FEATURE: Add reject follower action (#123)

app/controllers/discourse_activity_pub/actor_controller.rb

@@ -9,12 +9,12 @@ class ActorController < ApplicationController
 
     include DiscourseActivityPub::EnabledVerification
 
-    before_action :ensure_admin, only: %i[follow unfollow find_by_handle]
+    before_action :ensure_admin, only: %i[follow unfollow reject find_by_handle]
     before_action :ensure_site_enabled
     before_action :find_actor
     before_action :ensure_model_enabled
     before_action :ensure_can_access
-    before_action :find_target_actor, only: %i[follow unfollow]
+    before_action :find_target_actor, only: %i[follow unfollow reject]
 
     def show
       render_serialized(@actor, DiscourseActivityPub::ActorSerializer, include_model: true)
@@ -44,6 +44,18 @@ def unfollow
       end
     end
 
+    def reject
+      # Currently, we only process rejections of existing follows.
+      # See further https://github.com/mastodon/mastodon/issues/5708
+      return render_actor_error("not_following_actor", 404) if !@target_actor.following?(@actor)
+
+      if FollowHandler.reject(@actor.id, @target_actor.id)
+        render json: success_json
+      else
+        render json: failed_json
+      end
+    end
+
     def find_by_handle
       params.require(:handle)
 

app/models/discourse_activity_pub_activity.rb

@@ -95,14 +95,31 @@ def before_deliver
   end
 
   def after_deliver(delivered = true)
-    return self.destroy! if !delivered && local? && ap.follow?
+    return unless local?
+    return self.destroy! if !delivered && ap.follow?
 
-    if delivered && local? && ap.undo? && object.ap.follow?
+    if delivered && undo_follow?
       DiscourseActivityPubFollow.where(
         follower_id: actor_id,
         followed_id: object.object.id,
       ).destroy_all
     end
+
+    # We destroy our local follow whether or not our follow rejection was delivered.
+    if reject_follow?
+      DiscourseActivityPubFollow.where(
+        follower_id: object.actor.id,
+        followed_id: actor_id,
+      ).destroy_all
+    end
+  end
+
+  def undo_follow?
+    ap.undo? && object.ap.follow?
+  end
+
+  def reject_follow?
+    ap.reject? && object.ap.follow?
   end
 
   def after_scheduled(scheduled_at, _activity = nil)

assets/javascripts/discourse/components/activity-pub-follow-btn.gjs

@@ -5,13 +5,15 @@ import { dasherize } from "@ember/string";
 import DButton from "discourse/components/d-button";
 import I18n from "I18n";
 import ActivityPubActorFollowModal from "../components/modal/activity-pub-actor-follow";
+import ActivityPubActorRejectModal from "../components/modal/activity-pub-actor-reject";
 import ActivityPubActorUnfollowModal from "../components/modal/activity-pub-actor-unfollow";
 import ActivityPubFollowModal from "../components/modal/activity-pub-follow";
 
 const modalMap = {
   follow: ActivityPubFollowModal,
   actor_follow: ActivityPubActorFollowModal,
   actor_unfollow: ActivityPubActorUnfollowModal,
+  actor_reject: ActivityPubActorRejectModal,
 };
 
 export default class ActivityPubFollowBtn extends Component {

assets/javascripts/discourse/components/modal/activity-pub-actor-reject.hbs

@@ -0,0 +1,24 @@
+<DModal
+  @closeModal={{@closeModal}}
+  @title={{this.title}}
+  class="activity-pub-actor-reject-modal"
+>
+  <:body>
+    <div class="activity-pub-actor-reject">
+      {{i18n
+        "discourse_activity_pub.actor_reject.confirm"
+        actor=@model.actor.name
+        follower=@model.follower.handle
+      }}
+    </div>
+  </:body>
+
+  <:footer>
+    <DButton
+      @action={{action "reject"}}
+      @label="discourse_activity_pub.actor_reject.label"
+      class="btn-primary"
+    />
+    <DModalCancel @close={{@closeModal}} />
+  </:footer>
+</DModal>

