Admin API: Allow querying user by ID

CHANGELOG.md

@@ -9,6 +9,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Mastodon API: Support for the [`tagged` filter](https://github.com/tootsuite/mastodon/pull/9755) in [`GET /api/v1/accounts/:id/statuses`](https://docs.joinmastodon.org/api/rest/accounts/#get-api-v1-accounts-id-statuses)
 - Admin API: Return users' tags when querying reports
 - Admin API: Return avatar and display name when querying users
+- Admin API: Allow querying user by ID
 
 ### Fixed
 - Not being able to pin unlisted posts

docs/api/admin_api.md

@@ -187,6 +187,17 @@ Note: Available `:permission_group` is currently moderator and admin. 404 is ret
   - On failure: `Not found`
   - On success: JSON of the user
 
+## `/api/pleroma/admin/users/:id`
+
+### Retrive the details of a user
+
+- Method: `GET`
+- Params:
+  - `id`
+- Response:
+  - On failure: `Not found`
+  - On success: JSON of the user
+
 ## `/api/pleroma/admin/relay`
 
 ### Follow a Relay

lib/pleroma/web/admin_api/admin_api_controller.ex

@@ -74,7 +74,7 @@ def user_create(
   end
 
   def user_show(conn, %{"nickname" => nickname}) do
-    with %User{} = user <- User.get_cached_by_nickname(nickname) do
+    with %User{} = user <- User.get_cached_by_nickname_or_id(nickname) do
       conn
       |> json(AccountView.render("show.json", %{user: user}))
     else