Start adding tests for LevelDBWrapper, and fix a bunch of bugs.

In particular this fixes:
- loading data from leveldb should strip the prefix from the keys
- writing data to leveldb should preprend the prefix to the keys
- CommitChanges should actually commit changes

BUG=586194

Review-Url: https://codereview.chromium.org/2583253002
Cr-Commit-Position: refs/heads/master@{#439849}

content/browser/dom_storage/dom_storage_context_wrapper.cc

@@ -124,9 +124,6 @@ class DOMStorageContextWrapper::MojoState {
                         mojom::LevelDBObserverPtr observer,
                         mojom::LevelDBWrapperRequest request);
 
-  // Maps between an origin and its prefixed LevelDB view.
-  std::map<url::Origin, std::unique_ptr<LevelDBWrapperImpl>> level_db_wrappers_;
-
   service_manager::Connector* const connector_;
   const base::FilePath subdirectory_;
 
@@ -146,6 +143,9 @@ class DOMStorageContextWrapper::MojoState {
 
   std::vector<base::Closure> on_database_opened_callbacks_;
 
+  // Maps between an origin and its prefixed LevelDB view.
+  std::map<url::Origin, std::unique_ptr<LevelDBWrapperImpl>> level_db_wrappers_;
+
   base::WeakPtrFactory<MojoState> weak_ptr_factory_;
 };
 

content/browser/leveldb_wrapper_impl.cc

@@ -55,7 +55,7 @@ LevelDBWrapperImpl::LevelDBWrapperImpl(
     int max_bytes_per_hour,
     int max_commits_per_hour,
     const base::Closure& no_bindings_callback)
-    : prefix_(prefix),
+    : prefix_(leveldb::StdStringToUint8Vector(prefix)),
       no_bindings_callback_(no_bindings_callback),
       database_(database),
       bytes_used_(0),
@@ -249,7 +249,7 @@ void LevelDBWrapperImpl::LoadMap(const base::Closure& completion_callback) {
     return;
 
   // TODO(michaeln): Import from sqlite localstorage db.
-  database_->GetPrefixed(leveldb::StdStringToUint8Vector(prefix_),
+  database_->GetPrefixed(prefix_,
                          base::Bind(&LevelDBWrapperImpl::OnLoadComplete,
                                     weak_ptr_factory_.GetWeakPtr()));
 }
@@ -259,8 +259,11 @@ void LevelDBWrapperImpl::OnLoadComplete(
     std::vector<leveldb::mojom::KeyValuePtr> data) {
   DCHECK(!map_);
   map_.reset(new ValueMap);
-  for (auto& it : data)
-    (*map_)[it->key] = it->value;
+  for (auto& it : data) {
+    DCHECK_GE(it->key.size(), prefix_.size());
+    (*map_)[std::vector<uint8_t>(it->key.begin() + prefix_.size(),
+                                 it->key.end())] = it->value;
+  }
 
   // We proceed without using a backing store, nothing will be persisted but the
   // class is functional for the lifetime of the object.
@@ -316,7 +319,7 @@ base::TimeDelta LevelDBWrapperImpl::ComputeCommitDelay() const {
 
 void LevelDBWrapperImpl::CommitChanges() {
   DCHECK(database_);
-  if (commit_batch_)
+  if (!commit_batch_)
     return;
 
   commit_rate_limiter_.add_samples(1);
@@ -328,13 +331,15 @@ void LevelDBWrapperImpl::CommitChanges() {
     leveldb::mojom::BatchedOperationPtr item =
         leveldb::mojom::BatchedOperation::New();
     item->type = leveldb::mojom::BatchOperationType::DELETE_PREFIXED_KEY;
-    item->key = leveldb::StdStringToUint8Vector(prefix_);
+    item->key = prefix_;
     operations.push_back(std::move(item));
   }
   for (auto& it : commit_batch_->changed_values) {
     leveldb::mojom::BatchedOperationPtr item =
         leveldb::mojom::BatchedOperation::New();
-    item->key = std::move(it.first);
+    item->key.reserve(prefix_.size() + it.first.size());
+    item->key.insert(item->key.end(), prefix_.begin(), prefix_.end());
+    item->key.insert(item->key.end(), it.first.begin(), it.first.end());
     if (!it.second) {
       item->type = leveldb::mojom::BatchOperationType::DELETE_KEY;
     } else {

