Create tesla middleware for adding signature to federation requests

Change repo structure

lib/matrix_server_web/client/authenticate_client_plug.ex

@@ -1,5 +1,5 @@
-defmodule MatrixServerWeb.Plug.AuthenticateClient do
-  import MatrixServerWeb.Plug.Error
+defmodule MatrixServerWeb.Client.AuthenticateClientPlug do
+  import MatrixServerWeb.Error
   import Plug.Conn
 
   alias MatrixServer.Account

lib/matrix_server_web/client/controllers/account_controller.ex

@@ -2,7 +2,7 @@ defmodule MatrixServerWeb.Client.AccountController do
   use MatrixServerWeb, :controller
 
   import MatrixServer
-  import MatrixServerWeb.Plug.Error
+  import MatrixServerWeb.Error
 
   alias MatrixServer.{Account, Repo}
   alias Plug.Conn

lib/matrix_server_web/client/controllers/aliases_controller.ex

@@ -1,7 +1,7 @@
 defmodule MatrixServerWeb.Client.AliasesController do
   use MatrixServerWeb, :controller
 
-  import MatrixServerWeb.Plug.Error
+  import MatrixServerWeb.Error
 
   alias MatrixServer.Alias
 

lib/matrix_server_web/client/controllers/info_controller.ex

@@ -1,7 +1,7 @@
 defmodule MatrixServerWeb.Client.InfoController do
   use MatrixServerWeb, :controller
 
-  import MatrixServerWeb.Plug.Error
+  import MatrixServerWeb.Error
 
   @supported_versions ["r0.6.1"]
 

lib/matrix_server_web/client/controllers/login_controller.ex

@@ -1,11 +1,11 @@
 defmodule MatrixServerWeb.Client.LoginController do
   use MatrixServerWeb, :controller
 
-  import MatrixServerWeb.Plug.Error
+  import MatrixServerWeb.Error
   import Ecto.Changeset
 
   alias MatrixServer.{Repo, Account}
-  alias MatrixServerWeb.Request.Login
+  alias MatrixServerWeb.Client.Request.Login
   alias Ecto.Changeset
 
   @login_type "m.login.password"

lib/matrix_server_web/client/controllers/register_controller.ex

@@ -1,11 +1,11 @@
 defmodule MatrixServerWeb.Client.RegisterController do
   use MatrixServerWeb, :controller
 
-  import MatrixServerWeb.Plug.Error
+  import MatrixServerWeb.Error
   import Ecto.Changeset
 
   alias MatrixServer.{Repo, Account}
-  alias MatrixServerWeb.Request.Register
+  alias MatrixServerWeb.Client.Request.Register
   alias Ecto.Changeset
 
   @register_type "m.login.dummy"

lib/matrix_server_web/client/controllers/room_controller.ex

@@ -1,11 +1,11 @@
 defmodule MatrixServerWeb.Client.RoomController do
   use MatrixServerWeb, :controller
 
-  import MatrixServerWeb.Plug.Error
+  import MatrixServerWeb.Error
   import Ecto.Changeset
 
   alias MatrixServer.Room
-  alias MatrixServerWeb.Request.{CreateRoom}
+  alias MatrixServerWeb.Client.Request.CreateRoom
   alias Ecto.Changeset
   alias Plug.Conn
 

lib/matrix_server_web/client/request/create_room.ex

@@ -1,4 +1,4 @@
-defmodule MatrixServerWeb.Request.CreateRoom do
+defmodule MatrixServerWeb.Client.Request.CreateRoom do
   use Ecto.Schema
 
   import Ecto.Changeset

lib/matrix_server_web/client/request/login.ex

@@ -1,4 +1,4 @@
-defmodule MatrixServerWeb.Request.Login do
+defmodule MatrixServerWeb.Client.Request.Login do
   use Ecto.Schema
 
   import Ecto.Changeset

lib/matrix_server_web/client/request/register.ex

@@ -1,4 +1,4 @@
-defmodule MatrixServerWeb.Request.Register do
+defmodule MatrixServerWeb.Client.Request.Register do
   use Ecto.Schema
 
   import Ecto.Changeset

lib/matrix_server_web/error.ex

@@ -1,4 +1,4 @@
-defmodule MatrixServerWeb.Plug.Error do
+defmodule MatrixServerWeb.Error do
   import Plug.Conn
   import Phoenix.Controller, only: [json: 2]
 

lib/matrix_server_web/federation/authenticate_server.ex

@@ -1,5 +1,5 @@
-defmodule MatrixServerWeb.AuthenticateServer do
-  import MatrixServerWeb.Plug.Error
+defmodule MatrixServerWeb.Federation.AuthenticateServer do
+  import MatrixServerWeb.Error
 
   alias MatrixServer.{SigningKey, ServerKeyInfo}
 
@@ -71,7 +71,7 @@ defmodule MatrixServerWeb.AuthenticateServer do
         action = action_name(conn)
 
         if action not in unquote(except) do
-          case MatrixServerWeb.AuthenticateServer.authenticate(conn) do
+          case MatrixServerWeb.Federation.AuthenticateServer.authenticate(conn) do
             {origin, _key, _sig} ->
               conn = Plug.Conn.assign(conn, :origin, origin)
               apply(__MODULE__, action, [conn, conn.params])

lib/matrix_server_web/federation/controllers/key_controller.ex

@@ -1,7 +1,7 @@
 defmodule MatrixServerWeb.Federation.KeyController do
   use MatrixServerWeb, :controller
 
