Note: Support for custom namespaces was added in version 1.3.0 of the AppSignal for Elixir package.
The AppSignal for Elixir package integrates with Plug. To set up the integration, please follow our installation guide.
This page describes how to set up AppSignal in a Plug application, and how to add instrumentation for events within requests. For more information about custom instrumentation, read the Elixir instrumentation documentation.
More information can be found in the AppSignal Hex package documentation.
We'll start out with a small Plug app that accepts
GET requests to
returns a welcome message. To start logging HTTP requests in this app, we'll
AppSignal.Plug module to the end of our app.
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defmodule AppsignalPlugExample do use Plug.Router plug :match plug :dispatch get "/" do send_resp(conn, 200, "Welcome") end use Appsignal.Plug # <-- Add this end
This will create a transaction for every HTTP request which is performed on the endpoint.
Appsignal.Plug will start transactions for you, it won't instrument
events in your app just yet. To do that, we need to add some custom
This example app looks like the one we used before, but it has a slow function
slow/0) we'd like to add instrumentation for. To do that, we need
use Appsignal.Instrumentation.Decoratorsto allow us to use AppSignal's instrumentation decorators
- Decorate the function we want to instrument with the
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defmodule AppsignalPlugExample do use Plug.Router use Appsignal.Instrumentation.Decorators # <-- 1 plug :match plug :dispatch get "/" do slow() send_resp(conn, 200, "Welcome") end @decorate transaction_event() # <-- 2 defp slow do :timer.sleep(1000) end use Appsignal.Plug end
This will add an event for the
slow/0 function to the current transaction
whenever it's called. For more information about custom instrumentation, read
the Elixir instrumentation documentation.