content/browser/leveldb_wrapper_impl.h

@@ -30,7 +30,7 @@ namespace content {
 // 2) Enforces a max_size constraint.
 // 3) Informs observers when values scoped by prefix are modified.
 // 4) Throttles requests to avoid overwhelming the disk.
-class LevelDBWrapperImpl : public mojom::LevelDBWrapper {
+class CONTENT_EXPORT LevelDBWrapperImpl : public mojom::LevelDBWrapper {
  public:
   // |no_bindings_callback| will be called when this object has no more
   // bindings.
@@ -53,6 +53,8 @@ class LevelDBWrapperImpl : public mojom::LevelDBWrapper {
   static void EnableAggressiveCommitDelay();
 
  private:
+  friend class LevelDBWrapperImplTest;
+
   using ValueMap = std::map<std::vector<uint8_t>, std::vector<uint8_t>>;
   using ChangedValueMap =
       std::map<std::vector<uint8_t>, base::Optional<std::vector<uint8_t>>>;
@@ -114,7 +116,7 @@ class LevelDBWrapperImpl : public mojom::LevelDBWrapper {
   void CommitChanges();
   void OnCommitComplete(leveldb::mojom::DatabaseError error);
 
-  std::string prefix_;
+  std::vector<uint8_t> prefix_;
   mojo::BindingSet<mojom::LevelDBWrapper> bindings_;
   mojo::InterfacePtrSet<mojom::LevelDBObserver> observers_;
   base::Closure no_bindings_callback_;

