Support PID as connection handle

Author: tomekowal

lib/tesla/adapter/hackney.ex

@@ -32,6 +32,11 @@ if Code.ensure_loaded?(:hackney) do
     @behaviour Tesla.Adapter
     alias Tesla.Multipart
 
+    # hackney 1.x uses references while hackney 2.x uses pids
+    # https://github.com/benoitc/hackney/blob/master/guides/MIGRATION.md#connection-handle
+    # further usage in code is the same
+    defguard is_hackney_connection_handle(handle) when is_reference(handle) or is_pid(handle)
+
     @impl Tesla.Adapter
     def call(env, opts) do
       with {:ok, status, headers, body} <- request(env, opts) do
@@ -46,7 +51,7 @@ if Code.ensure_loaded?(:hackney) do
     end
 
     defp format_body(data) when is_list(data), do: IO.iodata_to_binary(data)
-    defp format_body(data) when is_binary(data) or is_reference(data), do: data
+    defp format_body(data) when is_binary(data) or is_hackney_connection_handle(data), do: data
 
     defp request(env, opts) do
       request(
@@ -88,6 +93,8 @@ if Code.ensure_loaded?(:hackney) do
 
     defp send_stream(ref, body) do
       Enum.reduce_while(body, :ok, fn data, _ ->
+        IO.inspect(data)
+
         case :hackney.send_body(ref, data) do
           :ok -> {:cont, :ok}
           error -> {:halt, error}
@@ -99,12 +106,12 @@ if Code.ensure_loaded?(:hackney) do
     defp handle({:error, _} = error, _opts), do: error
     defp handle({:ok, status, headers}, _opts), do: {:ok, status, headers, []}
 
-    defp handle({:ok, ref}, _opts) when is_reference(ref) do
-      handle_async_response({ref, %{status: nil, headers: nil}})
+    defp handle({:ok, handle}, _opts) when is_hackney_connection_handle(handle) do
+      handle_async_response({handle, %{status: nil, headers: nil}})
     end
 
-    defp handle({:ok, status, headers, ref}, opts) when is_reference(ref) do
-      with {:ok, body} <- :hackney.body(ref, Keyword.get(opts, :max_body, :infinity)) do
+    defp handle({:ok, status, headers, handle}, opts) when is_hackney_connection_handle(handle) do
+      with {:ok, body} <- :hackney.body(handle, Keyword.get(opts, :max_body, :infinity)) do
         {:ok, status, headers, body}
       end
     end

test/tesla/adapter/hackney_test.exs

@@ -33,7 +33,7 @@ defmodule Tesla.Adapter.HackneyTest do
 
     assert {:ok, %Env{} = response} = call(request, with_body: true, async: true)
     assert response.status == 200
-    assert is_reference(response.body) == true
+    assert is_reference(response.body) or is_pid(response.body) == true
   end
 
   test "get with `:max_body` option" do