PlugInstrumenter

A simple plug that can be used to wrap plugs with an instrumentation callback. PipelineInstrumenter can be used in a similar fashion to Plug.Builder to instrument a plug pipeline.

Goals:

• Simple
• Flexible

NOTE: PipelineInstrumenter does not work with function plugs.

Installation

The package can be installed by adding plug_instrumenter to your list of dependencies in mix.exs:

def deps do
  [
    {:plug_instrumenter, "~> 0.1.0"}
  ]
end

Usage

PlugInstrumenter

plug PlugInstrumenter, plug: MyPlug, opts: [my_opt: :somevalue]

PipelineInstrumenter

defmodule MyApp.Pipeline do
  use PipelineInstrumenter, exclude: [MyApp.Router]

  plug MyPlug, my_opt: :somevalue

  plug MyApp.Router
end

With Phoenix

defmodule MyApp.Endpoint.Plugs do
  use PipelineInstrumenter, exclude: [MyApp.Router]

  plug MyPlug, my_opt: :somevalue

  plug MyApp.Router
end

defmodule MyApp.Endpoint do
  use Phoenix.Endpoint, otp_app: :my_app

  # unless you really want to instrument the code reloader :)
  if code_reloading? do
    plug Phoenix.CodeReloader
  end

  plug MyApp.Endpoint.Plugs
end

Default Configuration

The default configuration is as follows:

config :plug_instrumenter,
  callback: {PlugInstrumenter, :default_callback},
  now: {:erlang, :monotonic_time, [:microsecond]},
  name: MyPlug

More information is available in the documentation.