content/browser/leveldb_wrapper_impl_unittest.cc

+// Copyright 2016 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.
+
+#include "content/browser/leveldb_wrapper_impl.h"
+
+#include "base/debug/stack_trace.h"
+
+#include "components/leveldb/public/cpp/util.h"
+#include "content/public/test/test_browser_thread_bundle.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+using leveldb::StdStringToUint8Vector;
+using leveldb::Uint8VectorToStdString;
+
+namespace content {
+
+namespace {
+
+const char* kTestPrefix = "abc";
+const char* kTestSource = "source";
+const size_t kTestSizeLimit = 512;
+
+leveldb::mojom::KeyValuePtr CreateKeyValue(std::vector<uint8_t> key,
+                                           std::vector<uint8_t> value) {
+  leveldb::mojom::KeyValuePtr result = leveldb::mojom::KeyValue::New();
+  result->key = std::move(key);
+  result->value = std::move(value);
+  return result;
+}
+
+base::StringPiece AsStringPiece(const std::vector<uint8_t>& data) {
+  return base::StringPiece(reinterpret_cast<const char*>(data.data()),
+                           data.size());
+}
+
+bool StartsWith(const std::vector<uint8_t>& key,
+                const std::vector<uint8_t>& prefix) {
+  return base::StartsWith(AsStringPiece(key), AsStringPiece(prefix),
+                          base::CompareCase::SENSITIVE);
+}
+
+class MockLevelDBDatabase : public leveldb::mojom::LevelDBDatabase {
+ public:
+  explicit MockLevelDBDatabase(
+      std::map<std::vector<uint8_t>, std::vector<uint8_t>>* mock_data)
+      : mock_data_(*mock_data) {}
+
+  void Put(const std::vector<uint8_t>& key,
+           const std::vector<uint8_t>& value,
+           const PutCallback& callback) override {
+    FAIL();
+  }
+
+  void Delete(const std::vector<uint8_t>& key,
+              const DeleteCallback& callback) override {
+    FAIL();
+  }
+
+  void DeletePrefixed(const std::vector<uint8_t>& key_prefix,
+                      const DeletePrefixedCallback& callback) override {
+    FAIL();
+  }
+
+  void Write(std::vector<leveldb::mojom::BatchedOperationPtr> operations,
+             const WriteCallback& callback) override {
+    for (const auto& op : operations) {
+      switch (op->type) {
+        case leveldb::mojom::BatchOperationType::PUT_KEY:
+          mock_data_[op->key] = *op->value;
+          break;
+        case leveldb::mojom::BatchOperationType::DELETE_KEY:
+          mock_data_.erase(op->key);
+          break;
+        case leveldb::mojom::BatchOperationType::DELETE_PREFIXED_KEY:
+          FAIL();
+          break;
+      }
+    }
+    callback.Run(leveldb::mojom::DatabaseError::OK);
+  }
+
+  void Get(const std::vector<uint8_t>& key,
+           const GetCallback& callback) override {
+    FAIL();
+  }
+
+  void GetPrefixed(const std::vector<uint8_t>& key_prefix,
+                   const GetPrefixedCallback& callback) override {
+    std::vector<leveldb::mojom::KeyValuePtr> data;
+    for (const auto& row : mock_data_) {
+      if (StartsWith(row.first, key_prefix)) {
+        data.push_back(CreateKeyValue(row.first, row.second));
+      }
+    }
+    callback.Run(leveldb::mojom::DatabaseError::OK, std::move(data));
+  }
+
+  void GetSnapshot(const GetSnapshotCallback& callback) override { FAIL(); }
+
+  void ReleaseSnapshot(const base::UnguessableToken& snapshot) override {
+    FAIL();
+  }
+
+  void GetFromSnapshot(const base::UnguessableToken& snapshot,
+                       const std::vector<uint8_t>& key,
+                       const GetCallback& callback) override {
+    FAIL();
+  }
+
+  void NewIterator(const NewIteratorCallback& callback) override { FAIL(); }
+
+  void NewIteratorFromSnapshot(
+      const base::UnguessableToken& snapshot,
+      const NewIteratorFromSnapshotCallback& callback) override {
+    FAIL();
+  }
+
+  void ReleaseIterator(const base::UnguessableToken& iterator) override {
+    FAIL();
+  }
+
+  void IteratorSeekToFirst(
+      const base::UnguessableToken& iterator,
+      const IteratorSeekToFirstCallback& callback) override {
+    FAIL();
+  }
+
+  void IteratorSeekToLast(const base::UnguessableToken& iterator,
+                          const IteratorSeekToLastCallback& callback) override {
+    FAIL();
+  }
+
+  void IteratorSeek(const base::UnguessableToken& iterator,
+                    const std::vector<uint8_t>& target,
+                    const IteratorSeekToLastCallback& callback) override {
+    FAIL();
+  }
+
+  void IteratorNext(const base::UnguessableToken& iterator,
+                    const IteratorNextCallback& callback) override {
+    FAIL();
+  }
+
+  void IteratorPrev(const base::UnguessableToken& iterator,
+                    const IteratorPrevCallback& callback) override {
+    FAIL();
+  }
+
+ private:
+  std::map<std::vector<uint8_t>, std::vector<uint8_t>>& mock_data_;
+};
+
+void NoOp() {}
+
+void GetCallback(bool* called,
+                 bool* success_out,
+                 std::vector<uint8_t>* value_out,
+                 bool success,
+                 const std::vector<uint8_t>& value) {
+  *called = true;
+  *success_out = success;
+  *value_out = value;
+}
+
+void GetAllCallback(bool* called,
+                    leveldb::mojom::DatabaseError* status_out,
+                    std::vector<mojom::KeyValuePtr>* data_out,
+                    leveldb::mojom::DatabaseError status,
+                    std::vector<mojom::KeyValuePtr> data) {
+  *called = true;
+  *status_out = status;
+  *data_out = std::move(data);
+}
+
