From cc8888dea20bd520a0169549d2a1d0fd7469d4a1 Mon Sep 17 00:00:00 2001
From: Mouse Reeve <mousereeve@riseup.net>
Date: Sat, 23 Jan 2021 11:03:10 -0800
Subject: [PATCH] Adds incoming handler for blocking

---
 bookwyrm/activitypub/__init__.py |  2 +-
 bookwyrm/activitypub/verbs.py    |  4 ++++
 bookwyrm/incoming.py             | 18 ++++++++++++++++++
 bookwyrm/models/relationship.py  |  2 +-
 bookwyrm/tests/test_incoming.py  | 26 ++++++++++++++++++++++++++
 5 files changed, 50 insertions(+), 2 deletions(-)

diff --git a/bookwyrm/activitypub/__init__.py b/bookwyrm/activitypub/__init__.py
index a4fef41e5..a74397225 100644
--- a/bookwyrm/activitypub/__init__.py
+++ b/bookwyrm/activitypub/__init__.py
@@ -14,7 +14,7 @@ from .person import Person, PublicKey
 from .response import ActivitypubResponse
 from .book import Edition, Work, Author
 from .verbs import Create, Delete, Undo, Update
-from .verbs import Follow, Accept, Reject
+from .verbs import Follow, Accept, Reject, Block
 from .verbs import Add, AddBook, Remove
 
 # this creates a list of all the Activity types that we can serialize,
diff --git a/bookwyrm/activitypub/verbs.py b/bookwyrm/activitypub/verbs.py
index 7c6279279..6977ee8e8 100644
--- a/bookwyrm/activitypub/verbs.py
+++ b/bookwyrm/activitypub/verbs.py
@@ -48,6 +48,10 @@ class Follow(Verb):
     ''' Follow activity '''
     type: str = 'Follow'
 
+@dataclass(init=False)
+class Block(Verb):
+    ''' Block activity '''
+    type: str = 'Block'
 
 @dataclass(init=False)
 class Accept(Verb):
diff --git a/bookwyrm/incoming.py b/bookwyrm/incoming.py
index 9653c5d23..5d93756f5 100644
--- a/bookwyrm/incoming.py
+++ b/bookwyrm/incoming.py
@@ -3,6 +3,7 @@ import json
 from urllib.parse import urldefrag
 
 import django.db.utils
+from django.db.models import Q
 from django.http import HttpResponse
 from django.http import HttpResponseBadRequest, HttpResponseNotFound
 from django.views.decorators.csrf import csrf_exempt
@@ -51,6 +52,7 @@ def shared_inbox(request):
         'Follow': handle_follow,
         'Accept': handle_follow_accept,
         'Reject': handle_follow_reject,
+        'Block': handle_block,
         'Create': handle_create,
         'Delete': handle_delete_status,
         'Like': handle_favorite,
@@ -179,6 +181,22 @@ def handle_follow_reject(activity):
     request.delete()
     #raises models.UserFollowRequest.DoesNotExist
 
+@app.task
+def handle_block(activity):
+    ''' blocking a user '''
+    # create "block" databse entry
+    block = activitypub.Block(**activity).to_model(models.UserBlocks)
+
+    # remove follow relationships
+    models.UserFollows.objects.filter(
+        Q(user_subject=block.user_subject, user_object=block.user_object) | \
+            Q(user_subject=block.user_object, user_object=block.user_subject)
+    ).delete()
+    models.UserFollowRequest.objects.filter(
+        Q(user_subject=block.user_subject, user_object=block.user_object) | \
+            Q(user_subject=block.user_object, user_object=block.user_subject)
+    ).delete()
+
 
 @app.task
 def handle_create(activity):
diff --git a/bookwyrm/models/relationship.py b/bookwyrm/models/relationship.py
index 0f3c1dab9..9ea75a8f7 100644
--- a/bookwyrm/models/relationship.py
+++ b/bookwyrm/models/relationship.py
@@ -94,5 +94,5 @@ class UserFollowRequest(UserRelationship):
 
 class UserBlocks(UserRelationship):
     ''' prevent another user from following you and seeing your posts '''
-    # TODO: not implemented
     status = 'blocks'
+    activity_serializer = activitypub.Block
diff --git a/bookwyrm/tests/test_incoming.py b/bookwyrm/tests/test_incoming.py
index 2cd4869e3..024c8e253 100644
--- a/bookwyrm/tests/test_incoming.py
+++ b/bookwyrm/tests/test_incoming.py
@@ -540,3 +540,29 @@ class Incoming(TestCase):
             incoming.handle_update_work({'object': bookdata})
         book = models.Work.objects.get(id=book.id)
         self.assertEqual(book.title, 'Piranesi')
+
+
+    def test_handle_blocks(self):
+        ''' create a "block" database entry from an activity '''
+        self.local_user.followers.add(self.remote_user)
+        models.UserFollowRequest.objects.create(
+            user_subject=self.local_user,
+            user_object=self.remote_user)
+        self.assertTrue(models.UserFollows.objects.exists())
+        self.assertTrue(models.UserFollowRequest.objects.exists())
+
+        activity = {
+            "@context": "https://www.w3.org/ns/activitystreams",
+            "id": "https://example.com/9e1f41ac-9ddd-4159-aede-9f43c6b9314f",
+            "type": "Block",
+            "actor": "https://example.com/users/rat",
+            "object": "https://example.com/user/mouse"
+        }
+
+        incoming.handle_block(activity)
+        block = models.UserBlocks.objects.get()
+        self.assertEqual(block.user_subject, self.remote_user)
+        self.assertEqual(block.user_object, self.local_user)
+
+        self.assertFalse(models.UserFollows.objects.exists())
+        self.assertFalse(models.UserFollowRequest.objects.exists())