Class: HTTP::Features::Instrumentation

Inherits:
HTTP::Feature show all
Defined in:
lib/http/features/instrumentation.rb

Overview

Instrument requests and responses. Expects an ActiveSupport::Notifications-compatible instrumenter. Defaults to use a namespace of 'http' which may be overridden with a :namespace param. Emits a single event like "request.{namespace}", eg "request.http". Be sure to specify the instrumenter when enabling the feature:

HTTP .use(instrumentation: ActiveSupport::Notifications.instrumenter) .get("https://example.com/")

Emits two events on every request:

  • start_request.http before the request is made, so you can log the reqest being started
  • request.http after the response is recieved, and contains start and finish so the duration of the request can be calculated.

Defined Under Namespace

Classes: NullInstrumenter

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(instrumenter: NullInstrumenter.new, namespace: "http") ⇒ Instrumentation

Returns a new instance of Instrumentation.



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# File 'lib/http/features/instrumentation.rb', line 24

def initialize(instrumenter: NullInstrumenter.new, namespace: "http")
  super()
  @instrumenter = instrumenter
  @name = "request.#{namespace}"
  @error_name = "error.#{namespace}"
end

Instance Attribute Details

#error_name ⇒ Object (readonly)

Returns the value of attribute error_name.



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# File 'lib/http/features/instrumentation.rb', line 22

def error_name
  @error_name
end

#instrumenter ⇒ Object (readonly)

Returns the value of attribute instrumenter.



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# File 'lib/http/features/instrumentation.rb', line 22

def instrumenter
  @instrumenter
end

#name ⇒ Object (readonly)

Returns the value of attribute name.



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# File 'lib/http/features/instrumentation.rb', line 22

def name
  @name
end

Instance Method Details

#on_error(request, error) ⇒ Object 



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# File 'lib/http/features/instrumentation.rb', line 44

def on_error(request, error)
  instrumenter.instrument(error_name, request: request, error: error)
end

#wrap_request(request) ⇒ Object 



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# File 'lib/http/features/instrumentation.rb', line 31

def wrap_request(request)
  # Emit a separate "start" event, so a logger can print the request
  # being run without waiting for a response
  instrumenter.instrument("start_#{name}", request: request)
  instrumenter.start(name, request: request)
  request
end

#wrap_response(response) ⇒ Object 



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# File 'lib/http/features/instrumentation.rb', line 39

def wrap_response(response)
  instrumenter.finish(name, response: response)
  response
end