firebase
diff --git a/‎packages/firestore/CHANGELOG.md
+5 b/‎packages/firestore/CHANGELOG.md
+5
diff --git a/‎packages/firestore/src/core/sync_engine.ts
+1-13 b/‎packages/firestore/src/core/sync_engine.ts
+1-13
diff --git a/‎packages/firestore/src/local/indexeddb_mutation_queue.ts
+86-36 b/‎packages/firestore/src/local/indexeddb_mutation_queue.ts
+86-36
diff --git a/‎packages/firestore/src/local/indexeddb_persistence.ts
+57-32 b/‎packages/firestore/src/local/indexeddb_persistence.ts
+57-32
@@ -1,4 +1,9 @@
 # Unreleased
+- [changed] Improved how Firestore handles idle queries to reduce the cost of
+  re-listening within 30 minutes.
+- [changed] Improved offline performance with many outstanding writes.
+
+# 0.6.0
 - [fixed] Fixed an issue where queries returned fewer results than they should,
   caused by documents that were cached as deleted when they should not have
   been (firebase/firebase-ios-sdk#1548). Because some cache data is cleared,
 
@@ -50,7 +50,6 @@ import {
   MutationBatchState,
   OnlineState,
   OnlineStateSource,
-  ProtoByteString,
   TargetId
 } from './types';
 import {
@@ -88,12 +87,6 @@ class QueryView {
      * stream to identify this query.
      */
     public targetId: TargetId,
-    /**
-     * An identifier from the datastore backend that indicates the last state
-     * of the results that was received. This can be used to indicate where
-     * to continue receiving new doc changes for the query.
-     */
-    public resumeToken: ProtoByteString,
     /**
      * The view is responsible for computing the final merged truth of what
      * docs are in the query. It gets notified of local and remote changes,
@@ -274,12 +267,7 @@ export class SyncEngine implements RemoteSyncer, SharedClientStateSyncer {
             'applyChanges for new view should always return a snapshot'
           );
 
-          const data = new QueryView(
-            query,
-            queryData.targetId,
-            queryData.resumeToken,
-            view
-          );
+          const data = new QueryView(query, queryData.targetId, view);
           this.queryViewsByQuery.set(query, data);
           this.queryViewsByTarget[queryData.targetId] = data;
           return viewChange.snapshot!;
 
@@ -18,6 +18,7 @@ import { Timestamp } from '../api/timestamp';
 import { User } from '../auth/user';
 import { Query } from '../core/query';
 import { BatchId, ProtoByteString } from '../core/types';
+import { DocumentKeySet } from '../model/collections';
 import { DocumentKey } from '../model/document_key';
 import { Mutation } from '../model/mutation';
 import { BATCHID_UNKNOWN, MutationBatch } from '../model/mutation_batch';
@@ -40,8 +41,8 @@ import { LocalSerializer } from './local_serializer';
 import { MutationQueue } from './mutation_queue';
 import { PersistenceTransaction } from './persistence';
 import { PersistencePromise } from './persistence_promise';
-import { SimpleDb, SimpleDbStore } from './simple_db';
-import { DocumentKeySet } from '../model/collections';
+import { SimpleDbStore } from './simple_db';
+import { IndexedDbPersistence } from './indexeddb_persistence';
 
 /** A mutation queue for a specific user, backed by IndexedDB. */
 export class IndexedDbMutationQueue implements MutationQueue {
@@ -342,6 +343,50 @@ export class IndexedDbMutationQueue implements MutationQueue {
       .next(() => results);
   }
 
