Fix webfinger not following redirections by using a custom dedicated Tesla client

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

lib/federation/web_finger/web_finger.ex

@@ -12,18 +12,12 @@ defmodule Mobilizon.Federation.WebFinger do
   alias Mobilizon.Actors.Actor
   alias Mobilizon.Federation.ActivityPub
   alias Mobilizon.Federation.WebFinger.XmlBuilder
+  alias Mobilizon.Service.HTTP.WebfingerClient
   alias Mobilizon.Web.Endpoint
   alias Mobilizon.Web.Router.Helpers, as: Routes
   require Jason
   require Logger
 
-  @http_options [
-    adapter: [
-      follow_redirect: true,
-      ssl: [{:versions, [:"tlsv1.2"]}]
-    ]
-  ]
-
   def host_meta do
     base_url = Endpoint.url()
 
@@ -120,17 +114,9 @@ defmodule Mobilizon.Federation.WebFinger do
     Logger.debug(inspect(address))
 
     with false <- is_nil(domain),
-         {:ok, %{} = response} <-
-           Tesla.get(
-             address,
-             headers: [
-               {"accept", "application/json, application/activity+json, application/jrd+json"}
-             ],
-             opts: @http_options
-           ),
-         %{status: status, body: body} when status in 200..299 <- response,
-         {:ok, doc} <- Jason.decode(body) do
-      webfinger_from_json(doc)
+         {:ok, %{body: body, status: code}} when code in 200..299 <-
+           WebfingerClient.get(address) do
+      webfinger_from_json(body)
     else
       e ->
         Logger.debug(fn -> "Couldn't finger #{actor}" end)

lib/service/http/rich_media_preview_client.ex

@@ -1,7 +1,6 @@
 defmodule Mobilizon.Service.HTTP.RichMediaPreviewClient do
   @moduledoc """
-  Tesla HTTP Basic Client
-  with JSON middleware
+  Tesla HTTP Basic Client that fetches HTML to extract metadata preview
   """
 
   use Tesla

lib/service/http/webfinger_client.ex

@@ -0,0 +1,34 @@
+defmodule Mobilizon.Service.HTTP.WebfingerClient do
+  @moduledoc """
+  Tesla HTTP Basic Client
+  with JSON middleware
+  """
+
+  use Tesla
+  alias Mobilizon.Config
+
+  @default_opts [
+    recv_timeout: 20_000
+  ]
+
+  adapter(Tesla.Adapter.Hackney, @default_opts)
+
+  @user_agent Config.instance_user_agent()
+
+  plug(Tesla.Middleware.FollowRedirects)
+
+  plug(Tesla.Middleware.Timeout, timeout: 10_000)
+
+  plug(Tesla.Middleware.Headers, [
+    {"User-Agent", @user_agent},
+    {"Accept", "application/json, application/activity+json, application/jrd+json"}
+  ])
+
+  plug(Tesla.Middleware.JSON,
+    decode_content_types: [
+      "application/jrd+json",
+      "application/json",
+      "application/activity+json"
+    ]
+  )
+end