Massive refactor of the Android invalidation code.

sync/android/java/src/org/chromium/sync/notifier/InvalidationService.java

Index: sync/android/java/src/org/chromium/sync/notifier/InvalidationService.java
diff --git a/sync/android/java/src/org/chromium/sync/notifier/InvalidationService.java b/sync/android/java/src/org/chromium/sync/notifier/InvalidationService.java
deleted file mode 100644
index 37a8e6a8fdb0bb1e7ffbdc5613b786f176f37941..0000000000000000000000000000000000000000
--- a/sync/android/java/src/org/chromium/sync/notifier/InvalidationService.java
+++ /dev/null
@@ -1,507 +0,0 @@
-// Copyright 2013 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.sync.notifier;
-
-import android.accounts.Account;
-import android.app.PendingIntent;
-import android.content.ContentResolver;
-import android.content.Intent;
-import android.os.Bundle;
-import android.util.Log;
-
-import com.google.common.annotations.VisibleForTesting;
-import com.google.ipc.invalidation.external.client.InvalidationListener.RegistrationState;
-import com.google.ipc.invalidation.external.client.contrib.AndroidListener;
-import com.google.ipc.invalidation.external.client.types.ErrorInfo;
-import com.google.ipc.invalidation.external.client.types.Invalidation;
-import com.google.ipc.invalidation.external.client.types.ObjectId;
-import com.google.protos.ipc.invalidation.Types.ClientType;
-
-import org.chromium.base.ApplicationStatus;
-import org.chromium.base.CollectionUtil;
-import org.chromium.sync.internal_api.pub.base.ModelType;
-import org.chromium.sync.notifier.InvalidationPreferences.EditContext;
-import org.chromium.sync.signin.AccountManagerHelper;
-import org.chromium.sync.signin.ChromeSigninController;
-
-import java.util.Collections;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Random;
-import java.util.Set;
-
-import javax.annotation.Nullable;
-
-/**
- * Service that controls notifications for sync.
- * <p>
- * This service serves two roles. On the one hand, it is a client for the notification system
- * used to trigger sync. It receives invalidations and converts them into
- * {@link ContentResolver#requestSync} calls, and it supplies the notification system with the set
- * of desired registrations when requested.
- * <p>
- * On the other hand, this class is controller for the notification system. It starts it and stops
- * it, and it requests that it perform (un)registrations as the set of desired sync types changes.
- * <p>
- * This class is an {@code IntentService}. All methods are assumed to be executing on its single
- * execution thread.
- *
- * @author dsmyers@google.com
- */
-public class InvalidationService extends AndroidListener {
-    /* This class must be public because it is exposed as a service. */
-
-    /** Notification client typecode. */
-    @VisibleForTesting
-    static final int CLIENT_TYPE = ClientType.Type.CHROME_SYNC_ANDROID_VALUE;
-
-    private static final String TAG = "InvalidationService";
-
-    private static final Random RANDOM = new Random();
-
-    /**
-     * Whether the underlying notification client has been started. This boolean is updated when a
-     * start or stop intent is issued to the underlying client, not when the intent is actually
-     * processed.
-     */
-    private static boolean sIsClientStarted;
-
-    /**
-     * The id of the client in use, if any. May be {@code null} if {@link #sIsClientStarted} is
-     * true if the client has not yet gone ready.
-     */
-    @Nullable private static byte[] sClientId;
-
-    @Override
-    public void onHandleIntent(Intent intent) {
-        // Ensure that a client is or is not running, as appropriate, and that it is for the
-        // correct account. ensureAccount will stop the client if account is non-null and doesn't
-        // match the stored account. Then, if a client should be running, ensureClientStartState
-        // will start a new one if needed. I.e., these two functions work together to restart the
-        // client when the account changes.
-        Account account = intent.hasExtra(InvalidationIntentProtocol.EXTRA_ACCOUNT) ?
-                (Account) intent.getParcelableExtra(InvalidationIntentProtocol.EXTRA_ACCOUNT)
-                : null;
-
-        ensureAccount(account);
-        ensureClientStartState();
-
-        // Handle the intent.
-        if (InvalidationIntentProtocol.isStop(intent) && sIsClientStarted) {
-            // If the intent requests that the client be stopped, stop it.
