Adding support for creating GitHub issues with Exception Notification gem in Rails

Gemfile

gem 'octokit', ~> '4.3.0'

github_notifier.rb

# lib/exception_notifier/github_notifier.rb
require 'action_dispatch'
require 'octokit'
require 'pp'

module ExceptionNotifier
  class GithubNotifier < BaseNotifier

    class MissingController
      def method_missing(*args, &block)
      end
    end

    def initialize(options)
      super
      @default_options = options
    end

    def call(exception, options={})
      @env = options[:env]
      @exception = exception
      @kontroller = @env['action_controller.instance'] || MissingController.new

      options = options.reverse_merge(@default_options)

      @exception = { error_class: exception.class.to_s,
                     message: exception.message.inspect,
                     backtrace: exception.backtrace }
      @data = (@env && @env['exception_notifier.exception_data'] || {}).merge(options[:data] || {})

      unless @env.nil?
        @request = ActionDispatch::Request.new(@env)

        @request_items = { url: @request.original_url,
                           http_method: @request.method,
                           ip_address: @request.remote_ip,
                           parameters: @request.filtered_parameters,
                           timestamp: Time.current }

        @session = @request.session
        @environment = @request.filtered_env
      end
      issue_options = {
        login: options.delete(:login),
        password: options.delete(:password),
        repo: options.delete(:repo),
        title: compose_title(options.delete(:prefix)),
        body: compose_body
      }
      send_notice(@exception, options, nil, issue_options) do |_msg, opts|
        client = Octokit::Client.new(login: opts[:login], password: opts[:password])
        client.create_issue(opts[:repo], opts[:title], opts[:body])
      end
    end

    private

    def compose_backtrace_section
      return '' if @exception[:backtrace].empty?
      out = sub_title('Backtrace')
      out << "<pre>#{@exception[:backtrace].join("\n")}</pre>\n"
    end

    def compose_body
      body = compose_header
      if @env.nil?
        body << compose_backtrace_section
      else
        body << compose_request_section
        body << compose_session_section
        body << compose_environment_section
        body << compose_backtrace_section
      end
      body << compose_data_section
    end

    def compose_data_section
      return '' if @data.empty?
      out = sub_title('Data')
      out << "`#{PP.pp(@data, '')}`\n"
    end

    def compose_environment_section
      out = sub_title('Environment')
      max = @environment.keys.map(&:to_s).max { |a, b| a.length <=> b.length }
      @environment.keys.map(&:to_s).sort.each do |key|
        out << "* `#{"%-*s: %s" % [max.length, key, inspect_object(@environment[key])]}`\n"
      end
      out << "\n"
    end

    def compose_header
      header = @exception.class.to_s =~ /^[aeiou]/i ? 'An' : 'A'
      header << format(" %s occurred in %s#%s:\n\n",
                       @exception[:error_class],
                       @kontroller.controller_name,
                       @kontroller.action_name)
      header << "`#{@exception[:message]}\n"
      header << "#{@exception[:backtrace].first}`\n\n"
    end

    def compose_request_section
      return '' if @request_items.empty?
      out = sub_title('Request')
      out << "* URL        : `#{@request_items[:url]}`\n"
      out << "* HTTP Method: `#{@request_items[:http_method]}`\n"
      out << "* IP address : `#{@request_items[:ip_address]}`\n"
      out << "* Parameters : `#{@request_items[:parameters].inspect}`\n"
      out << "* Timestamp : `#{@request_items[:timestamp]}`\n"
      out << "* Server : `#{Socket.gethostname}`\n"
      if defined?(Rails) && Rails.respond_to?(:root)
        out << "* Rails root : `#{Rails.root}`"
      end
      out << "* Process : `#{$$}`\n"
    end

    def compose_session_section
      out = sub_title('Session')
      id = if @request.ssl?
             out << "[FILTERED]"
           else
             rack_session_id = (@request.env["rack.session.options"] and @request.env["rack.session.options"][:id])
             (@request.session['session_id'] || rack_session_id).inspect
           end
      out << format("* session id: `%s`\n", id)
      out << "* data: `#{PP.pp(@request.session.to_hash, '')}`\n"
    end

    def compose_title(prefix = '[Error]')
      subject = "#{prefix} "
      subject << "#{@kontroller.controller_name}##{@kontroller.action_name}" if @kontroller
      subject << " (#{@exception.class})"
      subject.length > 120 ? subject[0...120] + "..." : subject
    end

    def inspect_object(object)
      case object
        when Hash, Array
          object.inspect
        else
          object.to_s
      end
    end

    def sub_title(text)
      "## #{text}:\n\n"
    end
  end
end

production.rb

# config/environment/production.rb
config.middleware.use ExceptionNotification::Rack,
                      github: {
                        prefix: '[CUSTOM ISSUE TITLE PREFIX]',
                        repo: 'Owner/project',
                        login: ENV['GITHUB_LOGIN'],
                        password: ENV['GITHUB_PASSWORD']
                      }