LevelDB storage for data reduction proxy to store data usage stats.

components/data_reduction_proxy/core/browser/data_store_impl.cc

Index: components/data_reduction_proxy/core/browser/data_store_impl.cc
diff --git a/components/data_reduction_proxy/core/browser/data_store_impl.cc b/components/data_reduction_proxy/core/browser/data_store_impl.cc
new file mode 100644
index 0000000000000000000000000000000000000000..a29fcff08db1321804ec504138bed4d7b2a744bb
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+++ b/components/data_reduction_proxy/core/browser/data_store_impl.cc
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+// Copyright 2015 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 "components/data_reduction_proxy/core/browser/data_store_impl.h"
+
+#include "base/files/file_util.h"
+#include "base/logging.h"
+#include "base/memory/ref_counted.h"
+#include "base/metrics/histogram_macros.h"
+#include "components/data_reduction_proxy/proto/data_store.pb.h"
+#include "third_party/leveldatabase/env_chromium.h"
+#include "third_party/leveldatabase/src/include/leveldb/db.h"
+#include "third_party/leveldatabase/src/include/leveldb/env.h"
+#include "third_party/leveldatabase/src/include/leveldb/options.h"
+#include "third_party/leveldatabase/src/include/leveldb/status.h"
+#include "third_party/leveldatabase/src/include/leveldb/write_batch.h"
+
+namespace {
+
+const base::FilePath::CharType kDBName[] =
+    FILE_PATH_LITERAL("data_reduction_proxy_leveldb");
+
+data_reduction_proxy::DataStore::Status LevelDbToDRPStoreStatus(
+    leveldb::Status leveldb_status) {
+  if (leveldb_status.ok())
+    return data_reduction_proxy::DataStore::Status::OK;
+  else if (leveldb_status.IsNotFound())
+    return data_reduction_proxy::DataStore::Status::NOT_FOUND;
+  else if (leveldb_status.IsCorruption())
+    return data_reduction_proxy::DataStore::Status::CORRUPTED;
+  else if (leveldb_status.IsIOError())
+    return data_reduction_proxy::DataStore::Status::IO_ERROR;
+
+  return data_reduction_proxy::DataStore::Status::MISC_ERROR;
+}
+
+}  // namespace
+
+namespace data_reduction_proxy {
+
+DataStoreImpl::DataStoreImpl(const base::FilePath& profile_path)
+    : profile_path_(profile_path) {
+  sequence_checker_.DetachFromSequence();
+}
+
+DataStoreImpl::~DataStoreImpl() {
+  DCHECK(sequence_checker_.CalledOnValidSequencedThread());
+}
+
+void DataStoreImpl::InitializeOnDBThread() {
+  DCHECK(sequence_checker_.CalledOnValidSequencedThread());
+  DCHECK(!db_);
+
+  DataStore::Status status = OpenDB();
+  if (status == CORRUPTED)
+    RecreateDB();
+}
+
+DataStore::Status DataStoreImpl::Get(const std::string& key,
+                                     std::string* value) {
+  DCHECK(sequence_checker_.CalledOnValidSequencedThread());
+
+  if (db_.get() == nullptr) {
+    return MISC_ERROR;
+  }
+
+  leveldb::ReadOptions read_options;
+  read_options.verify_checksums = true;
+  leveldb::Slice slice(key);
+  leveldb::Status status = db_->Get(read_options, slice, value);
+  if (status.IsCorruption())
+    RecreateDB();
+
+  return LevelDbToDRPStoreStatus(status);
+}
+
+DataStore::Status DataStoreImpl::Put(
+    const std::map<std::string, std::string>& map) {
+  DCHECK(sequence_checker_.CalledOnValidSequencedThread());
+
+  if (db_.get() == nullptr) {
+    return MISC_ERROR;
+  }
+
+  leveldb::WriteBatch batch;
+  for (const auto& iter : map) {
+    leveldb::Slice key_slice(iter.first);
+    leveldb::Slice value_slice(iter.second);
+    batch.Put(key_slice, value_slice);
+  }
+
+  leveldb::WriteOptions write_options;
+  leveldb::Status status = db_->Write(write_options, &batch);
+  if (status.IsCorruption())
+    RecreateDB();
+
+  return LevelDbToDRPStoreStatus(status);
+}
+
+DataStore::Status DataStoreImpl::OpenDB() {
+  DCHECK(sequence_checker_.CalledOnValidSequencedThread());
+
+  leveldb::Options options;
+  options.create_if_missing = true;
+  options.paranoid_checks = true;
+  options.reuse_logs = leveldb_env::kDefaultLogReuseOptionValue;
+  std::string db_name = profile_path_.Append(kDBName).AsUTF8Unsafe();
+  leveldb::DB* dbptr = nullptr;
+  Status status =
+      LevelDbToDRPStoreStatus(leveldb::DB::Open(options, db_name, &dbptr));
+  UMA_HISTOGRAM_ENUMERATION("DataReductionProxy.LevelDBOpenStatus", status,
+                            STATUS_MAX);
+
+  if (status != OK)
+    LOG(ERROR) << "Failed to open Data Reduction Proxy DB: " << status;
+
+  db_.reset(dbptr);
+  return status;
+}
+
+void DataStoreImpl::RecreateDB() {
+  DCHECK(sequence_checker_.CalledOnValidSequencedThread());
+
+  LOG(WARNING) << "Deleting corrupt Data Reduction Proxy LevelDB";
+  db_.reset(nullptr);
+  base::DeleteFile(profile_path_.Append(kDBName), true);
+
+  OpenDB();
+}
+
+}  // namespace data_reduction_proxy