+void SuccessCallback(bool* called, bool* success_out, bool success) {
+  *called = true;
+  *success_out = success;
+}
+
+void NoOpSuccess(bool success) {}
+
+}  // namespace
+
+class LevelDBWrapperImplTest : public testing::Test {
+ public:
+  LevelDBWrapperImplTest()
+      : db_(&mock_data_),
+        level_db_wrapper_(&db_,
+                          kTestPrefix,
+                          kTestSizeLimit,
+                          base::TimeDelta::FromSeconds(5),
+                          10 * 1024 * 1024 /* max_bytes_per_hour */,
+                          60 /* max_commits_per_hour */,
+                          base::Bind(&NoOp)) {
+    set_mock_data(std::string(kTestPrefix) + "def", "defdata");
+    set_mock_data(std::string(kTestPrefix) + "123", "123data");
+    set_mock_data("123", "baddata");
+  }
+
+  void set_mock_data(const std::string& key, const std::string& value) {
+    mock_data_[StdStringToUint8Vector(key)] = StdStringToUint8Vector(value);
+  }
+
+  bool has_mock_data(const std::string& key) {
+    return mock_data_.find(StdStringToUint8Vector(key)) != mock_data_.end();
+  }
+
+  std::string get_mock_data(const std::string& key) {
+    return has_mock_data(key)
+               ? Uint8VectorToStdString(mock_data_[StdStringToUint8Vector(key)])
+               : "";
+  }
+
+  mojom::LevelDBWrapper* wrapper() { return &level_db_wrapper_; }
+
+  void CommitChanges() {
+    ASSERT_TRUE(level_db_wrapper_.commit_batch_);
+    level_db_wrapper_.CommitChanges();
+  }
+
+ private:
+  TestBrowserThreadBundle thread_bundle_;
+  std::map<std::vector<uint8_t>, std::vector<uint8_t>> mock_data_;
+  MockLevelDBDatabase db_;
+  LevelDBWrapperImpl level_db_wrapper_;
+};
+
+TEST_F(LevelDBWrapperImplTest, GetLoadedFromMap) {
+  bool called = false;
+  bool success;
+  std::vector<uint8_t> result;
+  wrapper()->Get(StdStringToUint8Vector("123"),
+                 base::Bind(&GetCallback, &called, &success, &result));
+  ASSERT_TRUE(called);
+  EXPECT_TRUE(success);
+  EXPECT_EQ(StdStringToUint8Vector("123data"), result);
+
+  called = false;
+  wrapper()->Get(StdStringToUint8Vector("x"),
+                 base::Bind(&GetCallback, &called, &success, &result));
+  ASSERT_TRUE(called);
+  EXPECT_FALSE(success);
+}
+
+TEST_F(LevelDBWrapperImplTest, GetFromPutOverwrite) {
+  std::vector<uint8_t> key = StdStringToUint8Vector("123");
+  std::vector<uint8_t> value = StdStringToUint8Vector("foo");
+
+  bool called = false;
+  bool success;
+  wrapper()->Put(key, value, kTestSource,
+                 base::Bind(&SuccessCallback, &called, &success));
+  ASSERT_TRUE(called);
+  EXPECT_TRUE(success);
+
+  called = false;
+  std::vector<uint8_t> result;
+  wrapper()->Get(key, base::Bind(&GetCallback, &called, &success, &result));
+  ASSERT_TRUE(called);
+  EXPECT_TRUE(success);
+  EXPECT_EQ(value, result);
+}
+
+TEST_F(LevelDBWrapperImplTest, GetFromPutNewKey) {
+  std::vector<uint8_t> key = StdStringToUint8Vector("newkey");
+  std::vector<uint8_t> value = StdStringToUint8Vector("foo");
+
+  bool called = false;
+  bool success;
+  wrapper()->Put(key, value, kTestSource,
+                 base::Bind(&SuccessCallback, &called, &success));
+  ASSERT_TRUE(called);
+  EXPECT_TRUE(success);
+
+  called = false;
+  std::vector<uint8_t> result;
+  wrapper()->Get(key, base::Bind(&GetCallback, &called, &success, &result));
+  ASSERT_TRUE(called);
+  EXPECT_TRUE(success);
+  EXPECT_EQ(value, result);
+}
+
+TEST_F(LevelDBWrapperImplTest, GetAll) {
+  bool called = false;
+  leveldb::mojom::DatabaseError status;
+  std::vector<mojom::KeyValuePtr> data;
+  wrapper()->GetAll(kTestSource,
+                    base::Bind(&GetAllCallback, &called, &status, &data));
+  ASSERT_TRUE(called);
+  EXPECT_EQ(leveldb::mojom::DatabaseError::OK, status);
+  EXPECT_EQ(2u, data.size());
+}
+
+TEST_F(LevelDBWrapperImplTest, CommitPutToDB) {
+  std::string key1 = "123";
+  std::string value1 = "foo";
+  std::string key2 = "abc";
+  std::string value2 = "data abc";
+
+  wrapper()->Put(StdStringToUint8Vector(key1), StdStringToUint8Vector(value1),
+                 kTestSource, base::Bind(&NoOpSuccess));
+  wrapper()->Put(StdStringToUint8Vector(key2),
+                 StdStringToUint8Vector("old value"), kTestSource,
+                 base::Bind(&NoOpSuccess));
+  wrapper()->Put(StdStringToUint8Vector(key2), StdStringToUint8Vector(value2),
+                 kTestSource, base::Bind(&NoOpSuccess));
+
+  CommitChanges();
+
+  EXPECT_TRUE(has_mock_data(kTestPrefix + key1));
+  EXPECT_EQ(value1, get_mock_data(kTestPrefix + key1));
+  EXPECT_TRUE(has_mock_data(kTestPrefix + key2));
+  EXPECT_EQ(value2, get_mock_data(kTestPrefix + key2));
+}
+
+}  // namespace content

content/test/BUILD.gn

@@ -1097,6 +1097,7 @@ test("content_unittests") {
     "../browser/indexed_db/mock_indexed_db_database_callbacks.h",
     "../browser/indexed_db/mock_indexed_db_factory.cc",
     "../browser/indexed_db/mock_indexed_db_factory.h",
+    "../browser/leveldb_wrapper_impl_unittest.cc",
     "../browser/loader/async_resource_handler_unittest.cc",
     "../browser/loader/async_revalidation_driver_unittest.cc",
     "../browser/loader/async_revalidation_manager_unittest.cc",
@@ -1385,6 +1386,8 @@ test("content_unittests") {
     "//cc/ipc",
     "//cc/surfaces",
     "//components/display_compositor",
+    "//components/leveldb/public/cpp",
+    "//components/leveldb/public/interfaces",
     "//components/payments:payment_app",
     "//components/rappor:test_support",
     "//content:resources",