3 files changed, 170 insertions, 0 deletions
diff --git a/lib/pleroma/reverse_proxy/client/hackney.ex b/lib/pleroma/reverse_proxy/client/hackney.ex
new file mode 100644
index 0000000..ca4a0c2
--- /dev/null
+++ b/lib/pleroma/reverse_proxy/client/hackney.ex
@@ -0,0 +1,54 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2022 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.ReverseProxy.Client.Hackney do
+  @behaviour Pleroma.ReverseProxy.Client
+
+  # redirect handler from Pleb, slightly modified to work with Hackney
+  # https://declin.eu/objects/d4f38e62-5429-4614-86d1-e8fc16e6bf33
+  # seven years without upstream fix!
+  # https://github.com/benoitc/hackney/issues/273
+  @redirect_statuses [301, 302, 303, 307, 308]
+  defp get_location(headers) do
+    location =
+      Enum.find(headers, fn {header, _location} ->
+        String.downcase(header) == "location"
+      end)
+
+    elem(location, 1)
+  end
+
+  @impl true
+  def request(method, url, headers, body, opts \\ []) do
+    if opts[:follow_redirect] != false do
+      {_state, req_opts} = Access.get_and_update(opts, :follow_redirect, fn a -> {a, false} end)
+      res = :hackney.request(method, url, headers, body, req_opts)
+
+      case res do
+        {:ok, code, reply_headers, _client} when code in @redirect_statuses ->
+          :hackney.request(method, get_location(reply_headers), headers, body, req_opts)
+
+        {:ok, code, reply_headers} when code in @redirect_statuses ->
+          :hackney.request(method, get_location(reply_headers), headers, body, req_opts)
+
+        _ ->
+          res
+      end
+    else
+      :hackney.request(method, url, headers, body, opts)
+    end
+  end
+
+  @impl true
+  def stream_body(ref) do
+    case :hackney.stream_body(ref) do
+      :done -> :done
+      {:ok, data} -> {:ok, data, ref}
+      {:error, error} -> {:error, error}
+    end
+  end
+
+  @impl true
+  def close(ref), do: :hackney.close(ref)
+end
diff --git a/lib/pleroma/reverse_proxy/client/tesla.ex b/lib/pleroma/reverse_proxy/client/tesla.ex
new file mode 100644
index 0000000..4596d7a
--- /dev/null
+++ b/lib/pleroma/reverse_proxy/client/tesla.ex
@@ -0,0 +1,86 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2022 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.ReverseProxy.Client.Tesla do
+  @behaviour Pleroma.ReverseProxy.Client
+
+  alias Pleroma.Gun.ConnectionPool
+
+  @type headers() :: [{String.t(), String.t()}]
+  @type status() :: pos_integer()
+
+  @spec request(atom(), String.t(), headers(), String.t(), keyword()) ::
+          {:ok, status(), headers}
+          | {:ok, status(), headers, map()}
+          | {:error, atom() | String.t()}
+          | no_return()
+
+  @impl true
+  def request(method, url, headers, body, opts \\ []) do
+    check_adapter()
+
+    opts = Keyword.put(opts, :body_as, :chunks)
+
+    with {:ok, response} <-
+           Pleroma.HTTP.request(
+             method,
+             url,
+             body,
+             headers,
+             opts
+           ) do
+      if is_map(response.body) and method != :head do
+        {:ok, response.status, response.headers, response.body}
+      else
+        conn_pid = response.opts[:adapter][:conn]
+        ConnectionPool.release_conn(conn_pid)
+        {:ok, response.status, response.headers}
+      end
+    else
+      {:error, error} -> {:error, error}
+    end
+  end
+
+  @impl true
+  @spec stream_body(map()) ::
+          {:ok, binary(), map()} | {:error, atom() | String.t()} | :done | no_return()
+  def stream_body(%{pid: pid, fin: true}) do
+    ConnectionPool.release_conn(pid)
+    :done
+  end
+
+  def stream_body(client) do
+    case read_chunk!(client) do
+      {:fin, body} ->
+        {:ok, body, Map.put(client, :fin, true)}
+
+      {:nofin, part} ->
+        {:ok, part, client}
+
+      {:error, error} ->
+        {:error, error}
+    end
+  end
+
+  defp read_chunk!(%{pid: pid, stream: stream, opts: opts}) do
+    adapter = check_adapter()
+    adapter.read_chunk(pid, stream, opts)
+  end
+
+  @impl true
+  @spec close(map) :: :ok | no_return()
+  def close(%{pid: pid}) do
+    ConnectionPool.release_conn(pid)
+  end
+
+  defp check_adapter do
+    adapter = Application.get_env(:tesla, :adapter)
+
+    unless adapter == Tesla.Adapter.Gun do
+      raise "#{adapter} doesn't support reading body in chunks"
+    end
+
+    adapter
+  end
+end
diff --git a/lib/pleroma/reverse_proxy/client/wrapper.ex b/lib/pleroma/reverse_proxy/client/wrapper.ex
new file mode 100644
index 0000000..1ce4769
--- /dev/null
+++ b/lib/pleroma/reverse_proxy/client/wrapper.ex
@@ -0,0 +1,30 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2022 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.ReverseProxy.Client.Wrapper do
+  @moduledoc "Meta-client that calls the appropriate client from the config."
+  @behaviour Pleroma.ReverseProxy.Client
+
+  @impl true
+  def request(method, url, headers, body \\ "", opts \\ []) do
+    client().request(method, url, headers, body, opts)
+  end
+
+  @impl true
+  def stream_body(ref), do: client().stream_body(ref)
+
+  @impl true
+  def close(ref), do: client().close(ref)
+
+  defp client do
+    :tesla
+    |> Application.get_env(:adapter)
+    |> client()
+  end
+
+  defp client(Tesla.Adapter.Hackney), do: Pleroma.ReverseProxy.Client.Hackney
+  defp client(Tesla.Adapter.Gun), do: Pleroma.ReverseProxy.Client.Tesla
+  defp client({Tesla.Adapter.Finch, _}), do: Pleroma.ReverseProxy.Client.Hackney
+  defp client(_), do: Pleroma.Config.get!(Pleroma.ReverseProxy.Client)
+end