From bc3618a38d2e37254e27f723d3dd61679eca9be5 Mon Sep 17 00:00:00 2001
From: href <href@random.sh>
Date: Wed, 30 Jan 2019 16:32:30 +0100
Subject: [PATCH] Set up telemetry and prometheus

---
 config/config.exs           |  5 +++++
 lib/pleroma/application.ex  |  8 ++++++++
 lib/pleroma/repo.ex         |  4 ++++
 lib/pleroma/web/endpoint.ex | 20 ++++++++++++++++++++
 4 files changed, 37 insertions(+)

diff --git a/config/config.exs b/config/config.exs
index dccf7b263..1e086f44c 100644
--- a/config/config.exs
+++ b/config/config.exs
@@ -8,6 +8,10 @@ use Mix.Config
 # General application configuration
 config :pleroma, ecto_repos: [Pleroma.Repo]
 
+config :pleroma, Pleroma.Repo,
+  types: Pleroma.PostgresTypes,
+  loggers: [Pleroma.Repo.Instrumenter, Ecto.LogEntry]
+
 config :pleroma, Pleroma.Captcha,
   enabled: false,
   seconds_valid: 60,
@@ -87,6 +91,7 @@ websocket_config = [
 
 # Configures the endpoint
 config :pleroma, Pleroma.Web.Endpoint,
+  instrumenters: [Pleroma.Web.Endpoint.Instrumenter],
   url: [host: "localhost"],
   http: [
     dispatch: [
diff --git a/lib/pleroma/application.ex b/lib/pleroma/application.ex
index 782d1d589..03dcbab1a 100644
--- a/lib/pleroma/application.ex
+++ b/lib/pleroma/application.ex
@@ -25,6 +25,7 @@ defmodule Pleroma.Application do
     import Cachex.Spec
 
     Pleroma.Config.DeprecationWarnings.warn()
+    setup_instrumenters()
 
     # Define workers and child supervisors to be supervised
     children =
@@ -140,6 +141,13 @@ defmodule Pleroma.Application do
       end
   end
 
+  defp setup_instrumenters() do
+    Pleroma.Web.Endpoint.MetricsExporter.setup()
+    Pleroma.Web.Endpoint.PipelineInstrumenter.setup()
+    Pleroma.Web.Endpoint.Instrumenter.setup()
+    Pleroma.Repo.Instrumenter.setup()
+  end
+
   if Mix.env() == :test do
     defp streamer_child, do: []
     defp chat_child, do: []
diff --git a/lib/pleroma/repo.ex b/lib/pleroma/repo.ex
index 4af1bde56..aa5d427ae 100644
--- a/lib/pleroma/repo.ex
+++ b/lib/pleroma/repo.ex
@@ -8,6 +8,10 @@ defmodule Pleroma.Repo do
     adapter: Ecto.Adapters.Postgres,
     migration_timestamps: [type: :naive_datetime_usec]
 
+  defmodule Instrumenter do
+    use Prometheus.EctoInstrumenter
+  end
+
   @doc """
   Dynamically loads the repository url from the
   DATABASE_URL environment variable.
diff --git a/lib/pleroma/web/endpoint.ex b/lib/pleroma/web/endpoint.ex
index fa2d1cbe7..6d9528c86 100644
--- a/lib/pleroma/web/endpoint.ex
+++ b/lib/pleroma/web/endpoint.ex
@@ -70,6 +70,26 @@ defmodule Pleroma.Web.Endpoint do
     extra: "SameSite=Strict"
   )
 
+  # Note: the plug and its configuration is compile-time this can't be upstreamed yet
+  if proxies = Pleroma.Config.get([__MODULE__, :reverse_proxies]) do
+    plug(RemoteIp, proxies: proxies)
+  end
+
+  defmodule Instrumenter do
+    use Prometheus.PhoenixInstrumenter
+  end
+
+  defmodule PipelineInstrumenter do
+    use Prometheus.PlugPipelineInstrumenter
+  end
+
+  defmodule MetricsExporter do
+    use Prometheus.PlugExporter
+  end
+
+  plug(PipelineInstrumenter)
+  plug(MetricsExporter)
+
   plug(Pleroma.Web.Router)
 
   @doc """