-            stopClient();
-        } else if (InvalidationIntentProtocol.isRegisteredTypesChange(intent)) {
-            // If the intent requests a change in registrations, change them.
-            List<String> regTypes = intent.getStringArrayListExtra(
-                    InvalidationIntentProtocol.EXTRA_REGISTERED_TYPES);
-            setRegisteredTypes(regTypes != null ? new HashSet<String>(regTypes) : null,
-                    InvalidationIntentProtocol.getRegisteredObjectIds(intent));
-        } else {
-            // Otherwise, we don't recognize the intent. Pass it to the notification client service.
-            super.onHandleIntent(intent);
-        }
-    }
-
-    @Override
-    public void invalidate(Invalidation invalidation, byte[] ackHandle) {
-        byte[] payload = invalidation.getPayload();
-        String payloadStr = (payload == null) ? null : new String(payload);
-        requestSync(invalidation.getObjectId(), invalidation.getVersion(), payloadStr);
-        acknowledge(ackHandle);
-    }
-
-    @Override
-    public void invalidateUnknownVersion(ObjectId objectId, byte[] ackHandle) {
-        requestSync(objectId, null, null);
-        acknowledge(ackHandle);
-    }
-
-    @Override
-    public void invalidateAll(byte[] ackHandle) {
-        requestSync(null, null, null);
-        acknowledge(ackHandle);
-    }
-
-    @Override
-    public void informRegistrationFailure(
-            byte[] clientId, ObjectId objectId, boolean isTransient, String errorMessage) {
-        Log.w(TAG, "Registration failure on " + objectId + " ; transient = " + isTransient
-                + ": " + errorMessage);
-        if (isTransient) {
-          // Retry immediately on transient failures. The base AndroidListener will handle
-          // exponential backoff if there are repeated failures.
-            List<ObjectId> objectIdAsList = CollectionUtil.newArrayList(objectId);
-            if (readRegistrationsFromPrefs().contains(objectId)) {
-                register(clientId, objectIdAsList);
-            } else {
-                unregister(clientId, objectIdAsList);
-            }
-        }
-    }
-
-    @Override
-    public void informRegistrationStatus(
-            byte[] clientId, ObjectId objectId, RegistrationState regState) {
-        Log.d(TAG, "Registration status for " + objectId + ": " + regState);
-        List<ObjectId> objectIdAsList = CollectionUtil.newArrayList(objectId);
-        boolean registrationisDesired = readRegistrationsFromPrefs().contains(objectId);
-        if (regState == RegistrationState.REGISTERED) {
-            if (!registrationisDesired) {
-                Log.i(TAG, "Unregistering for object we're no longer interested in");
-                unregister(clientId, objectIdAsList);
-            }
-        } else {
-            if (registrationisDesired) {
-                Log.i(TAG, "Registering for an object");
-                register(clientId, objectIdAsList);
-            }
-        }
-    }
-
-    @Override
-    public void informError(ErrorInfo errorInfo) {
-        Log.w(TAG, "Invalidation client error:" + errorInfo);
-        if (!errorInfo.isTransient() && sIsClientStarted) {
-            // It is important not to stop the client if it is already stopped. Otherwise, the
-            // possibility exists to go into an infinite loop if the stop call itself triggers an
-            // error (e.g., because no client actually exists).
-            stopClient();
-        }
-    }
-
-    @Override
-    public void ready(byte[] clientId) {
-        setClientId(clientId);
-
-        // We might have accumulated some registrations to do while we were waiting for the client
-        // to become ready.
-        reissueRegistrations(clientId);
-    }
-
-    @Override
-    public void reissueRegistrations(byte[] clientId) {
-        Set<ObjectId> desiredRegistrations = readRegistrationsFromPrefs();
-        if (!desiredRegistrations.isEmpty()) {
-            register(clientId, desiredRegistrations);
-        }
-    }
-
-    @Override
-    public void requestAuthToken(final PendingIntent pendingIntent,
-            @Nullable String invalidAuthToken) {
-        @Nullable Account account = ChromeSigninController.get(this).getSignedInUser();
-        if (account == null) {
-            // This should never happen, because this code should only be run if a user is
-            // signed-in.
