Bug 1291821 - Use sync deadline to decide of batching downloader should proceed r=rnewman

MozReview-Commit-ID: IDgIj9lBt61

--HG--
extra : rebase_source : a3d1773abb50748631e28c0aa14797b17b857def

mobile/android/services/src/main/java/org/mozilla/gecko/sync/repositories/ConstrainedServer11Repository.java

@@ -24,6 +24,7 @@ public class ConstrainedServer11Repository extends Server11Repository {
 
   public ConstrainedServer11Repository(
           String collection,
+          long syncDeadline,
           String storageURL,
           AuthHeaderProvider authHeaderProvider,
           InfoCollections infoCollections,
@@ -33,6 +34,7 @@ public class ConstrainedServer11Repository extends Server11Repository {
           boolean allowMultipleBatches) throws URISyntaxException {
     super(
             collection,
+            syncDeadline,
             storageURL,
             authHeaderProvider,
             infoCollections,

mobile/android/services/src/main/java/org/mozilla/gecko/sync/repositories/Server11Repository.java

@@ -25,7 +25,7 @@ import android.support.annotation.Nullable;
 public class Server11Repository extends Repository {
   public final AuthHeaderProvider authHeaderProvider;
 
-  /* package-local */ final long syncDeadline;
+  private final long syncDeadlineMillis;
   /* package-local */ final URI collectionURI;
 
   protected final String collection;
@@ -46,6 +46,7 @@ public class Server11Repository extends Repository {
    */
   public Server11Repository(
           @NonNull String collection,
+          long syncDeadlineMillis,
           @NonNull String storageURL,
           AuthHeaderProvider authHeaderProvider,
           @NonNull InfoCollections infoCollections,
@@ -60,6 +61,7 @@ public class Server11Repository extends Repository {
       throw new IllegalArgumentException("infoCollections must not be null");
     }
     this.collection = collection;
+    this.syncDeadlineMillis = syncDeadlineMillis;
     this.collectionURI = new URI(storageURL + (storageURL.endsWith("/") ? collection : "/" + collection));
     this.authHeaderProvider = authHeaderProvider;
     this.infoCollections = infoCollections;
@@ -100,4 +102,13 @@ public class Server11Repository extends Repository {
   public boolean getAllowMultipleBatches() {
     return true;
   }
+
+  /**
+   * A point in time by which this repository's session must complete fetch and store operations.
+   * Particularly pertinent for batching downloads performed by the session (should we fetch
+   * another batch?) and buffered repositories (do we have enough time to merge what we've downloaded?).
+   */
+  public long getSyncDeadline() {
+    return syncDeadlineMillis;
+  }
 }

mobile/android/services/src/main/java/org/mozilla/gecko/sync/repositories/Server11RepositorySession.java

@@ -112,6 +112,7 @@ public class Server11RepositorySession extends RepositorySession {
     return new BatchingDownloader(
             serverRepositorySession.serverRepository.authHeaderProvider,
             Uri.parse(serverRepositorySession.serverRepository.collectionURI().toString()),
+            serverRepositorySession.serverRepository.getSyncDeadline(),
             serverRepositorySession.serverRepository.getAllowMultipleBatches(),
             serverRepositorySession);
   }

mobile/android/services/src/main/java/org/mozilla/gecko/sync/repositories/downloaders/BatchingDownloader.java

@@ -58,6 +58,7 @@ public class BatchingDownloader {
     private final RepositorySession repositorySession;
     private final DelayedWorkTracker workTracker = new DelayedWorkTracker();
     private final Uri baseCollectionUri;
+    private final long fetchDeadline;
     private final boolean allowMultipleBatches;
 
     /* package-local */ final AuthHeaderProvider authHeaderProvider;
@@ -70,12 +71,14 @@ public class BatchingDownloader {
     public BatchingDownloader(
             AuthHeaderProvider authHeaderProvider,
             Uri baseCollectionUri,
+            long fetchDeadline,
             boolean allowMultipleBatches,
             RepositorySession repositorySession) {
         this.repositorySession = repositorySession;
         this.authHeaderProvider = authHeaderProvider;
         this.baseCollectionUri = baseCollectionUri;
         this.allowMultipleBatches = allowMultipleBatches;
+        this.fetchDeadline = fetchDeadline;
     }
 
     @VisibleForTesting
@@ -217,6 +220,12 @@ public class BatchingDownloader {
             }
         });
 
+        // Should we proceed, however? Do we have enough time?
+        if (!mayProceedWithBatching(fetchDeadline)) {
+            this.abort(fetchRecordsDelegate, new Exception("Not enough time to complete next batch"));
+            return;
+        }
+
         // Create and execute new batch request.
         try {
             final SyncStorageCollectionRequest newRequest = makeSyncStorageCollectionRequest(newer,
@@ -293,6 +302,14 @@ public class BatchingDownloader {
             }
         });
     }
+
+    private static boolean mayProceedWithBatching(long deadline) {
+        // For simplicity, allow batching to proceed if there's at least a minute left for the sync.
+        // This should be enough to fetch and process records in the batch.
+        final long timeLeft = deadline - SystemClock.elapsedRealtime();
+        return timeLeft > TimeUnit.MINUTES.toMillis(1);
+    }
+
     @VisibleForTesting
     public static URI buildCollectionURI(Uri baseCollectionUri, boolean full, long newer, long limit, String sort, String ids, String offset) throws URISyntaxException {
         Uri.Builder uriBuilder = baseCollectionUri.buildUpon();

mobile/android/services/src/main/java/org/mozilla/gecko/sync/stage/AndroidBrowserBookmarksServerSyncStage.java

@@ -41,6 +41,7 @@ public class AndroidBrowserBookmarksServerSyncStage extends ServerSyncStage {
   protected Repository getRemoteRepository() throws URISyntaxException {
     return new ConstrainedServer11Repository(
             getCollection(),
+            session.getSyncDeadline(),
             session.config.storageURL(),
             session.getAuthHeaderProvider(),
             session.config.infoCollections,

mobile/android/services/src/main/java/org/mozilla/gecko/sync/stage/AndroidBrowserHistoryServerSyncStage.java

@@ -46,6 +46,7 @@ public class AndroidBrowserHistoryServerSyncStage extends ServerSyncStage {
   protected Repository getRemoteRepository() throws URISyntaxException {
     return new ConstrainedServer11Repository(
             getCollection(),
+            session.getSyncDeadline(),
             session.config.storageURL(),
             session.getAuthHeaderProvider(),
             session.config.infoCollections,

mobile/android/services/src/main/java/org/mozilla/gecko/sync/stage/ServerSyncStage.java

@@ -144,6 +144,7 @@ public abstract class ServerSyncStage extends AbstractSessionManagingSyncStage i
   protected Repository getRemoteRepository() throws URISyntaxException {
     String collection = getCollection();
     return new Server11Repository(collection,
+                                  session.getSyncDeadline(),
                                   session.config.storageURL(),
                                   session.getAuthHeaderProvider(),
                                   session.config.infoCollections,