2 * Copyright 2004-present Facebook, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
20 #include <folly/File.h>
21 #include <folly/Range.h>
22 #include <folly/experimental/logging/LogHandler.h>
30 * StandardLogHandler is a LogHandler implementation that uses a LogFormatter
31 * class to serialize the LogMessage into a string, and then gives it to a
34 * This basically is a simple glue class that helps chain together
35 * configurable LogFormatter and LogWriter objects.
37 * StandardLogHandler also supports ignoring messages less than a specific
38 * LogLevel. By default it processes all messages.
40 class StandardLogHandler : public LogHandler {
43 std::shared_ptr<LogFormatter> formatter,
44 std::shared_ptr<LogWriter> writer);
45 ~StandardLogHandler();
48 * Get the LogFormatter used by this handler.
50 const std::shared_ptr<LogFormatter>& getFormatter() const {
55 * Get the LogWriter used by this handler.
57 const std::shared_ptr<LogWriter>& getWriter() const {
62 * Get the handler's current LogLevel.
64 * Messages less than this LogLevel will be ignored. This defaults to
65 * LogLevel::NONE when the handler is constructed.
67 LogLevel getLevel() const {
68 return level_.load(std::memory_order_acquire);
72 * Set the handler's current LogLevel.
74 * Messages less than this LogLevel will be ignored.
76 void setLevel(LogLevel level) {
77 return level_.store(level, std::memory_order_release);
81 const LogMessage& message,
82 const LogCategory* handlerCategory) override;
84 void flush() override;
87 std::atomic<LogLevel> level_{LogLevel::NONE};
89 // The formatter_ and writer_ member variables are const, and cannot be
90 // modified after the StandardLogHandler is constructed. This allows them to
91 // be accessed without locking when handling a message. To change these
92 // values, create a new StandardLogHandler object and replace the old handler
93 // with the new one in the LoggerDB.
95 const std::shared_ptr<LogFormatter> formatter_;
96 const std::shared_ptr<LogWriter> writer_;