-            Log.w(TAG, "No signed-in user; cannot send message to data center");
-            return;
-        }
-
-        // Attempt to retrieve a token for the user. This method will also invalidate
-        // invalidAuthToken if it is non-null.
-        AccountManagerHelper.get(this).getNewAuthTokenFromForeground(
-                account, invalidAuthToken, getOAuth2ScopeWithType(),
-                new AccountManagerHelper.GetAuthTokenCallback() {
-                    @Override
-                    public void tokenAvailable(String token) {
-                        if (token != null) {
-                            setAuthToken(InvalidationService.this.getApplicationContext(),
-                                    pendingIntent, token, getOAuth2ScopeWithType());
-                        }
-                    }
-                });
-    }
-
-    @Override
-    public void writeState(byte[] data) {
-        InvalidationPreferences invPreferences = new InvalidationPreferences(this);
-        EditContext editContext = invPreferences.edit();
-        invPreferences.setInternalNotificationClientState(editContext, data);
-        invPreferences.commit(editContext);
-    }
-
-    @Override
-    @Nullable public byte[] readState() {
-        return new InvalidationPreferences(this).getInternalNotificationClientState();
-    }
-
-    /**
-     * Ensures that the client is running or not running as appropriate, based on the value of
-     * {@link #shouldClientBeRunning}.
-     */
-    private void ensureClientStartState() {
-        final boolean shouldClientBeRunning = shouldClientBeRunning();
-        if (!shouldClientBeRunning && sIsClientStarted) {
-            // Stop the client if it should not be running and is.
-            stopClient();
-        } else if (shouldClientBeRunning && !sIsClientStarted) {
-            // Start the client if it should be running and isn't.
-            startClient();
-        }
-    }
-
-    /**
-     * If {@code intendedAccount} is non-{@null} and differs from the account stored in preferences,
-     * then stops the existing client (if any) and updates the stored account.
-     */
-    private void ensureAccount(@Nullable Account intendedAccount) {
-        if (intendedAccount == null) {
-            return;
-        }
-        InvalidationPreferences invPrefs = new InvalidationPreferences(this);
-        if (!intendedAccount.equals(invPrefs.getSavedSyncedAccount())) {
-            if (sIsClientStarted) {
-                stopClient();
-            }
-            setAccount(intendedAccount);
-        }
-    }
-
-    /**
-     * Starts a new client, destroying any existing client. {@code owningAccount} is the account
-     * of the user for which the client is being created; it will be persisted using
-     * {@link InvalidationPreferences#setAccount}.
-     */
-    private void startClient() {
-        byte[] clientName = InvalidationClientNameProvider.get().getInvalidatorClientName();
-        Intent startIntent = AndroidListener.createStartIntent(this, CLIENT_TYPE, clientName);
-        startService(startIntent);
-        setIsClientStarted(true);
-    }
-
-    /** Stops the notification client. */
-    private void stopClient() {
-        startService(AndroidListener.createStopIntent(this));
-        setIsClientStarted(false);
-        setClientId(null);
-    }
-
-    /** Sets the saved sync account in {@link InvalidationPreferences} to {@code owningAccount}. */
-    private void setAccount(Account owningAccount) {
-        InvalidationPreferences invPrefs = new InvalidationPreferences(this);
-        EditContext editContext = invPrefs.edit();
-        invPrefs.setAccount(editContext, owningAccount);
-        invPrefs.commit(editContext);
-    }
-
-    /**
-     * Reads the saved sync types from storage (if any) and returns a set containing the
-     * corresponding object ids.
-     */
-    private Set<ObjectId> readSyncRegistrationsFromPrefs() {
-        Set<String> savedTypes = new InvalidationPreferences(this).getSavedSyncedTypes();
-        if (savedTypes == null) return Collections.emptySet();
-        else return ModelType.syncTypesToObjectIds(savedTypes);
-    }
-
-    /**
-     * Reads the saved non-sync object ids from storage (if any) and returns a set containing the
-     * corresponding object ids.
-     */
-    private Set<ObjectId> readNonSyncRegistrationsFromPrefs() {
-        Set<ObjectId> objectIds = new InvalidationPreferences(this).getSavedObjectIds();
-        if (objectIds == null) return Collections.emptySet();
-        else return objectIds;
-    }
-
-    /**
-     * Reads the object registrations from storage (if any) and returns a set containing the
-     * corresponding object ids.