-  import MatrixServerWeb.Plug.Error
+  import MatrixServerWeb.Error
 
   alias MatrixServer.KeyServer
 

lib/matrix_server_web/federation/controllers/query_controller.ex

@@ -1,8 +1,8 @@
 defmodule MatrixServerWeb.Federation.QueryController do
   use MatrixServerWeb, :controller
-  use MatrixServerWeb.AuthenticateServer
+  use MatrixServerWeb.Federation.AuthenticateServer
 
-  import MatrixServerWeb.Plug.Error
+  import MatrixServerWeb.Error
   import Ecto.Query
 
   alias MatrixServer.{Repo, Account}

lib/matrix_server_web/federation/http_client.ex

@@ -1,20 +1,26 @@
-defmodule MatrixServerWeb.FederationClient do
+defmodule MatrixServerWeb.Federation.HTTPClient do
   use Tesla
 
   alias MatrixServerWeb.Endpoint
   alias MatrixServerWeb.Federation.Request.GetSigningKeys
+  alias MatrixServerWeb.Federation.Middleware.SignRequest
   alias MatrixServerWeb.Router.Helpers, as: RouteHelpers
 
   # TODO: Maybe create database-backed homeserver struct to pass to client function.
-
-  @middleware [
-    Tesla.Middleware.JSON
-  ]
+  # TODO: Fix error propagation.
 
   @adapter {Tesla.Adapter.Finch, name: MatrixServerWeb.HTTPClient}
 
   def client(server_name) do
-    Tesla.client([{Tesla.Middleware.BaseUrl, "http://" <> server_name} | @middleware], @adapter)
+    Tesla.client(
+      [
+        {Tesla.Middleware.Opts, [server_name: server_name]},
+        SignRequest,
+        {Tesla.Middleware.BaseUrl, "http://" <> server_name},
+        Tesla.Middleware.JSON
+      ],
+      @adapter
+    )
   end
 
   def get_signing_keys(client) do
@@ -45,30 +51,11 @@ defmodule MatrixServerWeb.FederationClient do
     end
   end
 
-  # TODO: Create tesla middleware to add signature and headers.
-  def query_profile(client, server_name, user_id, field \\ nil) do
-    origin = MatrixServer.server_name()
+  def query_profile(client, user_id, field \\ nil) do
     path = RouteHelpers.query_path(Endpoint, :profile) |> Tesla.build_url(user_id: user_id)
     path = if field, do: Tesla.build_url(path, field: field), else: path
 
-    object_to_sign = %{
-      method: "GET",
-      uri: URI.decode_www_form(path),
-      origin: origin,
-      destination: server_name
-    }
-
-    {:ok, signature, key_id} = MatrixServer.KeyServer.sign_object(object_to_sign)
-    signatures = %{origin => %{key_id => signature}}
-    auth_headers = create_signature_authorization_headers(signatures, origin)
-
-    Tesla.get(client, path, headers: auth_headers)
-  end
-
-  defp create_signature_authorization_headers(signatures, origin) do
-    Enum.map(signatures[origin], fn {key, sig} ->
-      {"Authorization", "X-Matrix origin=#{origin},key=\"#{key}\",sig=\"#{sig}\""}
-    end)
+    Tesla.get(client, path)
   end
 
   defp tesla_request(method, client, path, request_schema) do

lib/matrix_server_web/federation/sign_request_middleware.ex

@@ -0,0 +1,38 @@
+defmodule MatrixServerWeb.Federation.Middleware.SignRequest do
+  @behaviour Tesla.Middleware
+
+  def call(%Tesla.Env{opts: opts} = env, next, _opts) do
+    sign = Keyword.get(opts, :sign, true)
+
+    case sign_request(env, sign) do
+      %Tesla.Env{} = env -> Tesla.run(env, next)
+      :error -> {:error, :sign_request}
+    end
+  end
+
+  defp sign_request(env, false), do: env
+
+  defp sign_request(%Tesla.Env{method: method, url: path, opts: opts} = env, true) do
+    origin = MatrixServer.server_name()
+
+    object_to_sign = %{
+      method: Atom.to_string(method) |> String.upcase(),
+      origin: origin,
+      uri: URI.decode_www_form(path),
+      destination: Keyword.fetch!(opts, :server_name)
+    }
+
+    with {:ok, sig, key_id} <- MatrixServer.KeyServer.sign_object(object_to_sign) do
+      sigs = %{origin => %{key_id => sig}}
+      auth_headers = create_signature_authorization_headers(sigs, origin)
+
+      Tesla.put_headers(env, auth_headers)
+    end
+  end
+
+  defp create_signature_authorization_headers(signatures, origin) do
+    Enum.map(signatures[origin], fn {key, sig} ->
+      {"Authorization", "X-Matrix origin=#{origin},key=\"#{key}\",sig=\"#{sig}\""}
+    end)
+  end
+end

lib/matrix_server_web/router.ex

@@ -1,7 +1,7 @@
 defmodule MatrixServerWeb.Router do
   use MatrixServerWeb, :router
 
-  alias MatrixServerWeb.Plug.AuthenticateClient
+  alias MatrixServerWeb.Client.AuthenticateClientPlug
 
   # TODO: might be able to handle malformed JSON with custom body reader:
   # https://elixirforum.com/t/write-malformed-json-in-the-body-plug/30578/13
@@ -12,7 +12,7 @@ defmodule MatrixServerWeb.Router do
 
   pipeline :authenticate_client do
     plug :accepts, ["json"]
-    plug AuthenticateClient
+    plug AuthenticateClientPlug
   end
 
   pipeline :authenticate_server do