Class: Serf::Middleware::ErrorHandler

Inherits:
Object
  • Object
show all
Includes:
Util::ErrorHandling
Defined in:
lib/serf/middleware/error_handler.rb

Overview

Middleware to catch raised exceptions and return an error parcel instead.

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Util::ErrorHandling

#handle_error, #with_error_handling

Methods included from Util::ProtectedCall

#pcall

Constructor Details

#initialize(app, *args) ⇒ ErrorHandler

Returns a new instance of ErrorHandler.

Parameters:

  • app —

    the app



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# File 'lib/serf/middleware/error_handler.rb', line 23

def initialize(app, *args)
  opts = Optser.extract_options! args
  @app = app

  # Tunable knobs
  @parcel_factory = opts.get(:parcel_factory) { Serf::ParcelFactory.new }
end

Instance Attribute Details

#app ⇒ Object (readonly)

Returns the value of attribute app.



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# File 'lib/serf/middleware/error_handler.rb', line 17

def app
  @app
end

#parcel_factory ⇒ Object (readonly)

Returns the value of attribute parcel_factory.



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# File 'lib/serf/middleware/error_handler.rb', line 18

def parcel_factory
  @parcel_factory
end

Instance Method Details

#call(parcel) ⇒ Object 



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# File 'lib/serf/middleware/error_handler.rb', line 31

def call(parcel)
  # Attempt to execute the app, catching errors
  response_parcel, error_message = with_error_handling do
    app.call parcel
  end

  # Return on success
  return response_parcel if response_parcel

  # We got an error message, so build out and return the error parcel
  return parcel_factory.create(
    kind: 'serf/events/caught_error',
    parent: parcel,
    message: error_message)
end