Refactor UKM interface for mojo-ification

components/ukm/ukm_recorder_impl.h

+// Copyright 2017 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.
+
+#ifndef COMPONENTS_UKM_UKM_RECORDER_IMPL_H_
+#define COMPONENTS_UKM_UKM_RECORDER_IMPL_H_
+
+#include <map>
+#include <set>
+#include <vector>
+
+#include "base/threading/thread_checker.h"
+#include "components/ukm/public/interfaces/ukm_interface.mojom.h"
+#include "components/ukm/public/ukm_recorder.h"
+
+namespace ukm {
+
+class UkmSource;
+class Report;
+
+namespace debug {
+class DebugPage;
+}
+
+class UkmRecorderImpl : public UkmRecorder {
+ public:
+  UkmRecorderImpl();
+  ~UkmRecorderImpl() override;
+
+  // Enables/disables recording control if data is allowed to be collected.
+  void EnableRecording();
+  void DisableRecording();
+
+  // Deletes stored recordings.
+  void Purge();
+
+ protected:
+  // Cache the list of whitelisted entries from the field trial parameter.
+  void StoreWhitelistedEntries();
+
+  // Writes recordings into a report proto, and clears recordings.
+  void StoreRecordingsInReport(Report* report);
+
+  const std::map<ukm::SourceId, std::unique_ptr<UkmSource>>& sources() const {
+    return sources_;
+  }
+
+  const std::vector<mojom::UkmEntryPtr>& entries() const { return entries_; }
+
+ private:
+  friend ::ukm::debug::DebugPage;
+  // UkmRecorder:
+  void UpdateSourceURL(SourceId source_id, const GURL& url) override;
+  void AddEntry(mojom::UkmEntryPtr entry) override;
+
+  // Whether recording new data is currently allowed.
+  bool recording_enabled_;
+
+  // Contains newly added sources and entries of UKM metrics which periodically
+  // get serialized and cleared by BuildAndStoreLog().
+  std::map<ukm::SourceId, std::unique_ptr<UkmSource>> sources_;
+  std::vector<mojom::UkmEntryPtr> entries_;
+
+  // Whitelisted Entry hashes, only the ones in this set will be recorded.
+  std::set<uint64_t> whitelisted_entry_hashes_;
+
+  THREAD_CHECKER(thread_checker_);
+};
+
+}  // namespace ukm
+
+#endif  // COMPONENTS_UKM_UKM_RECORDER_IMPL_H_