NAME
Log::Any::Adapter::DERIV - standardised logging to STDERR and JSON file
SYNOPSIS
use Log::Any;
# print text log to STDERR, json format when inside docker container , colored text format when STDERR is a tty, non-colored text format when STDERR is redirected.
use Log::Any::Adapter ('DERIV');
#specify STDERR directly
use Log::Any::Adapter ('DERIV', stderr => 1)
#specify STDERR's format
use Log::Any::Adapter ('DERIV', stderr => 'json')
#specify the json log name
use Log::Any::Adapter ('DERIV', json_log_file => '/var/log/program.json.log');
DESCRIPTION
Applies some opinionated log handling rules for Log::Any.
This is extremely invasive. It does the following, affecting global state in various ways:
applies UTF-8 encoding to STDERR
writes to a
.json.log
file.overrides the default Log::Any::Proxy formatter to provide data as JSON
when stringifying, may replace some problematic objects with simplified versions
An example of the string-replacement approach would be the event loop in asynchronous code: it's likely to have many components attached to it, and dumping that would effectively end up dumping the entire tree of useful objects in the process. This is a planned future extension, not currently implemented.
Why
This is provided as a CPAN module as an example for dealing with multiple outputs and formatting. The existing Log::Any::Adapter modules tend to cover one thing, and it's not immediately obvious how to extend formatting, or send data to multiple logging mechanisms at once.
Although the module may not be directly useful, it is hoped that other teams may find parts of the code useful for their own logging requirements.
There is a public repository on Github, anyone is welcome to fork that and implement their own version or make feature/bugfix suggestions if they seem generally useful:
https://github.com/binary-com/perl-Log-Any-Adapter-DERIV
PARAMETERS
json_log_file
Specify a file name that the json format log file will be printed into. If not given, then a default file 'program_name.json.log' will be used.
STDERR
If it is true, then print logs to STDERR
If the value is json or text, then print logs with that format
If the value is just a true value other than `json` or `text`, then if it is running in a container, then the logs is `json` format. Else if STDERR is a tty will be `colored text` format. Else if will be a non-color text format.
If no any parameter, then default `stderr => 1`;
_process_data
Process the data before printing out.
Takes the following arguments as named parameters:
$self
data
The log data.
Return: processed data
_filter_stack
In some cases we don't want to print stack info. This function is used to filter out the stack info.
Takes the following arguments as named parameters:
$self
data
The log data.
Return: processed data
_collapse_future_stack
The future frames are too much and too tedious. This method will keep only one frame if there are many continuously future frames. Parameter: log data Return: log data
_linux_flock_data
Param: lock type. It can be F_WRLCK or F_UNLCK
return: A FLOCK structure
_flock
call fcntl to lock or unlock a file handle
Param:
Return : true or false
_lock
Lock a file handler with fcntl.
Param: fh - File handle
Return: true or false
_unlock
Unlock a file handler locked by fcntl
Param: fh - File handle Return: true or false
level
return the current log level name
AUTHOR
Deriv Group Services Ltd. DERIV@cpan.org
LICENSE
Copyright Deriv Group Services Ltd 2020-2021. Licensed under the same terms as Perl itself.