assets/javascripts/discourse/components/modal/activity-pub-actor-reject.js

@@ -0,0 +1,18 @@
+import Component from "@glimmer/component";
+import { action } from "@ember/object";
+import I18n from "I18n";
+
+export default class ActivityPubActorReject extends Component {
+  get title() {
+    return I18n.t("discourse_activity_pub.actor_reject.modal_title", {
+      actor: this.args.model.actor?.name,
+    });
+  }
+
+  @action
+  reject() {
+    const model = this.args.model;
+    model.reject(model.actor, model.follower);
+    this.args.closeModal();
+  }
+}

assets/javascripts/discourse/controllers/activity-pub-actor-followers.js

@@ -13,6 +13,14 @@ export default class ActivityPubActorFollowers extends Controller {
 
   @notEmpty("actors") hasActors;
 
+  get tableClass() {
+    let result = "activity-pub-follow-table followers";
+    if (this.currentUser.admin) {
+      result += " show-controls";
+    }
+    return result;
+  }
+
   @action
   loadMore() {
     if (!this.loadMoreUrl || this.total <= this.actors.length) {

assets/javascripts/discourse/models/activity-pub-actor.js

@@ -127,6 +127,18 @@ ActivityPubActor.reopenClass({
       .catch(popupAjaxError);
   },
 
+  reject(actorId, targetActorId) {
+    return ajax({
+      url: `${actorClientPath}/${actorId}/reject`,
+      type: "POST",
+      data: {
+        target_actor_id: targetActorId,
+      },
+    })
+      .then((response) => !!response?.success)
+      .catch(popupAjaxError);
+  },
+
   list(actorId, params, listType) {
     const queryParams = new URLSearchParams();
 

assets/javascripts/discourse/routes/activity-pub-actor.js

@@ -3,14 +3,14 @@ import { inject as service } from "@ember/service";
 import DiscourseRoute from "discourse/routes/discourse";
 import ActivityPubActor from "../models/activity-pub-actor";
 
-export default DiscourseRoute.extend({
-  router: service(),
-  site: service(),
-  store: service(),
+export default class ActivityPubActorRoute extends DiscourseRoute {
+  @service router;
+  @service site;
+  @service store;
 
   model(params) {
     return ActivityPubActor.find(params.actor_id);
-  },
+  }
 
   setupController(controller, model) {
     const actor = model;
@@ -34,7 +34,7 @@ export default DiscourseRoute.extend({
       props.canCreateTopicOnTag = !actor.model.staff || this.currentUser?.staff;
     }
     controller.setProperties(props);
-  },
+  }
 
   @action
   follow(actor, followActor) {
@@ -44,7 +44,7 @@ export default DiscourseRoute.extend({
       );
       return result;
     });
-  },
+  }
 
   @action
   unfollow(actor, followedActor) {
@@ -56,5 +56,15 @@ export default DiscourseRoute.extend({
         return result;
       }
     );
-  },
-});
+  }
+
+  @action
+  reject(actor, follower) {
+    return ActivityPubActor.reject(actor.id, follower.id).then((result) => {
+      this.controllerFor(this.router.currentRouteName).actors.removeObject(
+        follower
+      );
+      return result;
+    });
+  }
+}