+  getAllMutationBatchesAffectingDocumentKeys(
+    transaction: PersistenceTransaction,
+    documentKeys: DocumentKeySet
+  ): PersistencePromise<MutationBatch[]> {
+    let uniqueBatchIDs = new SortedSet<BatchId>(primitiveComparator);
+
+    const promises: Array<PersistencePromise<void>> = [];
+    documentKeys.forEach(documentKey => {
+      const indexStart = DbDocumentMutation.prefixForPath(
+        this.userId,
+        documentKey.path
+      );
+      const range = IDBKeyRange.lowerBound(indexStart);
+
+      const promise = documentMutationsStore(transaction).iterate(
+        { range },
+        (indexKey, _, control) => {
+          const [userID, encodedPath, batchID] = indexKey;
+
+          // Only consider rows matching exactly the specific key of
+          // interest. Note that because we order by path first, and we
+          // order terminators before path separators, we'll encounter all
+          // the index rows for documentKey contiguously. In particular, all
+          // the rows for documentKey will occur before any rows for
+          // documents nested in a subcollection beneath documentKey so we
+          // can stop as soon as we hit any such row.
+          const path = EncodedResourcePath.decode(encodedPath);
+          if (userID !== this.userId || !documentKey.path.isEqual(path)) {
+            control.done();
+            return;
+          }
+
+          uniqueBatchIDs = uniqueBatchIDs.add(batchID);
+        }
+      );
+
+      promises.push(promise);
+    });
+
+    return PersistencePromise.waitFor(promises).next(() =>
+      this.lookupMutationBatches(transaction, uniqueBatchIDs)
+    );
+  }
+
   getAllMutationBatchesAffectingQuery(
     transaction: PersistenceTransaction,
     query: Query
@@ -393,34 +438,39 @@ export class IndexedDbMutationQueue implements MutationQueue {
         }
         uniqueBatchIDs = uniqueBatchIDs.add(batchID);
       })
-      .next(() => {
-        const results: MutationBatch[] = [];
-        const promises: Array<PersistencePromise<void>> = [];
-        // TODO(rockwood): Implement this using iterate.
-        uniqueBatchIDs.forEach(batchId => {
-          promises.push(
-            mutationsStore(transaction)
-              .get(batchId)
-              .next(mutation => {
-                if (!mutation) {
-                  fail(
-                    'Dangling document-mutation reference found, ' +
-                      'which points to ' +
-                      batchId
-                  );
-                }
-                assert(
-                  mutation.userId === this.userId,
-                  `Unexpected user '${
-                    mutation.userId
-                  }' for mutation batch ${batchId}`
-                );
-                results.push(this.serializer.fromDbMutationBatch(mutation!));
-              })
-          );
-        });
-        return PersistencePromise.waitFor(promises).next(() => results);
-      });
+      .next(() => this.lookupMutationBatches(transaction, uniqueBatchIDs));
+  }
+
+  private lookupMutationBatches(
+    transaction: PersistenceTransaction,
+    batchIDs: SortedSet<BatchId>
+  ): PersistencePromise<MutationBatch[]> {
+    const results: MutationBatch[] = [];
+    const promises: Array<PersistencePromise<void>> = [];
+    // TODO(rockwood): Implement this using iterate.
+    batchIDs.forEach(batchId => {
+      promises.push(
+        mutationsStore(transaction)
+          .get(batchId)
+          .next(mutation => {
+            if (mutation === null) {
+              fail(
+                'Dangling document-mutation reference found, ' +
+                  'which points to ' +
+                  batchId
+              );
+            }
+            assert(
+              mutation.userId === this.userId,
+              `Unexpected user '${
+                mutation.userId
+              }' for mutation batch ${batchId}`
+            );
+            results.push(this.serializer.fromDbMutationBatch(mutation!));
+          })
+      );
+    });
+    return PersistencePromise.waitFor(promises).next(() => results);
   }
 
   removeMutationBatches(
@@ -567,7 +617,7 @@ function convertStreamToken(token: ProtoByteString): string {
 function mutationsStore(
   txn: PersistenceTransaction
 ): SimpleDbStore<DbMutationBatchKey, DbMutationBatch> {
-  return SimpleDb.getStore<DbMutationBatchKey, DbMutationBatch>(
+  return IndexedDbPersistence.getStore<DbMutationBatchKey, DbMutationBatch>(
     txn,
     DbMutationBatch.store
   );
@@ -579,10 +629,10 @@ function mutationsStore(
 function documentMutationsStore(
   txn: PersistenceTransaction
 ): SimpleDbStore<DbDocumentMutationKey, DbDocumentMutation> {
-  return SimpleDb.getStore<DbDocumentMutationKey, DbDocumentMutation>(
-    txn,
-    DbDocumentMutation.store
-  );
+  return IndexedDbPersistence.getStore<
+    DbDocumentMutationKey,
+    DbDocumentMutation
+  >(txn, DbDocumentMutation.store);
 }
 
 /**
@@ -591,7 +641,7 @@ function documentMutationsStore(
 function mutationQueuesStore(
   txn: PersistenceTransaction
 ): SimpleDbStore<DbMutationQueueKey, DbMutationQueue> {
-  return SimpleDb.getStore<DbMutationQueueKey, DbMutationQueue>(
+  return IndexedDbPersistence.getStore<DbMutationQueueKey, DbMutationQueue>(
     txn,
     DbMutationQueue.store
   );
 
@@ -17,7 +17,7 @@
 import { User } from '../auth/user';
 import { DatabaseInfo } from '../core/database_info';
 import { JsonProtoSerializer } from '../remote/serializer';
-import { assert } from '../util/assert';
+import { assert, fail } from '../util/assert';
 import { Code, FirestoreError } from '../util/error';
 import * as log from '../util/log';
 
