/new-relixir

New Relic tracking for Phoenix and Plug applications.

Primary LanguageElixirMIT LicenseMIT

New Relixir Build Status

Instrument your Phoenix and Plug applications with New Relic.

New Relixir currently supports instrumenting bare-bones Plug endpoints, Phoenix controllers and Ecto repositories, to record response times of web transactions and database queries.

Usage

The following instructions show how to add instrumentation with New Relixir to a hypothetical Phoenix application named MyApp.

  1. Add new_relixir to your list of dependencies and start-up applications in mix.exs:

    # mix.exs
    
    defmodule MyApp.Mixfile do
      use Mix.Project
    
      # ...
    
      def application do
        [mod: {MyApp, []},
         applications: [:new_relixir]]
      end
    
      defp deps do
        [{:new_relixir, "~> 0.4"}]
      end
    end
  2. Add your New Relic application name and license key to config/config.exs. You may wish to use environment variables to keep production, staging, and development environments separate:

    # config/config.exs
    
    config :new_relixir,
      application_name: System.get_env("NEWRELIC_APP_NAME"),
      license_key: System.get_env("NEWRELIC_LICENSE_KEY")
  3. Add NewRelixir.Instrumenters.Phoenix to the list of instrumenters in your Endpoint configuration:

    # config/config.exs
    
    config :my_app, MyAppWeb.Endpoint,
      instrumenters: [NewRelixir.Instrumenters.Phoenix],
      # ...
  4. If your app also uses Ecto, define a module to wrap your repository's methods with New Relic instrumentation:

    # lib/my_app/repo.ex
    
    defmodule MyApp.Repo do
      use Ecto.Repo, otp_app: :my_app
    
      defmodule NewRelic do
        use NewRelixir.Plug.Repo, repo: MyApp.Repo
      end
    end

    Now MyApp.Repo.NewRelic can be used as a substitute for MyApp.Repo. It will dispatch and instrument the response time for all Repo calls.

    If you've defined custom functions on your Repo, you will need to define them on your wrapper module as well. In the wrapper module, simply call your repository's original function inside a closure that you pass to instrument_db:

    # lib/my_app/repo.ex
    
    defmodule MyApp.Repo do
      use Ecto.Repo, otp_app: :my_app
    
      def my_custom_operation(queryable, opts \\ []) do
        # ...
      end
    
      defmodule NewRelic do
        use NewRelixir.Plug.Repo, repo: MyApp.Repo
    
        def my_custom_operation(queryable, opts \\ []) do
          instrument_db(:my_custom_operation, queryable, opts, fn() ->
            MyApp.Repo.my_custom_operation(queryable, opts)
          end)
        end
      end
    end

    When using the wrapper module's my_custom_operation, the time it takes to call MyApp.Repo.my_custom_operation/2 will be recorded to New Relic.

Error Reporting

If you want to report all errors to new relic

Configure your router

# lib/my_app/router.ex

defmodule MyApp.Router do
  use MyApp, :router
  use NewRelixir.Plug.Exception

  ...
end

If you want to report caught errors

try do
  raise "oops"
catch
  kind, reason ->
    transaction =
      case NewRelixir.CurrentTransaction.get() do
        {:ok, transaction} -> transaction
        {:error, _} -> NewRelixir.CurrentTransaction.set(conn.request_path)
      end

    NewRelixir.Transaction.record_error(transaction, {kind, reason})

    # You may want to re-raise this exception
    :erlang.raise(kind, reason, System.stacktrace)
end

Upgrading from 0.3.x

  1. Remove NewRelixir.Plug.Phoenix from your Plug pipeline and all further references to that module.

  2. Add NewRelixir.Instrumenters.Phoenix to the list of instrumenters in your Endpoint configuration. See more in usage.

  3. Passing a conn to the functions of your Repo wrapper is no longer required, calls to the wrapper can now be made the same way as calls to the original Repo:

    # web/controllers/users.ex
    
    defmodule MyApp.UserController do
      use MyApp.Web, :controller
    
      def index(conn, _params) do
        # Before
        users = Repo.all(User, conn: conn)
    
        # Now
        users = Repo.all(User)
      end
    end

Copyright

Copyright © 2016 The RealReal, Inc.

Distributed under the MIT License.