Merge branch 'issue/2069' into 'develop'

[akkoma] / lib / pleroma / gun / connection_pool.ex

diff --git a/lib/pleroma/gun/connection_pool.ex b/lib/pleroma/gun/connection_pool.ex
index 545bfaf7fea486564d9d035914525c7575463e50..e322f192a21dc2776d685e6aa452805d985694a8 100644 (file)
--- a/lib/pleroma/gun/connection_pool.ex
+++ b/lib/pleroma/gun/connection_pool.ex
@@ -1,3 +1,7 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
 defmodule Pleroma.Gun.ConnectionPool do
   @registry __MODULE__
 
@@ -10,30 +14,29 @@ defmodule Pleroma.Gun.ConnectionPool do
     ]
   end
 
+  @spec get_conn(URI.t(), keyword()) :: {:ok, pid()} | {:error, term()}
   def get_conn(uri, opts) do
     key = "#{uri.scheme}:#{uri.host}:#{uri.port}"
 
     case Registry.lookup(@registry, key) do
       # The key has already been registered, but connection is not up yet
-      [{worker_pid, {nil, _used_by, _crf, _last_reference}}] ->
-        get_gun_pid_from_worker(worker_pid)
+      [{worker_pid, nil}] ->
+        get_gun_pid_from_worker(worker_pid, true)
 
       [{worker_pid, {gun_pid, _used_by, _crf, _last_reference}}] ->
-        GenServer.cast(worker_pid, {:add_client, self(), false})
+        GenServer.call(worker_pid, :add_client)
         {:ok, gun_pid}
 
       [] ->
         # :gun.set_owner fails in :connected state for whatevever reason,
         # so we open the connection in the process directly and send it's pid back
         # We trust gun to handle timeouts by itself
-        case WorkerSupervisor.start_worker([uri, key, opts, self()]) do
-          {:ok, _worker_pid} ->
-            receive do
-              {:conn_pid, pid} -> {:ok, pid}
-            end
+        case WorkerSupervisor.start_worker([key, uri, opts, self()]) do
+          {:ok, worker_pid} ->
+            get_gun_pid_from_worker(worker_pid, false)
 
-          {:error, {:error, {:already_registered, worker_pid}}} ->
-            get_gun_pid_from_worker(worker_pid)
+          {:error, {:already_started, worker_pid}} ->
+            get_gun_pid_from_worker(worker_pid, true)
 
           err ->
             err
@@ -41,21 +44,32 @@ defmodule Pleroma.Gun.ConnectionPool do
     end
   end
 
-  defp get_gun_pid_from_worker(worker_pid) do
+  defp get_gun_pid_from_worker(worker_pid, register) do
     # GenServer.call will block the process for timeout length if
     # the server crashes on startup (which will happen if gun fails to connect)
     # so instead we use cast + monitor
 
     ref = Process.monitor(worker_pid)
-    GenServer.cast(worker_pid, {:add_client, self(), true})
+    if register, do: GenServer.cast(worker_pid, {:add_client, self()})
 
     receive do
-      {:conn_pid, pid} -> {:ok, pid}
-      {:DOWN, ^ref, :process, ^worker_pid, reason} -> reason
+      {:conn_pid, pid} ->
+        Process.demonitor(ref)
+        {:ok, pid}
+
+      {:DOWN, ^ref, :process, ^worker_pid, reason} ->
+        case reason do
+          {:shutdown, {:error, _} = error} -> error
+          {:shutdown, error} -> {:error, error}
+          _ -> {:error, reason}
+        end
     end
   end
 
+  @spec release_conn(pid()) :: :ok
   def release_conn(conn_pid) do
+    # :ets.fun2ms(fn {_, {worker_pid, {gun_pid, _, _, _}}} when gun_pid == conn_pid ->
+    #    worker_pid end)
     query_result =
       Registry.select(@registry, [
         {{:_, :"$1", {:"$2", :_, :_, :_}}, [{:==, :"$2", conn_pid}], [:"$1"]}
@@ -63,7 +77,7 @@ defmodule Pleroma.Gun.ConnectionPool do
 
     case query_result do
       [worker_pid] ->
-        GenServer.cast(worker_pid, {:remove_client, self()})
+        GenServer.call(worker_pid, :remove_client)
 
       [] ->
         :ok