From 54dbcfe02a05a75d7fe7591335df74743930182d Mon Sep 17 00:00:00 2001
From: Alex Gleason <alex@alexgleason.me>
Date: Sat, 17 Jul 2021 14:55:05 -0500
Subject: [PATCH] AdminAPI: add DELETE /instances/:instance to delete all
 content from a remote instance

---
 docs/development/API/admin_api.md              | 16 ++++++++++++++++
 .../controllers/instance_controller.ex         | 13 +++++++++++++
 lib/pleroma/web/router.ex                      |  1 +
 .../controllers/instance_controller_test.exs   | 18 ++++++++++++++++++
 4 files changed, 48 insertions(+)

diff --git a/docs/development/API/admin_api.md b/docs/development/API/admin_api.md
index 8f855d251..82483fae7 100644
--- a/docs/development/API/admin_api.md
+++ b/docs/development/API/admin_api.md
@@ -319,6 +319,22 @@ Note: Available `:permission_group` is currently moderator and admin. 404 is ret
 }
 ```
 
+## `DELETE /api/v1/pleroma/admin/instances/:instance`
+
+### Delete all users and activities from a remote instance
+
+Note: this will trigger a job to remove instance content in the background.
+It may take some time.
+
+- Params:
+  - `instance`: remote instance host
+- Response:
+  - The `instance` name as a string
+
+```json
+"lain.com"
+```
+
 ## `GET /api/v1/pleroma/admin/statuses`
 
 ### Retrives all latest statuses
diff --git a/lib/pleroma/web/admin_api/controllers/instance_controller.ex b/lib/pleroma/web/admin_api/controllers/instance_controller.ex
index ad6ea89ef..2fc2fb442 100644
--- a/lib/pleroma/web/admin_api/controllers/instance_controller.ex
+++ b/lib/pleroma/web/admin_api/controllers/instance_controller.ex
@@ -7,6 +7,7 @@ defmodule Pleroma.Web.AdminAPI.InstanceController do
 
   import Pleroma.Web.ControllerHelper, only: [fetch_integer_param: 3]
 
+  alias Pleroma.Instances.Instance
   alias Pleroma.Web.ActivityPub.ActivityPub
   alias Pleroma.Web.AdminAPI
   alias Pleroma.Web.Plugs.OAuthScopesPlug
@@ -21,6 +22,12 @@ defmodule Pleroma.Web.AdminAPI.InstanceController do
     when action in [:list_instance_statuses]
   )
 
+  plug(
+    OAuthScopesPlug,
+    %{scopes: ["admin:write:accounts", "admin:write:statuses"]}
+    when action in [:delete_instance]
+  )
+
   action_fallback(AdminAPI.FallbackController)
 
   def list_instance_statuses(conn, %{"instance" => instance} = params) do
@@ -41,6 +48,12 @@ def list_instance_statuses(conn, %{"instance" => instance} = params) do
     |> render("index.json", %{total: result[:total], activities: result[:items], as: :activity})
   end
 
+  def delete_instance(conn, %{"instance" => instance}) do
+    with {:ok, _job} <- Instance.delete_users_and_activities(instance) do
+      json(conn, instance)
+    end
+  end
+
   defp page_params(params) do
     {
       fetch_integer_param(params, "page", 1),
diff --git a/lib/pleroma/web/router.ex b/lib/pleroma/web/router.ex
index dbc7df104..1f465b697 100644
--- a/lib/pleroma/web/router.ex
+++ b/lib/pleroma/web/router.ex
@@ -210,6 +210,7 @@ defmodule Pleroma.Web.Router do
     get("/users/:nickname/chats", AdminAPIController, :list_user_chats)
 
     get("/instances/:instance/statuses", InstanceController, :list_instance_statuses)
+    delete("/instances/:instance", InstanceController, :delete_instance)
 
     get("/instance_document/:name", InstanceDocumentController, :show)
     patch("/instance_document/:name", InstanceDocumentController, :update)
diff --git a/test/pleroma/web/admin_api/controllers/instance_controller_test.exs b/test/pleroma/web/admin_api/controllers/instance_controller_test.exs
index b70efcf23..42248c6bd 100644
--- a/test/pleroma/web/admin_api/controllers/instance_controller_test.exs
+++ b/test/pleroma/web/admin_api/controllers/instance_controller_test.exs
@@ -8,6 +8,8 @@ defmodule Pleroma.Web.AdminAPI.InstanceControllerTest do
 
   import Pleroma.Factory
 
+  alias Pleroma.Repo
+  alias Pleroma.Tests.ObanHelpers
   alias Pleroma.Web.CommonAPI
 
   setup_all do
@@ -61,4 +63,20 @@ test "GET /instances/:instance/statuses", %{conn: conn} do
       assert length(activities) == 3
     end
   end
+
+  test "DELETE /instances/:instance", %{conn: conn} do
+    user = insert(:user, nickname: "lain@lain.com")
+    post = insert(:note_activity, user: user)
+
+    response =
+      conn
+      |> delete("/api/pleroma/admin/instances/lain.com")
+      |> json_response(200)
+
+    [:ok] = ObanHelpers.perform_all()
+
+    assert response == "lain.com"
+    refute Repo.reload(user).is_active
+    refute Repo.reload(post)
+  end
 end