Logging and monitoring in Ruby on Rails - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to log an info message in Rails.

Ruby on Rails

Rails.logger.[1]("User signed in successfully")

Drag options to blanks, or click blank then click option'

Adebug

Berror

Cwarn

Dinfo

Attempts:

3 left

💡 Hint

Common Mistakes

Using debug level for normal info messages

Using warn or error for non-problematic events

The info method logs informational messages, which are useful for general application events.

2fill in blank

medium

Complete the code to set the log level to show warnings and above.

Ruby on Rails

Rails.logger.level = Logger::[1]

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ADEBUG

BWARN

CINFO

DERROR

Attempts:

3 left

💡 Hint

Common Mistakes

Setting level to DEBUG logs too much information

Setting level to INFO logs less than required

Setting the log level to WARN means only warnings, errors, and fatal messages will be logged.

3fill in blank

hard

Fix the error in the code to log an error message with exception details.

Ruby on Rails

begin
  # some code
rescue => e
  Rails.logger.[1]("Error occurred: #{e.message}")
end

Drag options to blanks, or click blank then click option'

Adebug

Binfo

Cerror

Dwarn

Attempts:

3 left

💡 Hint

Common Mistakes

Using info or debug for error messages

Using warn which is less severe than error

The error method is used to log error messages, especially exceptions.

4fill in blank

hard

Fill both blanks to create a custom logger that writes to a file and sets the log level to debug.

Ruby on Rails

custom_logger = Logger.new([1])
custom_logger.level = Logger::[2]

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A"log/custom.log"

BSTDOUT

CDEBUG

DINFO

Attempts:

3 left

💡 Hint

Common Mistakes

Using STDOUT instead of a file path for file logging

Setting log level to INFO instead of DEBUG

Creating a logger with a file path writes logs to that file. Setting level to DEBUG logs detailed messages.

5fill in blank

hard

Fill all three blanks to filter logs for requests with status code 500 or higher and log the path and status.

Ruby on Rails

ActiveSupport::Notifications.subscribe("process_action.action_controller") do |*args|
  name, start, finish, id, payload = args
  status = payload[[1]]
  path = payload[[2]]
  if status.to_i [3] 500
    Rails.logger.error("Error at #{path} with status #{status}")
  end
end

Drag options to blanks, or click blank then click option'

A:status

B:path

C>=

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using string keys instead of symbols for payload

Using equality (==) instead of greater-than-or-equal (>=) for status check

In Rails, the process_action.action_controller notification payload contains :status and :path keys, which can be used to monitor and log server errors (status ≥ 500).