        intent.setAction(ACTION_REGISTER_REQUEST);
-        getBackoffScheduler().cancelAlarm(intent);
-    }
-
-    Context getContext() {
-        return mDelegate.getContext();
-    }
-
-    private RequestGenerator getRequestGenerator() {
-        return mDelegate.getRequestGenerator();
-    }
-
-    private ExponentialBackoffScheduler getBackoffScheduler() {
-        return mDelegate.getScheduler();
-    }
-
-    void setDelegateForTests(OmahaDelegate delegate) {
-        mDelegate = delegate;
-    }
 }