class HTTParty::Logger::LogstashFormatter

def content_length
  @content_length ||= response.respond_to?(:headers) ? response.headers['Content-Length'] : response['Content-Length']
end

def current_time
  Time.now.strftime('%Y-%m-%d %H:%M:%S %z')
end

def format(request, response)
  @request = request
  @response = response
  logger.public_send level, logstash_message
end

def http_method
  @http_method ||= request.http_method.name.split('::').last.upcase
end

def initialize(logger, level)
  @logger = logger
  @level  = level.to_sym
end

def logstash_message
  require 'json'
  {
    '@timestamp' => current_time,
    '@version' => 1,
    'content_length' => content_length || '-',
    'http_method' => http_method,
    'message' => message,
    'path' => path,
    'response_code' => response.code,
    'severity' => level,
    'tags' => [TAG_NAME],
  }.to_json
end

def message
  "[#{TAG_NAME}] #{response.code} \"#{http_method} #{path}\" #{content_length || '-'} "
end

def path
  @path ||= request.path.to_s
end