Class: Grape::Middleware::Error

Inherits:
Base
  • Object
show all
Defined in:
lib/grape/middleware/error.rb

Constant Summary

Constants inherited from Base

Base::TEXT_HTML

Instance Attribute Summary

Attributes inherited from Base

#app, #env, #options

Instance Method Summary collapse

Methods inherited from Base

#after, #before, #call, #content_type, #content_type_for, #content_types, #mime_types, #response

Methods included from DSL::Headers

#header

Constructor Details

#initialize(app, **options) ⇒ Error

Returns a new instance of Error


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# File 'lib/grape/middleware/error.rb', line 24

def initialize(app, **options)
  super
  self.class.send(:include, @options[:helpers]) if @options[:helpers]
end

Instance Method Details

#call!(env) ⇒ Object


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# File 'lib/grape/middleware/error.rb', line 29

def call!(env)
  @env = env

  begin
    error_response(catch(:error) do
      return @app.call(@env)
    end)
  rescue StandardError => e
    is_rescuable = rescuable?(e.class)
    if e.is_a?(Grape::Exceptions::Base) && (!is_rescuable || rescuable_by_grape?(e.class))
      handler = ->(arg) { error_response(arg) }
    else
      raise unless is_rescuable
      handler = find_handler(e.class)
    end

    handler.nil? ? handle_error(e) : exec_handler(e, &handler)
  end
end

#default_optionsObject


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# File 'lib/grape/middleware/error.rb', line 6

def default_options
  {
    default_status: 500, # default status returned on error
    default_message: '',
    format: :txt,
    helpers: nil,
    formatters: {},
    error_formatters: {},
    rescue_all: false, # true to rescue all exceptions
    rescue_grape_exceptions: false,
    rescue_subclasses: true, # rescue subclasses of exceptions listed
    rescue_options: { backtrace: false }, # true to display backtrace, true to let Grape handle Grape::Exceptions
    rescue_handlers: {}, # rescue handler blocks
    base_only_rescue_handlers: {}, # rescue handler blocks rescuing only the base class
    all_rescue_handler: nil # rescue handler block to rescue from all exceptions
  }
end

#error!(message, status = options[:default_status], headers = {}, backtrace = []) ⇒ Object


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# File 'lib/grape/middleware/error.rb', line 80

def error!(message, status = options[:default_status], headers = {}, backtrace = [])
  headers = headers.reverse_merge(Grape::Http::Headers::CONTENT_TYPE => content_type)
  rack_response(format_message(message, backtrace), status, headers)
end

#error_response(error = {}) ⇒ Object

TODO: This method is deprecated. Refactor out.


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# File 'lib/grape/middleware/error.rb', line 90

def error_response(error = {})
  status = error[:status] || options[:default_status]
  message = error[:message] || options[:default_message]
  headers = { Grape::Http::Headers::CONTENT_TYPE => content_type }
  headers.merge!(error[:headers]) if error[:headers].is_a?(Hash)
  backtrace = error[:backtrace] || []
  rack_response(format_message(message, backtrace), status, headers)
end

#exec_handler(e, &handler) ⇒ Object


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# File 'lib/grape/middleware/error.rb', line 72

def exec_handler(e, &handler)
  if handler.lambda? && handler.arity.zero?
    instance_exec(&handler)
  else
    instance_exec(e, &handler)
  end
end

#find_handler(klass) ⇒ Object


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# File 'lib/grape/middleware/error.rb', line 49

def find_handler(klass)
  handler = options[:rescue_handlers].find(-> { [] }) { |error, _| klass <= error }[1]
  handler ||= options[:base_only_rescue_handlers][klass]
  handler ||= options[:all_rescue_handler]

  if handler.instance_of?(Symbol)
    raise NoMethodError, "undefined method `#{handler}'" unless respond_to?(handler)
    handler = self.class.instance_method(handler).bind(self)
  end

  handler
end

#format_message(message, backtrace) ⇒ Object


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# File 'lib/grape/middleware/error.rb', line 103

def format_message(message, backtrace)
  format = env[Grape::Env::API_FORMAT] || options[:format]
  formatter = Grape::ErrorFormatter.formatter_for(format, options)
  throw :error, status: 406, message: "The requested format '#{format}' is not supported." unless formatter
  formatter.call(message, backtrace, options, env)
end

#handle_error(e) ⇒ Object


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# File 'lib/grape/middleware/error.rb', line 85

def handle_error(e)
  error_response(message: e.message, backtrace: e.backtrace)
end

#rack_response(message, status = options[:default_status], headers = { Grape::Http::Headers::CONTENT_TYPE => content_type }) ⇒ Object


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# File 'lib/grape/middleware/error.rb', line 99

def rack_response(message, status = options[:default_status], headers = { Grape::Http::Headers::CONTENT_TYPE => content_type })
  Rack::Response.new([message], status, headers).finish
end

#rescuable?(klass) ⇒ Boolean

Returns:

  • (Boolean)

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# File 'lib/grape/middleware/error.rb', line 62

def rescuable?(klass)
  return false if klass == Grape::Exceptions::InvalidVersionHeader
  rescue_all? || rescue_class_or_its_ancestor?(klass) || rescue_with_base_only_handler?(klass)
end

#rescuable_by_grape?(klass) ⇒ Boolean

Returns:

  • (Boolean)

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# File 'lib/grape/middleware/error.rb', line 67

def rescuable_by_grape?(klass)
  return false if klass == Grape::Exceptions::InvalidVersionHeader
  options[:rescue_grape_exceptions]
end