Saving command logger output to log file and console - php

Question

I wrote a very simple test command which has LoggerInterface injected in its constructor.
How am I suppose to change the monolog.yaml configuration to save this logger output to both log file and to output it to console?
monolog:
handlers:
main:
type: fingers_crossed
action_level: error
formatter: monolog.line.formatter
handler: terminal
excluded_http_codes: [404, 405]
buffer_size: 50 # How many messages should be saved? Prevent memory leaks
terminal:
type: stream
path: "php://stderr"
level: debug
console:
type: console
process_psr_3_messages: false
channels: [ "!event", "!doctrine" ]

Answer 1

The commands will always stderr by default (if you specify the -vvv option)
If you need to write the logs in a file only on error (with the stack error) you can use the finger_crossed handler :
handlers:
main:
# fingers_crossed allow to log only if action_level defined is reach
type: fingers_crossed
# minimum level to activate the handler
# available level (emergency|alert|critical|error|warning|notice|info|debug){1}
action_level: error
# wrapped handler's name
handler: nested
nested:
# stream allow to write log in file
type: stream
# path to the log file
path: "%kernel.logs_dir%/%project_name%_%kernel.environment%.log"
# available level (emergency|alert|critical|error|warning|notice|info|debug){1}
level: debug
If you want to filter a bit the logs shown in the stderr you can use the default config for the console :
console:
type: console
process_psr_3_messages: false
channels: ['!event', '!doctrine', '!console']
I'll allow you to have nicer console logs (and avoid too many "useless" logs such as event or doctrine which are very verbose)

Answer 2

You can use the "group" handler https://github.com/symfony/monolog-bundle/blob/master/DependencyInjection/Configuration.php#L137
Check an implementation here https://symfony.com/doc/current/logging/monolog_email.html

Answer 3

You can do this like your terminal handler does. copy the terminal handler and set the path to the file. Both handlers will be executed.
monolog:
handlers:
main:
...
terminal:
...
terminal_file:
type: stream
path: "%kernel.logs_dir%/%kernel.environment%-terminal.log"
level: debug
You can also do this to log different channels to different files.
Sometimes i use this, to log doctrine debug messages to a different file, by adding the doctrine channel.
monolog:
handlers:
...
doctrine_debug:
type: stream
path: "%kernel.logs_dir%/%kernel.environment%-doctrine.log"
level: debug
channels: ["doctrine"]