assets/javascripts/discourse/templates/activity-pub-actor-followers.hbs

@@ -4,7 +4,7 @@
   class="activity-pub-followers-container"
 >
   {{#if this.hasActors}}
-    <ResponsiveTable @className="activity-pub-follow-table followers">
+    <ResponsiveTable @className={{this.tableClass}}>
       <:header>
         <TableHeaderToggle
           @field="actor"
@@ -27,29 +27,50 @@
           @order={{this.order}}
           @asc={{this.asc}}
         />
+        {{#if this.currentUser.admin}}
+          <div
+            class="directory-table__column-header activity-pub-follow-table-actions"
+          >
+            <span class="text">{{i18n
+                "discourse_activity_pub.follow_table.actions"
+              }}</span>
+          </div>
+        {{/if}}
       </:header>
       <:body>
-        {{#each this.actors as |actor|}}
+        {{#each this.actors as |follower|}}
           <div class="directory-table__row activity-pub-follow-table-row">
             <div class="directory-table__cell activity-pub-follow-table-actor">
-              <ActivityPubActor @actor={{actor}} />
+              <ActivityPubActor @actor={{follower}} />
             </div>
             <div class="directory-table__cell activity-pub-follow-table-user">
-              {{#if actor.model}}
+              {{#if follower.model}}
                 <a
                   class="avatar"
-                  href={{concat "/u/" actor.model.username}}
-                  data-user-card={{actor.model.username}}
+                  href={{concat "/u/" follower.model.username}}
+                  data-user-card={{follower.model.username}}
                 >
-                  {{avatar actor.model imageSize="small"}}
+                  {{avatar follower.model imageSize="small"}}
                 </a>
               {{/if}}
             </div>
             <div
               class="directory-table__cell activity-pub-follow-table-followed-at"
             >
-              {{bound-date actor.followed_at}}
+              {{bound-date follower.followed_at}}
             </div>
+            {{#if this.currentUser.admin}}
+              <div
+                class="directory-table__cell activity-pub-follow-table-actions"
+              >
+                <ActivityPubFollowBtn
+                  @actor={{actor}}
+                  @follower={{follower}}
+                  @reject={{route-action "reject"}}
+                  @type="actor_reject"
+                />
+              </div>
+            {{/if}}
           </div>
         {{/each}}
       </:body>

assets/stylesheets/common/common.scss

@@ -331,6 +331,9 @@ body.user-preferences-activity-pub-page {
 .activity-pub-follow-table {
   &.followers {
     grid-template-columns: minmax(13em, 3fr) repeat(2, 110px);
+    &.show-controls {
+      grid-template-columns: minmax(13em, 3fr) repeat(3, 110px);
+    }
   }
   &.follows {
     grid-template-columns: minmax(13em, 3fr) repeat(3, 110px);

config/locales/client.en.yml

@@ -130,11 +130,17 @@ en:
         title: Unfollow for %{actor} via ActivityPub
         modal_title: Confirm Unfollow
         confirm: Are you sure you want %{actor} to unfollow %{followed_actor}?
+      actor_reject:
+        label: Reject
+        title: Reject follow of %{actor} via ActivityPub
+        modal_title: Confirm Reject Follow
+        confirm: Are you sure you want to reject %{follower} from following %{actor}?
       follow_table:
         actor: Actor
         user: User
         followed_at: Followed
         follow_pending: pending
+        actions: Actions
       visibility:
         label:
           private: Followers Only

config/locales/server.en.yml

@@ -131,13 +131,15 @@ en:
         cant_follow_target_actor: "Actor cant follow the target actor"
         username_required: An ActivityPub username is required to create an actor.
         full_topic_must_be_public: "Full topic publication requires public publication."
+        not_following_actor: "Target actor is not following the actor"
       warning:
         cant_create_model_for_actor_type: "Cannot create a model for %{actor_type} %{actor_id}"
         cant_create_actor_for_model_type: "Cannot create an actor for %{model_type} %{model_id}"
         not_allowed_to_create_actor_for_model: "Not allowed to create an actor for %{model_id}"
         no_options: "No options passed to ActorHandler"
         invalid_username: "Username must be %{min_length} to %{max_length} letters, numbers, dashes or underscores."
         username_taken: "That username is already taken on this server."
+        user_not_authorized: "User not authorized"
     auth:
       error:
         invalid_oauth_domain: "Invalid ActivityPub OAuth domain"

config/routes.rb

@@ -22,6 +22,7 @@
       get ":actor_id/follows" => "actor#follows"
       post ":actor_id/follow" => "actor#follow", :defaults => { format: :json }
       delete ":actor_id/follow" => "actor#unfollow", :defaults => { format: :json }
+      post ":actor_id/reject" => "actor#reject", :defaults => { format: :json }
       get ":actor_id/find-by-handle" => "actor#find_by_handle", :defaults => { format: :json }
     end
   end

lib/discourse_activity_pub/ap/activity.rb

@@ -112,6 +112,10 @@ def follow?
         type == Follow.type
       end
 
+      def reject?
+        type == Reject.type
+      end
+
       def announce?
         type == Announce.type
       end