4 files changed, 56 insertions, 6 deletions
diff --git a/lib/pleroma/application.ex b/lib/pleroma/application.ex
index 782d1d589..1fc3fb728 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 =
@@ -126,6 +127,24 @@ defmodule Pleroma.Application do
     Supervisor.start_link(children, opts)
   end
 
+  defp setup_instrumenters do
+    require Prometheus.Registry
+
+    :ok =
+      :telemetry.attach(
+        "prometheus-ecto",
+        [:pleroma, :repo, :query],
+        &Pleroma.Repo.Instrumenter.handle_event/4,
+        %{}
+      )
+
+    Prometheus.Registry.register_collector(:prometheus_process_collector)
+    Pleroma.Web.Endpoint.MetricsExporter.setup()
+    Pleroma.Web.Endpoint.PipelineInstrumenter.setup()
+    Pleroma.Web.Endpoint.Instrumenter.setup()
+    Pleroma.Repo.Instrumenter.setup()
+  end
+
   def enabled_hackney_pools do
     [:media] ++
       if Application.get_env(:tesla, :adapter) == Tesla.Adapter.Hackney 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 """
diff --git a/lib/pleroma/web/mastodon_api/mastodon_api_controller.ex b/lib/pleroma/web/mastodon_api/mastodon_api_controller.ex
index 89fd7629a..bcc79b08a 100644
--- a/lib/pleroma/web/mastodon_api/mastodon_api_controller.ex
+++ b/lib/pleroma/web/mastodon_api/mastodon_api_controller.ex
@@ -1091,9 +1091,7 @@ defmodule Pleroma.Web.MastodonAPI.MastodonAPIController do
   end
 
   def index(%{assigns: %{user: user}} = conn, _params) do
-    token =
-      conn
-      |> get_session(:oauth_token)
+    token = get_session(conn, :oauth_token)
 
     if user && token do
       mastodon_emoji = mastodonized_emoji()
@@ -1194,6 +1192,7 @@ defmodule Pleroma.Web.MastodonAPI.MastodonAPIController do
       |> render("index.html", %{initial_state: initial_state, flavour: flavour})
     else
       conn
+      |> put_session(:return_to, conn.request_path)
       |> redirect(to: "/web/login")
     end
   end
@@ -1278,12 +1277,20 @@ defmodule Pleroma.Web.MastodonAPI.MastodonAPIController do
           scope: Enum.join(app.scopes, " ")
         )
 
-      conn
-      |> redirect(to: path)
+      redirect(conn, to: path)
     end
   end
 
-  defp local_mastodon_root_path(conn), do: mastodon_api_path(conn, :index, ["getting-started"])
+  defp local_mastodon_root_path(conn) do
+    case get_session(conn, :return_to) do
+      nil ->
+        mastodon_api_path(conn, :index, ["getting-started"])
+
+      return_to ->
+        delete_session(conn, :return_to)
+        return_to
+    end
+  end
 
   defp get_or_make_app do
     find_attrs = %{client_name: @local_mastodon_name, redirect_uris: "."}