迷子札 [Maigofuda]

Rails' error handling more easy!

Installation

Add this line to your application's Gemfile:

gem 'maigofuda'

And then execute:

$ bundle

Next, you need to run the generator:

$ rails generate maigofuda:install

Usage

Create extended error class from status code.

status code error class

401 Maigofuda::UnauthorizedError

422 Maigofuda::UnprocessableEntityError

ex.
```
class UserUnauthorized < Maigofuda::UnauthorizedError
end
```
Execute rake maigofuda:rebuild
Edit config/error_codes.yml and append your class' error code. ex.
```
UserUnauthorized: U12345
```

status code	error class
401	Maigofuda::UnauthorizedError
422	Maigofuda::UnprocessableEntityError

That's all.

If you raise UserUnauthorized at some action, The error is caught by Maigofuda::ErrorHandler then render json response.

{"errors":"YOUR-RAISED-MESSAGE"}

And this is accompanied by the output to the log.

<U12345> UserUnauthorized  YOUR-RAISED-MESSAGE

Customize response body

If you are not happy with the default response body, you can customize it as below:

class UserUnauthorized < Maigofuda::UnauthorizedError
  attr_accessor :special_text

  def attributes
    super.merge(special_text: special_text)
  end
end

On the other hand, if you want to customize for all errors, you can inject the class as shown below.

class YourCustomError < Maigofuda::BaseError
  attr_accessor :special_text

  def attributes
    super.mege(special_text: special_text)
  end
end

Then change config (config/initializers/maigofuda.rb) below:

Maigofuda.setup do |config|
  # ...

  config.injection_error_class = 'YourCustomError'

  # ...
end

Customize log message

You can override log message methods.

class ApplicationController < ActionController::Base

#...

  def log_prefix(error)
    "YOUR_MESSAGE_PREFIX"
  end

  def log_suffix(error)
    "YOUR_MESSAGE_SUFFIX"
  end

  def log_message(error)
    "message:#{error.message}"
  end

#...

end

<U12345> UserUnauthorized  YOUR_MESSAGE_PREFIX  message:YOUR-RAISED-MESSAGE  YOUR_MESSAGE_SUFFIX

If you hide error code or class name, you can change config (config/initializers/maigofuda.rb) below:

Maigofuda.setup do |config|

  #...

  config.print_error_code = false

  config.print_error_class = false

  #...

Hook log event

You can set hooks for log event. Inside the Hook you can access the error object using maigofuda_error.

class ApplicationController < ActionController::Base

#...

  before_maigofuda :hoge
  after_maigofuda  :fuga
  around_maigofuda :puki

  def hoge
    Rails.logger.debug 'hoge'
    Rails.logger.debug maigofuda_error.message
  end

  def fuga
    Rails.logger.debug 'fuga'
  end

  def puki
    Rails.logger.debug 'puki_before'
    yield
    Rails.logger.debug 'puki_after'
  rescue => e
    Rails.logger.debug 'puki_rescue'
    raise e
  ensure
    Rails.logger.debug 'puki_ensure'
  end

#...

Disable auto include

Maigofuda automatically includes Maigofuda::ErrorHandler and appends rescue_from to ActionController::Base and ActionController::API. If you want to disable this function, you change config and append manual include.

Maigofuda.setup do |config|

  #...

  config.auto_load = false

  #...

class HogesController < ApplicationController

  #...

  include Maigofuda::ErrorHandler

  rescue_from Maigofuda::BaseError, with: :maigofuda

  #...

License

The gem is available as open source under the terms of the MIT License.

tk-hamaguchi/maigofuda