-     */
-    @VisibleForTesting
-    Set<ObjectId> readRegistrationsFromPrefs() {
-        return joinRegistrations(readSyncRegistrationsFromPrefs(),
-                readNonSyncRegistrationsFromPrefs());
-    }
-
-    /**
-     * Join Sync object registrations with non-Sync object registrations to get the full set of
-     * desired object registrations.
-     */
-    private static Set<ObjectId> joinRegistrations(Set<ObjectId> syncRegistrations,
-                                                   Set<ObjectId> nonSyncRegistrations) {
-        if (nonSyncRegistrations.isEmpty()) {
-            return syncRegistrations;
-        }
-        if (syncRegistrations.isEmpty()) {
-            return nonSyncRegistrations;
-        }
-        Set<ObjectId> registrations = new HashSet<ObjectId>(
-                syncRegistrations.size() + nonSyncRegistrations.size());
-        registrations.addAll(syncRegistrations);
-        registrations.addAll(nonSyncRegistrations);
-        return registrations;
-    }
-
-    /**
-     * Sets the types for which notifications are required to {@code syncTypes}. {@code syncTypes}
-     * is either a list of specific types or the special wildcard type
-     * {@link ModelType#ALL_TYPES_TYPE}. Also registers for additional objects specified by
-     * {@code objectIds}. Either parameter may be null if the corresponding registrations are not
-     * changing.
-     * <p>
-     * @param syncTypes
-     */
-    private void setRegisteredTypes(Set<String> syncTypes, Set<ObjectId> objectIds) {
-        // If we have a ready client and will be making registration change calls on it, then
-        // read the current registrations from preferences before we write the new values, so that
-        // we can take the diff of the two registration sets and determine which registration change
-        // calls to make.
-        Set<ObjectId> existingSyncRegistrations = (sClientId == null) ?
-                null : readSyncRegistrationsFromPrefs();
-        Set<ObjectId> existingNonSyncRegistrations = (sClientId == null) ?
-                null : readNonSyncRegistrationsFromPrefs();
-
-        // Write the new sync types/object ids to preferences. We do not expand the syncTypes to
-        // take into account the ALL_TYPES_TYPE at this point; we want to persist the wildcard
-        // unexpanded.
-        InvalidationPreferences prefs = new InvalidationPreferences(this);
-        EditContext editContext = prefs.edit();
-        if (syncTypes != null) {
-            prefs.setSyncTypes(editContext, syncTypes);
-        }
-        if (objectIds != null) {
-            prefs.setObjectIds(editContext, objectIds);
-        }
-        prefs.commit(editContext);
-
-        // If we do not have a ready invalidation client, we cannot change its registrations, so
-        // return. Later, when the client is ready, we will supply the new registrations.
-        if (sClientId == null) {
-            return;
-        }
-
-        // We do have a ready client. Unregister any existing registrations not present in the
-        // new set and register any elements in the new set not already present. This call does
-        // expansion of the ALL_TYPES_TYPE wildcard.
-        // NOTE: syncTypes MUST NOT be used below this line, since it contains an unexpanded
-        // wildcard.
-        // When computing the desired set of object ids, if only sync types were provided, then
-        // keep the existing non-sync types, and vice-versa.
-        Set<ObjectId> desiredSyncRegistrations = syncTypes != null ?
-                ModelType.syncTypesToObjectIds(syncTypes) : existingSyncRegistrations;
-        Set<ObjectId> desiredNonSyncRegistrations = objectIds != null ?
-                objectIds : existingNonSyncRegistrations;
-        Set<ObjectId> desiredRegistrations = joinRegistrations(desiredNonSyncRegistrations,
-                desiredSyncRegistrations);
-        Set<ObjectId> existingRegistrations = joinRegistrations(existingNonSyncRegistrations,
-                existingSyncRegistrations);
-
-        Set<ObjectId> unregistrations = new HashSet<ObjectId>();
-        Set<ObjectId> registrations = new HashSet<ObjectId>();
-        computeRegistrationOps(existingRegistrations, desiredRegistrations,
-                registrations, unregistrations);
-        unregister(sClientId, unregistrations);
-        register(sClientId, registrations);
-    }
-
-    /**
-     * Computes the set of (un)registrations to perform so that the registrations active in the
-     * Ticl will be {@code desiredRegs}, given that {@existingRegs} already exist.
