Add Move activity for user migration

bookwyrm/activitypub/__init__.py

@@ -19,6 +19,7 @@
 from .verbs import Follow, Accept, Reject, Block
 from .verbs import Add, Remove
 from .verbs import Announce, Like
+from .verbs import Move
 
 # this creates a list of all the Activity types that we can serialize,
 # so when an Activity comes in from outside, we can check if it's known

bookwyrm/activitypub/verbs.py

@@ -231,3 +231,28 @@ class Announce(Verb):
     def action(self, allow_external_connections=True):
         """boost"""
         self.to_model(allow_external_connections=allow_external_connections)
+
+@dataclass(init=False)
+class Move(Verb):
+    """a user moving an object"""
+
+    # note the spec example for target and origin is an object but
+    # Mastodon uses a URI string and TBH this makes more sense
+    # Is there a way we can account for either format?
+
+    object: str
+    type: str = "Move"
+    target: str
+    origin: str
+
+    def action(self, allow_external_connections=True):
+        """move"""
+
+        # we need to work out whether the object is a user or something else.
+
+        object_is_user = True # TODO!
+
+        if object_is_user:
+            self.to_model(object_is_user=True allow_external_connections=allow_external_connections)
+        else:
+            self.to_model(object_is_user=False allow_external_connections=allow_external_connections)

bookwyrm/models/move.py

@@ -0,0 +1,50 @@
+""" move an object including migrating a user account """
+from django.db import models
+
+from bookwyrm import activitypub
+from .activitypub_mixin import ActivityMixin
+from .base_model import BookWyrmModel
+from . import fields
+from .status import Status
+
+
+class Move(ActivityMixin, BookWyrmModel):
+    """migrating an activitypub user account"""
+
+    user = fields.ForeignKey(
+        "User", on_delete=models.PROTECT, activitypub_field="actor"
+    )
+
+    # TODO: can we just use the abstract class here?
+    activitypub_object = fields.ForeignKey(
+        "BookWyrmModel", on_delete=models.PROTECT,
+        activitypub_field="object",
+        blank=True,
+        null=True
+    )
+
+    target = fields.CharField(
+        max_length=255, blank=True, null=True, deduplication_field=True
+    )
+
+    origin = fields.CharField(
+        max_length=255, blank=True, null=True, deduplication_field=True
+    )
+
+    activity_serializer = activitypub.Move
+
+    # pylint: disable=unused-argument
+    @classmethod
+    def ignore_activity(cls, activity, allow_external_connections=True):
+        """don't bother with incoming moves of unknown objects"""
+        # TODO how do we check this for any conceivable object?
+        pass
+
+    def save(self, *args, **kwargs):
+        """update user active time"""
+        self.user.update_active_date()
+        super().save(*args, **kwargs)
+
+    # Ok what else? We can trigger a notification for followers of a user who sends a `Move` for themselves
+    # What about when a book is merged (i.e. moved from one id into another)? We could use that to send out a message
+    # to other Bookwyrm instances to update their remote_id for the book, but ...how do we trigger any action?

bookwyrm/models/notification.py

@@ -40,11 +40,14 @@ class Notification(BookWyrmModel):
     GROUP_NAME = "GROUP_NAME"
     GROUP_DESCRIPTION = "GROUP_DESCRIPTION"
 
+    # Migrations
+    MOVE = "MOVE"
+
     # pylint: disable=line-too-long
     NotificationType = models.TextChoices(
         # there has got be a better way to do this
         "NotificationType",
-        f"{FAVORITE} {REPLY} {MENTION} {TAG} {FOLLOW} {FOLLOW_REQUEST} {BOOST} {IMPORT} {ADD} {REPORT} {LINK_DOMAIN} {INVITE} {ACCEPT} {JOIN} {LEAVE} {REMOVE} {GROUP_PRIVACY} {GROUP_NAME} {GROUP_DESCRIPTION}",
+        f"{FAVORITE} {REPLY} {MENTION} {TAG} {FOLLOW} {FOLLOW_REQUEST} {BOOST} {IMPORT} {ADD} {REPORT} {LINK_DOMAIN} {INVITE} {ACCEPT} {JOIN} {LEAVE} {REMOVE} {GROUP_PRIVACY} {GROUP_NAME} {GROUP_DESCRIPTION} {MOVE}",
     )
 
     user = models.ForeignKey("User", on_delete=models.CASCADE)
@@ -326,3 +329,14 @@ def notify_user_on_follow(sender, instance, created, *args, **kwargs):
             notification_type=Notification.FOLLOW,
             read=False,
         )
+
+@receiver(models.signals.post_save, sender=Move)
+# pylint: disable=unused-argument
+def notify_on_move(sender, instance, *args, **kwargs):
+    """someone moved something"""
+    Notification.notify(
+        instance.status.user,
+        instance.user,
+        related_object=instance.object,
+        notification_type=Notification.MOVE,
+    )

bookwyrm/templates/notifications/item.html

@@ -35,4 +35,6 @@
     {% include 'notifications/items/update.html' %}
 {% elif notification.notification_type == 'GROUP_DESCRIPTION' %}
     {% include 'notifications/items/update.html' %}
+    {% elif notification.notification_type == 'MOVE' %}
+    {% include 'notifications/items/move.html' %}
 {% endif %}

bookwyrm/templates/notifications/items/move.html

@@ -0,0 +1,28 @@
+{% extends 'notifications/items/layout.html' %}
+
+{% load i18n %}
+{% load utilities %}
+
+{% block primary_link %}{% spaceless %}
+    {{ notification.related_object.local_path }}
+{% endspaceless %}{% endblock %}
+
+{% block icon %}
+    <span class="icon icon-local"></span>
+{% endblock %}
+
+{% block description %}
+    <!--
+        TODO: a user has a 'name' but not everything does, notably a book.
+        On the other hand, maybe we don't need to notify anyone if a book
+        is moved, just update the remote_id?
+    -->
+    {% blocktrans trimmed with object_name=notification.related_object.name object_path=notification.related_object.local_path %}
+    <a href="{{ related_user_link }}">{{ related_user }}</a>
+    moved {{ object_name }}
+    "<a href="{{ object_path }}">{{ object_name }}</a>"
+    {% endblocktrans %}
+
+    <!-- TODO maybe put a brief context message here for migrated user accounts? -->
+
+{% endblock %}