| // 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_METRICS_METRICS_LOG_STORE_H_ |
| #define COMPONENTS_METRICS_METRICS_LOG_STORE_H_ |
| |
| #include <memory> |
| #include <string> |
| |
| #include "base/metrics/histogram_base.h" |
| #include "components/metrics/log_store.h" |
| #include "components/metrics/metrics_log.h" |
| #include "components/metrics/unsent_log_store.h" |
| #include "third_party/abseil-cpp/absl/types/optional.h" |
| |
| class PrefService; |
| class PrefRegistrySimple; |
| |
| namespace metrics { |
| |
| class MetricsServiceClient; |
| |
| // A LogStore implementation for storing UMA logs. |
| // This implementation keeps track of two types of logs, initial and ongoing, |
| // each stored in UnsentLogStore. It prioritizes staging initial logs over |
| // ongoing logs. |
| // |
| // An alternate log store can be set to persist ongoing logs. For example, this |
| // can be used to separate user logs from device logs on Chrome OS. If set, all |
| // ongoing logs will be written to this alternate log store. Ongoing logs from |
| // the alternate log store will be prioritized over ongoing logs from the native |
| // ongoing log store when logs are staged. If an alternate log store is bound, |
| // then logs will be prioritized in the following order: initial, alternate |
| // ongoing, native ongoing. |
| class MetricsLogStore : public LogStore { |
| public: |
| // Configurable limits for ensuring and restricting local log storage. |
| // |
| // |min_{initial,ongoing}_log_queue_count| are the minimum numbers of unsent |
| // logs that UnsentLogStore must persist before deleting old logs. |
| // |
| // |min_{initial,ongoing}_log_queue_size| are the minimum numbers of bytes in |
| // total across all logs within the initial or ongoing log queue that |
| // UnsentLogStore must persist before deleting old logs. |
| // |
| // If both |min_..._log_queue_count| and |min_..._log_queue_size| are 0, then |
| // this LogStore won't persist unsent logs to local storage. |
| // |
| // |max_ongoing_log_size| is the maximum size of any individual ongoing log. |
| // When set to 0, no limits are imposed, i.e. individual logs can be any size. |
| struct StorageLimits { |
| size_t min_initial_log_queue_count = 0; |
| size_t min_initial_log_queue_size = 0; |
| size_t min_ongoing_log_queue_count = 0; |
| size_t min_ongoing_log_queue_size = 0; |
| size_t max_ongoing_log_size = 0; |
| }; |
| |
| // Constructs a MetricsLogStore that persists data into |local_state|. |
| // |storage_limits| provides log count and size limits to enforce when |
| // persisting logs to local storage. |signing_key| is used to generate a |
| // signature of a log, which will be uploaded to validate data integrity. |
| MetricsLogStore(PrefService* local_state, |
| StorageLimits storage_limits, |
| const std::string& signing_key); |
| |
| MetricsLogStore(const MetricsLogStore&) = delete; |
| MetricsLogStore& operator=(const MetricsLogStore&) = delete; |
| |
| ~MetricsLogStore() override; |
| |
| // Registers local state prefs used by this class. |
| static void RegisterPrefs(PrefRegistrySimple* registry); |
| |
| // Saves |log_data| as the given type. |
| void StoreLog(const std::string& log_data, |
| MetricsLog::LogType log_type, |
| const LogMetadata& log_metadata); |
| |
| // Binds an alternate log store to be managed by |this|. All ongoing logs |
| // after this call will be written to |log_store| until it is unset. Only one |
| // alternate log store can be bound at a time. Returns true if log store is |
| // bound successfully. |
| // |
| // If an alternate log store is already bound, this function will not bind |
| // |log_store| and return false. |
| // |
| // This should be called after |LoadPersistedUnsentLogs()| and after |
| // initialization. |
| void SetAlternateOngoingLogStore(std::unique_ptr<UnsentLogStore> log_store); |
| |
| // Unsets the alternate log store by flushing all existing logs to persistent |
| // storage before destructing the alternate log store. |
| // |
| // If no alternate log store is bound, then this function no-ops. |
| void UnsetAlternateOngoingLogStore(); |
| |
| // LogStore: |
| bool has_unsent_logs() const override; |
| bool has_staged_log() const override; |
| const std::string& staged_log() const override; |
| const std::string& staged_log_hash() const override; |
| const std::string& staged_log_signature() const override; |
| absl::optional<uint64_t> staged_log_user_id() const override; |
| void StageNextLog() override; |
| void DiscardStagedLog() override; |
| void MarkStagedLogAsSent() override; |
| void TrimAndPersistUnsentLogs() override; |
| void LoadPersistedUnsentLogs() override; |
| |
| // Inspection methods for tests. |
| size_t ongoing_log_count() const { return ongoing_log_queue_.size(); } |
| size_t initial_log_count() const { return initial_log_queue_.size(); } |
| |
| // Returns true if alternate log store is set. |
| bool has_alternate_ongoing_log_store() const; |
| |
| private: |
| // Returns the log queue of the staged log. |
| const UnsentLogStore* get_staged_log_queue() const; |
| |
| // Returns true if alternate log store is set and it has unsent logs. |
| bool alternate_ongoing_log_store_has_unsent_logs() const; |
| |
| // Returns true if alternate log store is set and it has a staged log. |
| bool alternate_ongoing_log_store_has_staged_log() const; |
| |
| // Tracks whether unsent logs (if any) have been loaded from the serializer. |
| bool unsent_logs_loaded_; |
| |
| // Logs stored with the INITIAL_STABILITY_LOG type that haven't been sent yet. |
| // These logs will be staged first when staging new logs. |
| UnsentLogStore initial_log_queue_; |
| // Logs stored with the ONGOING_LOG type that haven't been sent yet. |
| UnsentLogStore ongoing_log_queue_; |
| // Alternate place to store logs stored with ONGOING_LOG type that haven't |
| // been sent yet. If initialized, all logs of type ONGOING_LOG will be stored |
| // here instead of |ongoing_log_queue_|. |
| std::unique_ptr<UnsentLogStore> alternate_ongoing_log_queue_; |
| }; |
| |
| } // namespace metrics |
| |
| #endif // COMPONENTS_METRICS_METRICS_LOG_STORE_H_ |