-     *
-     * @param regAccumulator registrations to perform
-     * @param unregAccumulator unregistrations to perform.
-     */
-    @VisibleForTesting
-    static void computeRegistrationOps(Set<ObjectId> existingRegs, Set<ObjectId> desiredRegs,
-            Set<ObjectId> regAccumulator, Set<ObjectId> unregAccumulator) {
-
-        // Registrations to do are elements in the new set but not the old set.
-        regAccumulator.addAll(desiredRegs);
-        regAccumulator.removeAll(existingRegs);
-
-        // Unregistrations to do are elements in the old set but not the new set.
-        unregAccumulator.addAll(existingRegs);
-        unregAccumulator.removeAll(desiredRegs);
-    }
-
-    /**
-     * Requests that the sync system perform a sync.
-     *
-     * @param objectId the object that changed, if known.
-     * @param version the version of the object that changed, if known.
-     * @param payload the payload of the change, if known.
-     */
-    private void requestSync(@Nullable ObjectId objectId, @Nullable Long version,
-            @Nullable String payload) {
-        // Construct the bundle to supply to the native sync code.
-        Bundle bundle = new Bundle();
-        if (objectId == null && version == null && payload == null) {
-            // Use an empty bundle in this case for compatibility with the v1 implementation.
-        } else {
-            if (objectId != null) {
-                bundle.putInt("objectSource", objectId.getSource());
-                bundle.putString("objectId", new String(objectId.getName()));
-            }
-            // We use "0" as the version if we have an unknown-version invalidation. This is OK
-            // because the native sync code special-cases zero and always syncs for invalidations at
-            // that version (Tango defines a special UNKNOWN_VERSION constant with this value).
-            bundle.putLong("version", (version == null) ? 0 : version);
-            bundle.putString("payload", (payload == null) ? "" : payload);
-        }
-        Account account = ChromeSigninController.get(this).getSignedInUser();
-        String contractAuthority = SyncStatusHelper.get(this).getContractAuthority();
-        requestSyncFromContentResolver(bundle, account, contractAuthority);
-    }
-
-    /**
-     * Calls {@link ContentResolver#requestSync(Account, String, Bundle)} to trigger a sync. Split
-     * into a separate method so that it can be overriden in tests.
-     */
-    @VisibleForTesting
-    void requestSyncFromContentResolver(
-            Bundle bundle, Account account, String contractAuthority) {
-        Log.d(TAG, "Request sync: " + account + " / " + contractAuthority + " / "
-            + bundle.keySet());
-        ContentResolver.requestSync(account, contractAuthority, bundle);
-    }
-
-    /**
-     * Returns whether the notification client should be running, i.e., whether Chrome is in the
-     * foreground and sync is enabled.
-     */
-    @VisibleForTesting
-    boolean shouldClientBeRunning() {
-        return isSyncEnabled() && isChromeInForeground();
-    }
-
-    /** Returns whether sync is enabled. LLocal method so it can be overridden in tests. */
-    @VisibleForTesting
-    boolean isSyncEnabled() {
-        return SyncStatusHelper.get(getApplicationContext()).isSyncEnabled();
-    }
-
-    /**
-     * Returns whether Chrome is in the foreground. Local method so it can be overridden in tests.
-     */
-    @VisibleForTesting
-    boolean isChromeInForeground() {
-        return ApplicationStatus.hasVisibleActivities();
-    }
-
-    /** Returns whether the notification client has been started, for tests. */
-    @VisibleForTesting
-    static boolean getIsClientStartedForTest() {
-        return sIsClientStarted;
-    }
-
-    /** Returns the notification client id, for tests. */
-    @VisibleForTesting
-    @Nullable static byte[] getClientIdForTest() {
-        return sClientId;
-    }
-
-    private static String getOAuth2ScopeWithType() {
-        return "oauth2:" + SyncStatusHelper.CHROME_SYNC_OAUTH2_SCOPE;
-    }
-
-    private static void setClientId(byte[] clientId) {
-        sClientId = clientId;
-    }
-
-    private static void setIsClientStarted(boolean isStarted) {
-        sIsClientStarted = isStarted;
-    }
-}