Send email notification on mention

h/emails/__init__.py

@@ -1,3 +1,3 @@
 from h.emails import reply_notification, reset_password, signup
 
-__all__ = ("reply_notification", "reset_password", "signup")
+__all__ = ("mention_notification", "reply_notification", "reset_password", "signup")

h/emails/mention_notification.py

@@ -0,0 +1,30 @@
+from pyramid.renderers import render
+from pyramid.request import Request
+
+from h import links
+from h.emails.util import get_user_url
+from h.notification.mention import Notification
+
+
+def generate(request: Request, notification: Notification):
+    context = {
+        "user_url": get_user_url(notification.mentioning_user, request),
+        "user_display_name": notification.mentioning_user.display_name
+        or notification.mentioning_user.username,
+        "annotation_url": links.incontext_link(request, notification.annotation)
+        or request.route_url("annotation", id=notification.annotation.id),
+        "document_title": notification.document.title
+        or notification.annotation.target_uri,
+        "document_url": notification.annotation.target_uri,
+        "annotation": notification.annotation,
+    }
+
+    subject = f"{context['user_display_name']} has mentioned you in an annotation"
+    text = render(
+        "h:templates/emails/mention_notification.txt.jinja2", context, request=request
+    )
+    html = render(
+        "h:templates/emails/mention_notification.html.jinja2", context, request=request
+    )
+
+    return [notification.mentioned_user.email], subject, text, html

h/emails/reply_notification.py

@@ -2,6 +2,7 @@
 from pyramid.request import Request
 
 from h import links
+from h.emails.util import get_user_url
 from h.models import Subscriptions
 from h.notification.reply import Notification
 from h.services import SubscriptionService
@@ -27,7 +28,7 @@ def generate(request: Request, notification: Notification):
         "parent": notification.parent,
         "parent_user_display_name": notification.parent_user.display_name
         or notification.parent_user.username,
-        "parent_user_url": _get_user_url(notification.parent_user, request),
+        "parent_user_url": get_user_url(notification.parent_user, request),
         "unsubscribe_url": request.route_url(
             "unsubscribe",
             token=unsubscribe_token,
@@ -38,7 +39,7 @@ def generate(request: Request, notification: Notification):
         or request.route_url("annotation", id=notification.reply.id),
         "reply_user_display_name": notification.reply_user.display_name
         or notification.reply_user.username,
-        "reply_user_url": _get_user_url(notification.reply_user, request),
+        "reply_user_url": get_user_url(notification.reply_user, request),
     }
 
     subject = f"{context['reply_user_display_name']} has replied to your annotation"
@@ -50,10 +51,3 @@ def generate(request: Request, notification: Notification):
     )
 
     return [notification.parent_user.email], subject, text, html
-
-
-def _get_user_url(user, request):
-    if user.authority == request.default_authority:
-        return request.route_url("stream.user_query", user=user.username)
-
-    return None

h/emails/util.py

@@ -0,0 +1,10 @@
+from pyramid.request import Request
+
+from h.models import User
+
+
+def get_user_url(user: User, request: Request) -> str | None:
+    if user.authority == request.default_authority:
+        return request.route_url("stream.user_query", user=user.username)
+
+    return None

h/notification/mention.py

@@ -0,0 +1,61 @@
+import logging
+from dataclasses import dataclass
+
+from h.models import Annotation, Document, User
+
+logger = logging.getLogger(__name__)
+
+
+@dataclass
+class Notification:
+    """A data structure representing a mention notification in an annotation."""
+
+    mentioning_user: User
+    mentioned_user: User
+    annotation: Annotation
+    document: Document
+
+
+def get_notifications(request, annotation: Annotation, action) -> list[Notification]:
+    # Only send notifications when new annotations are created
+    if action != "create":
+        return []
+
+    user_service = request.find_service(name="user")
+
+    # If the mentioning user doesn't exist (anymore), we can't send emails, but
+    # this would be super weird, so log a warning.
+    mentioning_user = user_service.fetch(annotation.userid)
+    if mentioning_user is None:
+        logger.warning(
+            "user who just mentioned another user no longer exists: %s",
+            annotation.userid,
+        )
+        return []
+
+    notifications = []
+    for mention in annotation.mentions:
+        # If the mentioning user doesn't exist (anymore), we can't send emails
+        mentioned_user = user_service.fetch(mention.user.userid)
+        if mentioned_user is None:
+            continue
+
+        # If mentioned user doesn't have an email address we can't email them.
+        if not mention.user.email:
+            continue
+
+        # Do not notify users about their own replies
+        if mentioning_user == mentioned_user:
+            continue
+
+        # If the annotation doesn't have a document, we can't send an email.
+        if annotation.document is None:
+            continue
+
+        notifications.append(
+            Notification(
+                mentioning_user, mentioned_user, annotation, annotation.document
+            )
+        )
+
+    return notifications

