class Excon::StandardInstrumentor

def self.instrument(name, params = {}, &block)
  params = params.dup
  # reduce duplication/noise of output
  params.delete(:connection)
  params.delete(:stack)
  if params.has_key?(:headers) && params[:headers].has_key?('Authorization')
    params[:headers] = params[:headers].dup
    params[:headers]['Authorization'] = REDACTED
  end
  if params.has_key?(:password)
    params[:password] = REDACTED
  end
  $stderr.puts(name)
  indent = 0
  pretty_printer = lambda do |hash|
    indent += 2
    max_key_length = hash.keys.map {|key| key.inspect.length}.max
    hash.keys.sort_by {|key| key.to_s}.each do |key|
      value = hash[key]
      $stderr.write("#{' ' * indent}#{key.inspect.ljust(max_key_length)} => ")
      case value
      when Array
        $stderr.puts("[")
        value.each do |v|
          $stderr.puts("#{' ' * indent}  #{v.inspect}")
        end
        $stderr.write("#{' ' * indent}]")
      when Hash
        $stderr.puts("{")
        pretty_printer.call(value)
        $stderr.write("#{' ' * indent}}")
      else
        $stderr.write("#{value.inspect}")
      end
      $stderr.puts
    end
    indent -= 2
  end
  pretty_printer.call(params)
  if block_given?
    yield
  end
end