class OpenTelemetry::Instrumentation::Sinatra::Middlewares::TracerMiddleware

Middleware to trace Sinatra requests

Public Class Methods

new(app) click to toggle source
# File lib/opentelemetry/instrumentation/sinatra/middlewares/tracer_middleware.rb, line 13
def initialize(app)
  @app = app
end

Public Instance Methods

call(env) click to toggle source
# File lib/opentelemetry/instrumentation/sinatra/middlewares/tracer_middleware.rb, line 17
def call(env)
  extracted_context = OpenTelemetry.propagation.extract(
    env,
    getter: OpenTelemetry::Context::Propagation.rack_env_getter
  )
  OpenTelemetry::Context.with_current(extracted_context) do
    tracer.in_span(
      env['PATH_INFO'],
      attributes: { 'http.method' => env['REQUEST_METHOD'],
                    'http.url' => env['PATH_INFO'] },
      kind: :server
    ) do |span|
      @app.call(env).tap { |resp| trace_response(span, env, resp) }
    end
  end
end

Private Instance Methods

trace_response(span, env, resp) click to toggle source
# File lib/opentelemetry/instrumentation/sinatra/middlewares/tracer_middleware.rb, line 40
def trace_response(span, env, resp)
  status, _headers, _response_body = resp

  span.set_attribute('http.status_code', status)
  span.set_attribute('http.route', env['sinatra.route'].split.last) if env['sinatra.route']
  span.name = env['sinatra.route'] if env['sinatra.route']
  span.status = OpenTelemetry::Trace::Status.error unless (100..399).include?(status.to_i)
end
tracer() click to toggle source
# File lib/opentelemetry/instrumentation/sinatra/middlewares/tracer_middleware.rb, line 36
def tracer
  OpenTelemetry::Instrumentation::Sinatra::Instrumentation.instance.tracer
end