Federate client profile requests

lib/architex.ex

@@ -174,9 +174,9 @@ defmodule Architex do
   @doc """
   Validate a changeset's field where the reason for invalidation is not needed.
   """
-  @spec validate_change_simple(Ecto.Changeset.t(), atom(), (term() -> boolean())) ::
+  @spec validate_change_truthy(Ecto.Changeset.t(), atom(), (term() -> boolean())) ::
           Ecto.Changeset.t()
-  def validate_change_simple(changeset, field, func) do
+  def validate_change_truthy(changeset, field, func) do
     augmented_func = fn _, val ->
       if func.(val), do: [], else: [{field, "invalid"}]
     end

lib/architex_web/client/controllers/profile_controller.ex

@@ -7,6 +7,7 @@ defmodule ArchitexWeb.Client.ProfileController do
 
   alias Architex.{Repo, Account}
   alias Architex.Types.UserId
+  alias ArchitexWeb.Federation.HTTPClient
   alias Plug.Conn
   alias Ecto.Changeset
 
@@ -33,8 +34,15 @@ defmodule ArchitexWeb.Client.ProfileController do
               put_error(conn, :not_found, "User was not found.")
           end
         else
-          # TODO: Use federation to lookup information.
-          put_error(conn, :not_found, "User was not found.")
+          case HTTPClient.client(domain) |> HTTPClient.query_profile(user_id) do
+            {:ok, response} ->
+              conn
+              |> put_status(200)
+              |> json(response)
+
+            {:error, _, _} ->
+              put_error(conn, :not_found, "User was not found.")
+          end
         end
 
       :error ->
@@ -77,8 +85,15 @@ defmodule ArchitexWeb.Client.ProfileController do
               put_error(conn, :not_found, "User was not found.")
           end
         else
-          # TODO: Use federation to lookup information.
-          put_error(conn, :not_found, "User was not found.")
+          case HTTPClient.client(domain) |> HTTPClient.query_profile(user_id, Atom.to_string(property_key)) do
+            {:ok, response} ->
+              conn
+              |> put_status(200)
+              |> json(response)
+
+            {:error, _, _} ->
+              put_error(conn, :not_found, "User was not found.")
+          end
         end
 
       :error ->
@@ -108,7 +123,12 @@ defmodule ArchitexWeb.Client.ProfileController do
     update_property(conn, :avatar_url, avatar_url, user_id)
   end
 
-  defp update_property(%Conn{assigns: %{account: account}} = conn, property_key, property, user_id) do
+  defp update_property(
+         %Conn{assigns: %{account: account}} = conn,
+         property_key,
+         property,
+         user_id
+       ) do
     if Account.get_mxid(account) == user_id do
       account
       |> Changeset.change([{property_key, property}])

lib/architex_web/federation/controllers/query_controller.ex

@@ -38,15 +38,27 @@ defmodule ArchitexWeb.Federation.QueryController do
   Action for GET /_matrix/federation/v1/query/profile.
   """
   def profile(conn, params) do
-    with {:ok, %ProfileRequest{user_id: %UserId{localpart: localpart, domain: domain}}} <-
+    with {:ok,
+          %ProfileRequest{user_id: %UserId{localpart: localpart, domain: domain}, field: field}} <-
            ProfileRequest.validate(params) do
       if domain == Architex.server_name() do
         case Repo.one(from a in Account, where: a.localpart == ^localpart) do
-          %Account{} ->
-            # TODO: Return displayname and avatar_url when we implement them.
+          %Account{displayname: displayname, avatar_url: avatar_url} ->
+            data = %{}
+
+            data =
+              if field == "displayname" or (field == nil and displayname != nil),
+                do: Map.put(data, :displayname, displayname),
+                else: data
+
+            data =
+              if field == "avatar_url" or (field == nil and avatar_url != nil),
+                do: Map.put(data, :avatar_url, avatar_url),
+                else: data
+
             conn
             |> put_status(200)
-            |> json(%{})
+            |> json(data)
 
           nil ->
             put_error(conn, :not_found, "User does not exist.")

lib/architex_web/federation/http_client.ex

@@ -1,4 +1,9 @@
 defmodule ArchitexWeb.Federation.HTTPClient do
+  @moduledoc """
+  This module provides functions to interact with other homeservers
+  using the Matrix federation API.
+  """
+  # TODO: Investigate request timeouts.
   use Tesla
 
   alias ArchitexWeb.Endpoint
@@ -6,11 +11,27 @@ defmodule ArchitexWeb.Federation.HTTPClient do
   alias ArchitexWeb.Federation.Middleware.SignRequest
   alias ArchitexWeb.Router.Helpers, as: RouteHelpers
 
-  # TODO: Maybe create database-backed homeserver struct to pass to client function.
-  # TODO: Fix error propagation.
+  @type t :: schema_response() | map_response()
+
+  @type schema_response ::
+          {:ok, struct()}
+          | {:error, :status, Tesla.Env.t()}
+          | {:error, :validation, Ecto.Changeset.t()}
+          | {:error, :request, any()}
+
+  @type map_response ::
+          {:ok, map()}
+          | {:error, :status, Tesla.Env.t()}
+          | {:error, :validation, Ecto.Changeset.t()}
+          | {:error, :request, any()}
 
