PryIn

PryIn is a performance metrics platform for your Phoenix application.

Installation

1. Sign up for a PryIn account and create a new project there.
2. Add pryin to your dependencies and applications list in mix.exs:

```elixir
def applications do
  [..., :pryin]
end
...
def deps do
  [{:pryin, "~> 0.1.0"}]
end
```

1. Add global configuration for the pryin app in config/config.exs:

```elixir
config :pryin,
  otp_app: :my_app,
  api_key: "your_secret_api_key",
  enabled: false,
  env: "dev"
```

1. Enable PryIn in the environments you want to collect metrics for. If you want to collect data for the production environment, for example, add the following to config/prod.exs:

```elixir
config :pryin,
  enabled: true,
  env: "prod"
```

Possible values for `env` are `dev`, `staging` or `prod`.

1. Add the PryIn plug to your application's endpoint (lib/my_app/endpoint.ex) just before the router plug:

```elixir
...
plug PryIn.Plug
plug MyApp.Router

```

1. Add the Ecto logger in config/config.exs:

```elixir
...
config :my_app, MyApp.Repo,
  loggers: [PryIn.EctoLogger, Ecto.LogEntry]
```

1. Add the PryIn instrumenter in config/config.exs:

```elixir
...
config :my_app, MyApp.Endpoint,
  ...,
  instrumenters: [PryIn.Instrumenter]
```

1. If you want to measure the runtime of custom code, wrap it in an instrumented function. To track how long calls to the Foobar Api take, for example, do the following:

```elixir
defmodule MyApp.SomeController do
  require MyApp.Endpoint
  ...

  def my_action(conn, params) do
    ...
    api_call_result =
      MyApp.Endpoint.instrument(:pryin, %{key: "foobar_api_call"}, fn ->
        FoobarApi.call(some_arguments)
    end)
    ...
  end

  ...
end
```

After this, Foobar Api call will be tracked under the key `foobar_api_call`.
Note that you need to `require` your endpoint before invoking the `instrument` macro.