class DCMetro::Runner

Public Class Methods

new(argv, stdin = STDIN, stdout = STDOUT, stderr = STDERR, kernel = Kernel) click to toggle source

Allow everything fun to be injected from the outside while defaulting to normal implementations.

# File lib/dcmetro/runner.rb, line 6
def initialize(argv, stdin = STDIN, stdout = STDOUT, stderr = STDERR, kernel = Kernel)
  @argv, @stdin, @stdout, @stderr, @kernel = argv, stdin, stdout, stderr, kernel
end

Public Instance Methods

execute!() click to toggle source
# File lib/dcmetro/runner.rb, line 10
def execute!
  exit_code = begin
    # Thor accesses these streams directly rather than letting them be injected, so we replace them...
    $stderr = @stderr
    $stdin = @stdin
    $stdout = @stdout

    # Run our normal Thor app the way we know and love.
    DCMetro::Cli::Application.start(ARGV)

    # Thor::Base#start does not have a return value, assume success if no exception is raised.
    0
  rescue StandardError => e
    # The ruby interpreter would pipe this to STDERR and exit 1 in the case of an unhandled exception
    b = e.backtrace
    @stderr.puts("#{b.shift}: #{e.message} (#{e.class})")
    @stderr.puts(b.map{|s| "\tfrom #{s}"}.join("\n"))
    1
  rescue SystemExit => e
    e.status
  ensure
    # TODO: reset your app here, free up resources, etc.
    # Examples:
    # MyApp.logger.flush
    # MyApp.logger.close
    # MyApp.logger = nil
    #
    # MyApp.reset_singleton_instance_variables

    # ...then we put the streams back.
    $stderr = STDERR
    $stdin = STDIN
    $stdout = STDOUT
  end

  # Proxy our exit code back to the injected kernel.
  @kernel.exit(exit_code)
end