   @adapter {Tesla.Adapter.Finch, name: ArchitexWeb.HTTPClient}
 
+  @doc """
+  Get a Tesla client for the given server name, to be used for
+  interacting with other homeservers.
+  """
+  @spec client(String.t()) :: Tesla.Client.t()
   def client(server_name) do
     Tesla.client(
       [
@@ -23,6 +44,10 @@ defmodule ArchitexWeb.Federation.HTTPClient do
     )
   end
 
+  @doc """
+  Get the signing keys of a homeserver.
+  """
+  @spec get_signing_keys(Tesla.Client.t()) :: {:ok, GetSigningKeys.t()} | :error
   def get_signing_keys(client) do
     path = RouteHelpers.key_path(Endpoint, :get_signing_keys)
 
@@ -53,40 +78,61 @@ defmodule ArchitexWeb.Federation.HTTPClient do
     end
   end
 
+  @doc """
+  Get the profile of a user.
+  """
+  @spec query_profile(Tesla.Client.t(), String.t(), String.t() | nil) :: map_response()
   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
 
-    Tesla.get(client, path)
+    tesla_request(:get, client, path)
   end
 
-  def get_event(client, event_id) do
-    path = RouteHelpers.event_path(Endpoint, :event, event_id)
+  # def get_event(client, event_id) do
+  #   path = RouteHelpers.event_path(Endpoint, :event, event_id)
 
-    Tesla.get(client, path)
-  end
+  #   Tesla.get(client, path)
+  # end
 
-  def get_state(client, room_id, event_id) do
-    path =
-      RouteHelpers.event_path(Endpoint, :state, room_id) |> Tesla.build_url(event_id: event_id)
+  # def get_state(client, room_id, event_id) do
+  #   path =
+  #     RouteHelpers.event_path(Endpoint, :state, room_id) |> Tesla.build_url(event_id: event_id)
 
-    Tesla.get(client, path)
-  end
+  #   Tesla.get(client, path)
+  # end
 
-  def get_state_ids(client, room_id, event_id) do
-    path =
-      RouteHelpers.event_path(Endpoint, :state_ids, room_id)
-      |> Tesla.build_url(event_id: event_id)
+  # def get_state_ids(client, room_id, event_id) do
+  #   path =
+  #     RouteHelpers.event_path(Endpoint, :state_ids, room_id)
+  #     |> Tesla.build_url(event_id: event_id)
 
-    Tesla.get(client, path)
-  end
+  #   Tesla.get(client, path)
+  # end
 
-  defp tesla_request(method, client, path, request_schema) do
-    with {:ok, %Tesla.Env{body: body}} <- Tesla.request(client, url: path, method: method),
-         %Ecto.Changeset{valid?: true} = cs <- apply(request_schema, :changeset, [body]) do
-      {:ok, Ecto.Changeset.apply_changes(cs)}
-    else
-      _ -> :error
+  # Perform a Tesla request and validate the response with the given
+  # Ecto schema struct.
+  @spec tesla_request(atom(), Tesla.Client.t(), String.t(), module()) :: t()
+  defp tesla_request(method, client, path, request_schema \\ nil) do
+    case Tesla.request(client, url: path, method: method) do
+      {:ok, %Tesla.Env{status: status} = env} when status != 200 ->
+        {:error, :status, env}
+
+      {:ok, %Tesla.Env{body: body}} ->
+        if request_schema do
+          case apply(request_schema, :parse, [body]) do
+            {:ok, response} ->
+              {:ok, response}
+
+            {:error, changeset} ->
+              {:error, :validation, changeset}
+          end
+        else
+          {:ok, body}
+        end
+
+      {:error, tesla_error} ->
+        {:error, :request, tesla_error}
     end
   end
 end

lib/architex_web/federation/request/get_signing_keys.ex

@@ -1,7 +1,13 @@
 defmodule ArchitexWeb.Federation.Request.GetSigningKeys do
-  use Ecto.Schema
+  use ArchitexWeb.Request
 
-  import Ecto.Changeset
+  @type t :: %__MODULE__{
+          server_name: String.t(),
+          verify_keys: %{optional(String.t()) => %{String.t() => String.t()}},
+          old_verify_keys: %{optional(String.t()) => map()},
+          signatures: %{optional(String.t()) => %{optional(String.t()) => String.t()}},
+          valid_until_ts: integer()
+        }
 
   @primary_key false
   embedded_schema do
@@ -12,17 +18,16 @@ defmodule ArchitexWeb.Federation.Request.GetSigningKeys do
     field :valid_until_ts, :integer
   end
 
-  def changeset(params) do
-    # TODO: There must be a better way to validate embedded maps?
-    %__MODULE__{}
+  def changeset(data, params) do
+    data
     |> cast(params, [:server_name, :verify_keys, :old_verify_keys, :signatures, :valid_until_ts])
     |> validate_required([:server_name, :verify_keys, :valid_until_ts])
-    |> Architex.validate_change_simple(:verify_keys, fn map ->
+    |> Architex.validate_change_truthy(:verify_keys, fn map ->
       Enum.all?(map, fn {_, map} ->
         is_map_key(map, "key")
       end)
     end)
-    |> Architex.validate_change_simple(:old_verify_keys, fn map ->
+    |> Architex.validate_change_truthy(:old_verify_keys, fn map ->
       Enum.all?(map, fn
         {_, %{"key" => key, "expired_ts" => expired_ts}}
         when is_binary(key) and is_integer(expired_ts) ->