Overlays integrate with mutations and queries, and migration (#9731)

Author: wu-hui

Firestore/Example/Firestore.xcodeproj/project.pbxproj

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 				5C7942B6244F4C416B11B86C /* leveldb_mutation_queue_test.cc */,
 				75860CD13AF47EB1EA39EC2F /* leveldb_opener_test.cc */,
+				D8A6D52723B1BABE1B7B8D8F /* leveldb_overlay_migration_manager_test.cc */,
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 				23EFC681986488B033C2B318 /* leveldb_opener_test.cc in Sources */,
+				076465DFEEEAA4CAF5A0595A /* leveldb_overlay_migration_manager_test.cc in Sources */,
 				F10A3E4E164A5458DFF7EDE6 /* leveldb_remote_document_cache_test.cc in Sources */,
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 				1DCA68BB2EF7A9144B35411F /* leveldb_opener_test.cc in Sources */,
+				80D8B7D6FFFEA12AF10E4E2B /* leveldb_overlay_migration_manager_test.cc in Sources */,
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 				98FE82875A899A40A98AAC22 /* leveldb_opener_test.cc in Sources */,
+				6F256C06FCBA46378EC35D72 /* leveldb_overlay_migration_manager_test.cc in Sources */,
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 				A06FBB7367CDD496887B86F8 /* leveldb_opener_test.cc in Sources */,
+				A9206FF8FF8834347E9C7DDB /* leveldb_overlay_migration_manager_test.cc in Sources */,
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 				8342277EB0553492B6668877 /* leveldb_opener_test.cc in Sources */,
+				EF4FB3034994E6386F3C78FF /* leveldb_overlay_migration_manager_test.cc in Sources */,
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 				4562CDD90F5FF0491F07C5DA /* leveldb_opener_test.cc in Sources */,
+				1A1299107EFF68DA9DAB19BD /* leveldb_overlay_migration_manager_test.cc in Sources */,
 				EE6DBFB0874A50578CE97A7F /* leveldb_remote_document_cache_test.cc in Sources */,
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 				6380CACCF96A9B26900983DC /* leveldb_target_cache_test.cc in Sources */,

Firestore/Example/Tests/Integration/API/FIRWriteBatchTests.mm

@@ -375,6 +375,7 @@ int64_t GetCurrentMemoryUsedInMb() {
   return -1;
 }
 
+#if !defined(THREAD_SANITIZER) && !defined(ADDRESS_SANITIZER)
 - (void)testReasonableMemoryUsageForLotsOfMutations {
   XCTestExpectation *expectation =
       [self expectationWithDescription:@"testReasonableMemoryUsageForLotsOfMutations"];
@@ -383,7 +384,7 @@ - (void)testReasonableMemoryUsageForLotsOfMutations {
   FIRWriteBatch *batch = [mainDoc.firestore batch];
 
   // > 500 mutations will be rejected.
-  const int maxMutations = 500;
+  const int maxMutations = 400;
   for (int i = 0; i != maxMutations; ++i) {
     FIRDocumentReference *nestedDoc = [[mainDoc collectionWithPath:@"nested"] documentWithAutoID];
     // The exact data doesn't matter; what is important is the large number of mutations.
@@ -401,19 +402,18 @@ - (void)testReasonableMemoryUsageForLotsOfMutations {
     const int64_t memoryUsedAfterCommitMb = GetCurrentMemoryUsedInMb();
     XCTAssertNotEqual(memoryUsedAfterCommitMb, -1);
 
-#if !defined(THREAD_SANITIZER) && !defined(ADDRESS_SANITIZER)
     // This by its nature cannot be a precise value. Runs on simulator seem to give an increase of
     // 10MB in debug mode pretty consistently. A regression would be on the scale of 500Mb.
     //
     // This check is disabled under the thread sanitizer because it introduces an overhead of
     // 5x-10x.
     XCTAssertLessThan(memoryUsedAfterCommitMb - memoryUsedBeforeCommitMb, 20);
-#endif
 
     [expectation fulfill];
   }];
   [self awaitExpectations];
 }
+#endif  // #if !defined(THREAD_SANITIZER) && !defined(ADDRESS_SANITIZER)
 
 @end
 

Firestore/core/src/immutable/sorted_set.h

@@ -141,6 +141,15 @@ class SortedSet : public SortedContainer {
     return map_.keys_in(start_key, end_key);
   }
 
+  template <typename MapType>
+  static SortedSet FromKeysOf(const MapType& map) {
+    SortedSet result;
+    for (const K& key : map.keys()) {
+      result = result.insert(key);
+    }
+    return result;
+  }
+
   friend bool operator==(const SortedSet& lhs, const SortedSet& rhs) {
     if (lhs.size() != rhs.size()) {
       return false;