@@ -83,6 +83,12 @@ const UNSUPPORTED_PLATFORM_ERROR_MSG =
 //     firestore_zombie_<persistence_prefix>_<instance_key>
 const ZOMBIED_CLIENTS_KEY_PREFIX = 'firestore_zombie';
 
+export class IndexedDbTransaction extends PersistenceTransaction {
+  constructor(readonly simpleDbTransaction: SimpleDbTransaction) {
+    super();
+  }
+}
+
 /**
  * An IndexedDB-backed instance of Persistence. Data is stored persistently
  * across sessions.
@@ -115,6 +121,17 @@ const ZOMBIED_CLIENTS_KEY_PREFIX = 'firestore_zombie';
  * TODO(multitab): Update this comment with multi-tab changes.
  */
 export class IndexedDbPersistence implements Persistence {
+  static getStore<Key extends IDBValidKey, Value>(
+    txn: PersistenceTransaction,
+    store: string
+  ): SimpleDbStore<Key, Value> {
+    if (txn instanceof IndexedDbTransaction) {
+      return SimpleDb.getStore<Key, Value>(txn.simpleDbTransaction, store);
+    } else {
+      fail('IndexedDbPersistence must use instances of IndexedDbTransaction');
+    }
+  }
+
   /**
    * The name of the main (and currently only) IndexedDB database. this name is
    * appended to the prefix provided to the IndexedDbPersistence constructor.
@@ -470,7 +487,7 @@ export class IndexedDbPersistence implements Persistence {
     action: string,
     requirePrimaryLease: boolean,
     transactionOperation: (
-      transaction: PersistenceTransaction
+      transaction: IndexedDbTransaction
     ) => PersistencePromise<T>
   ): Promise<T> {
     // TODO(multitab): Consider removing `requirePrimaryLease` and exposing
@@ -483,39 +500,47 @@ export class IndexedDbPersistence implements Persistence {
 
     // Do all transactions as readwrite against all object stores, since we
     // are the only reader/writer.
-    return this.simpleDb.runTransaction('readwrite', ALL_STORES, txn => {
-      if (requirePrimaryLease) {
-        // While we merely verify that we have (or can acquire) the lease
-        // immediately, we wait to extend the primary lease until after
-        // executing transactionOperation(). This ensures that even if the
-        // transactionOperation takes a long time, we'll use a recent
-        // leaseTimestampMs in the extended (or newly acquired) lease.
-        return this.canActAsPrimary(txn)
-          .next(canActAsPrimary => {
-            if (!canActAsPrimary) {
-              // TODO(multitab): Handle this gracefully and transition back to
-              // secondary state.
-              log.error(
-                `Failed to obtain primary lease for action '${action}'.`
+    return this.simpleDb.runTransaction(
+      'readwrite',
+      ALL_STORES,
+      simpleDbTxn => {
+        if (requirePrimaryLease) {
+          // While we merely verify that we have (or can acquire) the lease
+          // immediately, we wait to extend the primary lease until after
+          // executing transactionOperation(). This ensures that even if the
+          // transactionOperation takes a long time, we'll use a recent
+          // leaseTimestampMs in the extended (or newly acquired) lease.
+          return this.canActAsPrimary(simpleDbTxn)
+            .next(canActAsPrimary => {
+              if (!canActAsPrimary) {
+                // TODO(multitab): Handle this gracefully and transition back to
+                // secondary state.
+                log.error(
+                  `Failed to obtain primary lease for action '${action}'.`
+                );
+                this.isPrimary = false;
+                this.queue.enqueue(() => this.primaryStateListener(false));
+                throw new FirestoreError(
+                  Code.FAILED_PRECONDITION,
+                  PRIMARY_LEASE_LOST_ERROR_MSG
+                );
+              }
+              return transactionOperation(
+                new IndexedDbTransaction(simpleDbTxn)
               );
-              this.isPrimary = false;
-              this.queue.enqueue(() => this.primaryStateListener(false));
-              throw new FirestoreError(
-                Code.FAILED_PRECONDITION,
-                PRIMARY_LEASE_LOST_ERROR_MSG
+            })
+            .next(result => {
+              return this.acquireOrExtendPrimaryLease(simpleDbTxn).next(
+                () => result
               );
-            }
-            return transactionOperation(txn);
-          })
-          .next(result => {
-            return this.acquireOrExtendPrimaryLease(txn).next(() => result);
-          });
-      } else {
-        return this.verifyAllowTabSynchronization(txn).next(() =>
-          transactionOperation(txn)
-        );
+            });
+        } else {
+          return this.verifyAllowTabSynchronization(simpleDbTxn).next(() =>
+            transactionOperation(new IndexedDbTransaction(simpleDbTxn))
+          );
+        }
       }
-    });
+    );
   }
 
   /**