Log::Any::Adapter::DERIV - standardised logging to STDERR and JSON file
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');
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.
.json.log
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.
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/bug fix suggestions if they seem generally useful:
https://github.com/binary-com/perl-Log-Any-Adapter-DERIV
json_log_file
Specify a file name to which you want the json formatted logs printed into. If not given, then it prints the logs to STDERR.
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 it prints the logs in `json` format. Else if STDERR is a tty, then it prints `colored text` format. Else it prints non-color text format.
If no parameters provided, then default `stderr => 1`;
Applies UTF-8 to filehandle if it is not utf-flavoured already
$object->apply_filehandle_utf8($fh);
$fh file handle
$fh
Formatting the log entry with timestamp, from which the message populated, severity and message.
If color/colour param passed it adds appropriate color code for timestamp, log level, from which this log message populated and actual message. For non-color mode, it just returns the formatted message.
$object->format_line($data, {color => $color});
$data hashref - The data with stack info like package method from which the message populated, timestamp, severity and message
$data
$opts hashref - the options color
$opts
Returns only formatted string if non-color mode. Otherwise returns formatted string with embedded ANSI color code using Term::ANSIColor
Add format and add color code using format_line and writes the log entry
format_line
$object->log_entry($data);
Process the data before printing out. Reduce the continues Future stack messages and filter the messages based on log level.
$object->_process_data($data);
$data hashref - The log data.
Returns a hashref - the processed data
Filter the stack message based on log level.
$object->_filter_stack($data);
$data hashref - Log stack data
Returns hashref - the filtered data
Go through the caller stack and if continuous Future messages then keep only one at the first.
$object->_collapse_future_stack($data);
Returns a hashref - the reduced log data
Check the filehandle opened to tty
Returns boolean
Returns true if we think we are currently running in a container.
At the moment this only looks for a .dockerenv file in the root directory; future versions may expand this to provide a more accurate check covering other container systems such as `runc`.
.dockerenv
Based on the type of lock requested, it packs into linux binary flock structure and return the string of that structure.
Linux struct flock: "s s l l i" short l_type short - Possible values: F_RDLCK(0) - read lock, F_WRLCK(1) - write lock, F_UNLCK(2) - unlock short l_whence - starting offset off_t l_start - relative offset off_t l_len - number of consecutive bytes to lock pid_t l_pid - process ID
$type integer lock type - F_WRLCK or F_UNLCK
$type
Returns a string of the linux flock structure
call fcntl to lock or unlock a file handle
$type lock type, either F_WRLCK or F_UNLCK
Returns boolean or undef
Lock a file handler with fcntl.
$fh File handle
Unlock a file handler locked by fcntl
Return the current log level name.
add context key value pair into data object
Set the log context hash
undef the log context hash
Mask sensitive data in the message and logs error in case of failure
$message string - The message to be masked
$message
Returns string - The masked message
alert, critical, debug, emergency, error, info, init, is_alert, is_critical, is_debug, is_emergency, is_error, is_info, is_notice, is_trace, is_warning, notice, trace, warning
delegate_method_to_slot
Deriv Group Services Ltd. DERIV@cpan.org
DERIV@cpan.org
Copyright Deriv Group Services Ltd 2020-2021. Licensed under the same terms as Perl itself.
To install Log::Any::Adapter::DERIV, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Log::Any::Adapter::DERIV
CPAN shell
perl -MCPAN -e shell install Log::Any::Adapter::DERIV
For more information on module installation, please visit the detailed CPAN module installation guide.