Firestore/core/src/local/document_overlay_cache.cc

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2022 Google LLC
+ *
+ * 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.
+ */
+
+#include "Firestore/core/src/local/document_overlay_cache.h"
+
+#include <utility>
+
+#include "Firestore/core/src/immutable/sorted_set.h"
+#include "Firestore/core/src/model/document_key.h"
+#include "Firestore/core/src/model/overlay.h"
+
+namespace firebase {
+namespace firestore {
+namespace local {
+
+using model::DocumentKey;
+using model::DocumentKeySet;
+using model::Overlay;
+using model::OverlayByDocumentKeyMap;
+
+void DocumentOverlayCache::GetOverlays(OverlayByDocumentKeyMap& dest,
+                                       const DocumentKeySet& keys) const {
+  for (const DocumentKey& key : keys) {
+    absl::optional<Overlay> overlay = GetOverlay(key);
+    if (overlay.has_value()) {
+      dest[key] = std::move(overlay).value();
+    }
+  }
+}
+
+}  // namespace local
+}  // namespace firestore
+}  // namespace firebase

Firestore/core/src/local/document_overlay_cache.h

@@ -45,12 +45,6 @@ class DocumentOverlayCacheTestHelper;
  */
 class DocumentOverlayCache {
  public:
-  using OverlayByDocumentKeyMap = std::
-      unordered_map<model::DocumentKey, model::Overlay, model::DocumentKeyHash>;
-  using MutationByDocumentKeyMap = std::unordered_map<model::DocumentKey,
-                                                      model::Mutation,
-                                                      model::DocumentKeyHash>;
-
   virtual ~DocumentOverlayCache() = default;
 
   /**
@@ -61,13 +55,21 @@ class DocumentOverlayCache {
   virtual absl::optional<model::Overlay> GetOverlay(
       const model::DocumentKey& key) const = 0;
 
+  /**
+   * Gets the saved overlay mutation for the given document keys. Skips keys for
+   * which there are no overlays.
+   */
+  virtual void GetOverlays(model::OverlayByDocumentKeyMap& dest,
+                           const model::DocumentKeySet& keys) const;
+
   /**
    * Saves the given document key to mutation map to persistence as overlays.
    *
    * All overlays will have their largest batch id set to `largestBatchId`.
    */
-  virtual void SaveOverlays(int largest_batch_id,
-                            const MutationByDocumentKeyMap& overlays) = 0;
+  virtual void SaveOverlays(
+      int largest_batch_id,
+      const model::MutationByDocumentKeyMap& overlays) = 0;
 
   /** Removes the overlay whose largest-batch-id equals to the given ID. */
   virtual void RemoveOverlaysForBatchId(int batch_id) = 0;
@@ -80,7 +82,7 @@ class DocumentOverlayCache {
    *     Only overlays that contain a change past `sinceBatchId` are returned.
    * @return Mapping of each document key in the collection to its overlay.
    */
-  virtual OverlayByDocumentKeyMap GetOverlays(
+  virtual model::OverlayByDocumentKeyMap GetOverlays(
       const model::ResourcePath& collection, int since_batch_id) const = 0;
 
   /**
@@ -98,7 +100,7 @@ class DocumentOverlayCache {
    * @return Mapping of each document key in the collection group to its
    * overlay.
    */
-  virtual OverlayByDocumentKeyMap GetOverlays(
+  virtual model::OverlayByDocumentKeyMap GetOverlays(
       absl::string_view collection_group,
       int since_batch_id,
       std::size_t count) const = 0;

Firestore/core/src/local/leveldb_document_overlay_cache.cc

@@ -37,7 +37,9 @@ namespace local {
 using credentials::User;
 using model::DocumentKey;
 using model::Mutation;
+using model::MutationByDocumentKeyMap;
 using model::Overlay;
+using model::OverlayByDocumentKeyMap;
 using model::OverlayHash;
 using model::ResourcePath;
 using nanopb::Message;
@@ -83,9 +85,8 @@ void LevelDbDocumentOverlayCache::RemoveOverlaysForBatchId(int batch_id) {
       batch_id, [&](LevelDbDocumentOverlayKey&& key) { DeleteOverlay(key); });
 }
 
-DocumentOverlayCache::OverlayByDocumentKeyMap
-LevelDbDocumentOverlayCache::GetOverlays(const ResourcePath& collection,
-                                         int since_batch_id) const {
+OverlayByDocumentKeyMap LevelDbDocumentOverlayCache::GetOverlays(
+    const ResourcePath& collection, int since_batch_id) const {
   OverlayByDocumentKeyMap result;
   ForEachKeyInCollection(
       collection, since_batch_id, [&](LevelDbDocumentOverlayKey&& key) {
@@ -96,10 +97,10 @@ LevelDbDocumentOverlayCache::GetOverlays(const ResourcePath& collection,
   return result;
 }
 
-DocumentOverlayCache::OverlayByDocumentKeyMap
-LevelDbDocumentOverlayCache::GetOverlays(absl::string_view collection_group,
-                                         int since_batch_id,
-                                         std::size_t count) const {
+OverlayByDocumentKeyMap LevelDbDocumentOverlayCache::GetOverlays(
+    absl::string_view collection_group,
+    int since_batch_id,
+    std::size_t count) const {
   absl::optional<int> current_batch_id;
   OverlayByDocumentKeyMap result;
   ForEachKeyInCollectionGroup(