impala::SimpleLogger Class Reference

#include <simple-logger.h>

Collaboration diagram for impala::SimpleLogger:

Public Member Functions
	SimpleLogger (const std::string &log_dir_, const std::string &log_file_name_prefix_, uint64_t max_entries_per_file)
Status	Init ()
Status	AppendEntry (const std::string &entry)
Status	Flush ()

Private Member Functions
void	GenerateLogFileName ()
Status	FlushInternal ()

Private Attributes
boost::mutex	log_file_lock_
	Protects log_file_, num_log_file_entries_ and log_file_name_. More...
std::string	log_dir_
	Directory to log to. More...
std::string	log_file_name_prefix_
	Prefix for all log files. More...
uint64_t	num_log_file_entries_
uint64_t	max_entries_per_file_
std::ofstream	log_file_
	Log files are written to this stream. More...
std::string	log_file_name_
	Current log file name. More...

Detailed Description

A class that provides basic thread-safe support for logging to a file. Supports creation of the log file and log directories as well as rolling the log file when it has reached a specified number of entries.

Definition at line 28 of file simple-logger.h.

Constructor & Destructor Documentation

SimpleLogger::SimpleLogger	(	const std::string &	log_dir_,
		const std::string &	log_file_name_prefix_,
		uint64_t	max_entries_per_file
	)

Definition at line 61 of file simple-logger.cc.

Member Function Documentation

Status SimpleLogger::AppendEntry

(

const std::string &

entry

)

Appends the given string to the log file, including a newline. If the log file already contains the specified entry limit, a new log file will be created. This function is thread safe and blocks while a Flush() is in progress

Definition at line 80 of file simple-logger.cc.

References FlushInternal(), GenerateLogFileName(), log_file_, log_file_lock_, log_file_name_, max_entries_per_file_, num_log_file_entries_, impala::Status::OK, and RETURN_IF_ERROR.

Status SimpleLogger::Flush

(

)

Flushes the log file to disk by closing and re-opening the file. This function is thread safe and blocks while a WriteEntry() is in progress

Definition at line 94 of file simple-logger.cc.

References FlushInternal(), and log_file_lock_.

Status SimpleLogger::FlushInternal ( )

private

Flushes the log file to disk (closes and reopens the file). Must be called with the log_file_lock_ held.

Definition at line 99 of file simple-logger.cc.

References log_file_, log_file_name_, and impala::Status::OK.

Referenced by AppendEntry(), Flush(), and Init().

void SimpleLogger::GenerateLogFileName ( )

private

Generates and sets a new log file name that is based off the log file name prefix and the current system time. The format will be: PREFIX-<UTC timestamp>="">

Definition at line 53 of file simple-logger.cc.

References EPOCH, log_dir_, log_file_name_, and log_file_name_prefix_.

Referenced by AppendEntry(), and Init().

Status SimpleLogger::Init

(

)

Initializes the logging directory and creates the initial log file. If the log dir does not already exist, it will be created. This function is not thread safe and should only be called once.

Definition at line 69 of file simple-logger.cc.

References FlushInternal(), GenerateLogFileName(), InitLoggingDir(), log_dir_, log_file_name_, impala::Status::OK, and RETURN_IF_ERROR.

Member Data Documentation

std::string impala::SimpleLogger::log_dir_

private

Directory to log to.

Definition at line 52 of file simple-logger.h.

Referenced by GenerateLogFileName(), and Init().

std::ofstream impala::SimpleLogger::log_file_

private

Log files are written to this stream.

Definition at line 66 of file simple-logger.h.

Referenced by AppendEntry(), and FlushInternal().

boost::mutex impala::SimpleLogger::log_file_lock_

private

Protects log_file_, num_log_file_entries_ and log_file_name_.

Definition at line 49 of file simple-logger.h.

Referenced by AppendEntry(), and Flush().

std::string impala::SimpleLogger::log_file_name_

private

Current log file name.

Definition at line 69 of file simple-logger.h.

Referenced by AppendEntry(), FlushInternal(), GenerateLogFileName(), and Init().

std::string impala::SimpleLogger::log_file_name_prefix_

private

Prefix for all log files.

Definition at line 55 of file simple-logger.h.

Referenced by GenerateLogFileName().

uint64_t impala::SimpleLogger::max_entries_per_file_

private

The maximum number of entries for each log file. If this number is reached the log file will be rolled

Definition at line 63 of file simple-logger.h.

Referenced by AppendEntry().

uint64_t impala::SimpleLogger::num_log_file_entries_

private

Counts the number of entries written to log_file_; used to decide when to roll the log file

Definition at line 59 of file simple-logger.h.

Referenced by AppendEntry().

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The documentation for this class was generated from the following files:

• be/src/util/simple-logger.h
• be/src/util/simple-logger.cc