h/subscribers.py

@@ -5,7 +5,7 @@
 from h import __version__, emails
 from h.events import AnnotationEvent
 from h.exceptions import RealtimeMessageQueueError
-from h.notification import reply
+from h.notification import mention, reply
 from h.services.annotation_read import AnnotationReadService
 from h.tasks import mailer
 
@@ -89,3 +89,28 @@ def send_reply_notifications(event):
         except OperationalError as err:  # pragma: no cover
             # We could not connect to rabbit! So carry on
             report_exception(err)
+
+
+@subscriber(AnnotationEvent)
+def send_mention_notifications(event):
+    """Send mention notifications triggered by a mention event."""
+
+    request = event.request
+
+    with request.tm:
+        annotation = request.find_service(AnnotationReadService).get_annotation_by_id(
+            event.annotation_id,
+        )
+        notifications = mention.get_notifications(request, annotation, event.action)
+
+        if not notifications:
+            return
+
+        for notification in notifications:
+            send_params = emails.mention_notification.generate(request, notification)
+
+            try:
+                mailer.send.delay(*send_params)
+            except OperationalError as err:  # pragma: no cover
+                # We could not connect to rabbit! So carry on
+                report_exception(err)

h/templates/emails/mention_notification.html.jinja2

@@ -0,0 +1,26 @@
+<p>
+  {% if user_url %}
+    <a href="{{ user_url }}">{{ user_display_name }}</a>
+  {% else %}
+    {{ user_display_name }}
+  {% endif %}
+  has
+  <a href="{{ annotation_url }}">mentioned you</a>
+  on
+  <a href="{{ document_url }}">&ldquo;{{ document_title }}&rdquo;</a>:
+</p>
+
+<p>
+  On
+  {{ annotation.updated | human_timestamp }}
+  {% if user_url %}
+    <a href="{{ user_url }}">{{ user_display_name }}</a>
+  {% else %}
+    {{ user_display_name }}
+  {% endif %}
+  commented:
+</p>
+
+<blockquote>{{ (annotation.text or "")|striptags }}</blockquote>
+
+<p><a href="{{ annotation_url }}">View the thread and respond</a>.</p>

h/templates/emails/mention_notification.txt.jinja2

@@ -0,0 +1,7 @@
+{{ user_display_name }} has replied to your annotation on "{{ document_title }}":
+
+On {{ annotation.updated | human_timestamp }} {{ user_display_name }} replied:
+
+> {{ (annotation.text or "")|striptags }}
+
+View the thread and respond: {{ annotation_url }}

h/templates/emails/reply_notification.html.jinja2

@@ -21,7 +21,7 @@
   commented:
 </p>
 
-<blockquote>{{ parent.text or "" }}</blockquote>
+<blockquote>{{ (parent.text or "")|striptags }}</blockquote>
 
 <p>
   On
@@ -34,7 +34,7 @@
   replied:
 </p>
 
-<blockquote>{{ reply.text or "" }}</blockquote>
+<blockquote>{{ (reply.text or "")|striptags }}</blockquote>
 
 <p><a href="{{ reply_url }}">View the thread and respond</a>.</p>
 

h/templates/emails/reply_notification.txt.jinja2

@@ -2,11 +2,11 @@
 
 On {{ parent.created | human_timestamp }} {{ parent_user_display_name }} commented:
 
-> {{ parent.text or "" }}
+> {{ (parent.text or "")|striptags }}
 
 On {{ reply.created | human_timestamp }} {{ reply_user_display_name }} replied:
 
-> {{ reply.text or "" }}
+> {{ (reply.text or "")|striptags }}
 
 View the thread and respond: {{ reply_url }}