How to set log_level for the assets:precompile task? - ruby-on-rails

Question

There is a method Rake::SprocketsTask#log_level= (defined by sprockets-3.7.1/lib/rake/sprocketstask.rb) but how to call it?
Rafael França says:
To change the logger you can define your own precompile tasks and
setting logger=
Rake::SprocketsTask.new do |t|
t.logger = Logger.new("log/assets.log")
end
I tried that (with log_level) and it returns a SprocketsTask instance, but how do I replace the assets:precompile task?
I want to set the log_level of the assets:precompile task to something quieter, like :warn.

Answer 1

some feedback, logger is an attribute of the class SprocketsTask.
require 'logger'
module Rake
# Simple Sprockets compilation Rake task macro.
#
# Rake::SprocketsTask.new do |t|
# t.environment = Sprockets::Environment.new
# t.output = "./public/assets"
# t.assets = %w( application.js application.css )
# end
#
class SprocketsTask < Rake::TaskLib
# Logger to use during rake tasks. Defaults to using stderr.
#
# t.logger = Logger.new($stdout)
#
attr_accessor :logger
I did not find the info in the api, there is some good explanation in the Rails Guide about the Log4r logger used by rails.
This is the explanation of the code you included
Rails makes use of the ActiveSupport::Logger class to write log information. Other loggers, such as Log4r, may also be substituted.
You can specify an alternative logger in config/application.rb or any other environment file, for example:
config.logger = Logger.new(STDOUT)
config.logger = Log4r::Logger.new("Application Log")
That command creates a log file by default under Rails.root/log/
The info you need are about log levels
When something is logged, it's printed into the corresponding log if the log level of the message is equal to or higher than the configured log level. If you want to know the current log level, you can call the Rails.logger.level method.
The available log levels are: :debug, :info, :warn, :error, :fatal, and :unknown, corresponding to the log level numbers from 0 up to 5, respectively. To change the default log level, use
config.log_level = :warn # In any environment initializer, or
Rails.logger.level = 0 # at any time
This is the Log4r::Logger.rb class.
It has attr_reader for :level, which is set with the def initizialize.
module Log4r
# See log4r/logger.rb
class Logger
attr_reader :name, :fullname, :path, :level, :parent
attr_reader :additive, :trace, :outputters
# Logger requires a name. The last 3 parameters are:
#
# level:: Do I have a level? (Otherwise, I'll inherit my parent's)
# additive:: Am I additive?
# trace:: Do I record the execution trace? (slows things a wee bit)
def initialize(_fullname, _level=nil, _additive=true, _trace=false)
# validation
raise ArgumentError, "Logger must have a name", caller if _fullname.nil?
Log4rTools.validate_level(_level) unless _level.nil?
validate_name(_fullname)
# create the logger
#fullname = _fullname
#outputters = []
#additive = _additive
deal_with_inheritance(_level)
LoggerFactory.define_methods(self)
self.trace = _trace
Repository[#fullname] = self
end
You can set the level by doing:
Log4r::Logger.new('Assets Log', :warn)
So I believe t.logger.level = 2 should set the level to :warn
Rake::SprocketsTask.new do |t|
t.logger = Logger.new("log/assets.log")
t.logger.level = 2
end
:debug, :info, :warn, :error, :fatal, and :unknown, corresponding to the log level numbers from 0 up to 5, respectively.
Also this works because, Log4r::Logger has a method def level=(_level) to re-set the level attribute.
# Set the logger level dynamically. Does not affect children.
def level=(_level)
Log4rTools.validate_level(_level)
#level = _level
LoggerFactory.define_methods(self)
Logger.log_internal {"Logger '#{#fullname}' set to #{LNAMES[#level]}"}
#level
end