1/* Copyright 2018 The TensorFlow Authors. All Rights Reserved.
2
3Licensed under the Apache License, Version 2.0 (the "License");
4you may not use this file except in compliance with the License.
5You may obtain a copy of the License at
6
7 http://www.apache.org/licenses/LICENSE-2.0
8
9Unless required by applicable law or agreed to in writing, software
10distributed under the License is distributed on an "AS IS" BASIS,
11WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12See the License for the specific language governing permissions and
13limitations under the License.
14==============================================================================*/
15
16#ifndef TENSORFLOW_TSL_PLATFORM_LOGGER_H_
17#define TENSORFLOW_TSL_PLATFORM_LOGGER_H_
18
19#include "google/protobuf/any.pb.h"
20#include "tensorflow/tsl/platform/protobuf.h"
21
22namespace tsl {
23
24// Abstract logging interface. Contrary to logging.h, this class describes an
25// interface, not a concrete logging mechanism. This is useful when we want to
26// log anything to a non-local place, e.g. a database.
27class Logger {
28 public:
29 // The singleton is supposed to be used in the following steps:
30 // * At program start time, REGISTER_MODULE_INITIALIZER calls
31 // SetSingletonFactory.
32 // * At some point in the program execution, Singleton() is called for the
33 // first time, initializing the logger.
34 // * Succeeding calls to Singleton() return the initialized logger.
35 using FactoryFunc = Logger* (*)();
36
37 static void SetSingletonFactory(FactoryFunc factory) {
38 singleton_factory_ = factory;
39 }
40
41 // Returns the per-process Logger instance, constructing synchronously it if
42 // necessary.
43 static Logger* GetSingleton();
44
45 // Like GetSingleton, except that this does not wait for the construction of
46 // Logger to finish before returning.
47 //
48 // Returns the constructed instance of Logger if it has been constructed,
49 // otherwise returns nullptr (if the logger is not ready yet).
50 static Logger* GetSingletonAsync();
51
52 virtual ~Logger() = default;
53
54 // Logs a typed proto.
55 template <typename ProtoType>
56 void LogProto(const ProtoType& proto) {
57 google::protobuf::Any any;
58 any.PackFrom(proto);
59 DoLogProto(&any);
60 }
61
62 // Flushes any pending log. Blocks until everything is flushed.
63 void Flush() { DoFlush(); }
64
65 private:
66 virtual void DoLogProto(google::protobuf::Any* proto) = 0;
67 virtual void DoFlush() = 0;
68
69 static FactoryFunc singleton_factory_;
70
71 friend struct AsyncSingletonImpl;
72};
73
74} // namespace tsl
75
76#endif // TENSORFLOW_TSL_PLATFORM_LOGGER_H_
77