SYNOPSIS use Log::ger::Layout JSON => ( add_fields => {key3 => 'value', key4 => 'value', ...}, # optional add_special_fields => {_date => 'Date_GMT', _host => 'Hostname', ...}, # optional delete_fields => ['key1', 'key2', qr/some-regex/, ...], # optional ); use Log::ger; # if you use it together with Log::ger::Format::None: log_warn({key1 => 'val1', key2 => 'val2', foo => 'bar', ...); # otherwise, using the standard formatter: log_warn("blah %s", ['some', 'data']); The final message will be something like: --- foo: bar key3: value key4: value _date: "2017-06-28T14:08:22" _host: example.com or: --- message: "blah [\"some\",\"data\"]" _date: "2017-06-28T14:08:22" _host: example.com DESCRIPTION This layouter allows you to log as YAML. If you use Log::ger::Format::None, you can pass a hashref. Otherwise, the message will be put in message key. You can then delete keys then add additional fields/keys (including special fields, a la Log::ger::Layout::Pattern). CONFIGURATION add_fields => hash add_special_fields => hash Known special fields: Category: Category of the logging event Class: Fully qualified package [or class] name of the caller Date_Local: Current date in ISO8601 format (YYYY-MM-DDhh:mm:ss) (localtime) Date_GMT: Current date in ISO8601 format (YYYY-MM-DDhh:mm:ss) (GMT) File: File where the logging event occurred Hostname: (if Sys::Hostname is available) Location: Fully qualified name of the calling method followed by the callers source the file name and line number between parentheses. Line: Line number within the file where the log statement was issued Message: The message to be logged Method: Method or function where the logging request was issued Level: Level ("priority") of the logging event PID: PID of the current process Elapsed_Start: Number of seconds elapsed from program start to logging event Elapsed_Last: Number of seconds elapsed from last logging event to current logging event Stack_Trace: stack trace of functions called Unknown special fields will cause the layouter to die. delete_fields SEE ALSO Log::ger Log::ger::Layout::Pattern Log::ger::Layout::LTSV