Awesome
StructuredLogger
A structured logger with Ruby's Logger interface.
Installation
General Ruby application
Add this line to your application's Gemfile:
gem 'structured_logger'
And then execute:
$ bundle
Or install it yourself as:
$ gem install structured_logger
Rails application
Add to Gemfile
(see previous section) and run bundle
.
Write config/initializers/structured_logger.rb
.
# Use StructuredLogger instead of Logger.
l = StructuredLogger.new("log/#{Rails.env}.log")
# If you want timestamp and PID with ActiveSupport::TaggedLogging, enable next line.
#l.formatter = ::Logger::Formatter.new
# If you want tagging support, enable next line.
#l = ActiveSupport::TaggedLogging.new(l)
Rails.logger = l
Play it!
Usage
We can write log with parameters.
t = Time.now; sleep(0.1)
l = StructuredLogger.new(STDOUT)
l.debug("processed request", started_at: t, elapsed_sec: Time.now - t, status: "ok")
#=> D, [2015-08-21T05:14:37.022621 #8310] DEBUG -- : processed request: started_at=2015-08-21 05:14:36 +0900 elapsed_sec=0.100156444 status="ok"
l.debug { ["processed request", started_at: t, elapsed_sec: Time.now - t, status: "ok"] }
#=> D, [2015-08-21T05:15:00.214480 #8416] DEBUG -- : processed request: started_at=2015-08-21 05:15:00 +0900 elapsed_sec=0.100193648 status="ok"
StructuredLogger
instance methods have Ruby's Logger
interface. So, we can replace Ruby's Logger
to StructuredLogger
.
l = Logger.new(STDOUT)
l.error("Something happend")
#=> E, [2015-08-25T06:43:18.244950 #23623] ERROR -- : Something happend
l = StructuredLogger.new(STDOUT)
l.error("Something happend")
#=> E, [2015-08-25T06:43:47.798889 #23623] ERROR -- : Something happend
Also we can use it with ActiveSupport::TaggedLogging
.
l = ActiveSupport::TaggedLogging.new(StructuredLogger.new(STDOUT))
l.tagged(:crawler) do
l.tagged(:downloading) do
l.warn("malformed file format", path: downloaded_path.to_s)
end
end
#=> [crawler] [downloading] malformed file format: path="/opt/app/tmp/1234.bin"
Development
After checking out the repo, run bin/setup
to install dependencies. Then, run rake false
to run the tests. You can also run bin/console
for an interactive prompt that will allow you to experiment.
To install this gem onto your local machine, run bundle exec rake install
. To release a new version, update the version number in version.rb
.
Contributing
Bug reports and pull requests are welcome on GitHub at https://github.com/nishidayuya/structured_logger.