Add Direct Messages (#3093)

This PR adds the Direct Messages application. It introduces three main
new models:

- `Conversation`: Many users are `participants` of one conversation.
Many permissions are added to each conversation - view,
create_conversation_direct_message, mark_conversation_read,
mark_conversation_message_as_spam.
- `DirectMessage`: Has a foreign key to a `conversation`, `sender` and
which users have not read this message. The sender can delete the
message and the conversation participants can mark the message as spam.
If a direct message is created the other participants in the group have
the message marked as unread. If a message is deleted or marked as spam
then all of the unread markers are deleted.
- `Mute`: tracks which users have muted which other users. If a direct
message is created and the receiver has muted the sender the message is
not marked as unread by the receiver.

The views use HTMX. As a conversation is loaded all of the messages are
marked as read as a callback. For now only challenge admins can message
their participants.

See DIAGNijmegen/rse-roadmap#255

app/config/settings.py

@@ -598,6 +598,7 @@
     "grandchallenge.charts",
     "grandchallenge.forums",
     "grandchallenge.invoices",
+    "grandchallenge.direct_messages",
 ]
 
 INSTALLED_APPS = DJANGO_APPS + LOCAL_APPS + THIRD_PARTY_APPS

app/config/urls/root.py

@@ -175,6 +175,12 @@ def handler500(request):
         "components/",
         include("grandchallenge.components.urls", namespace="components"),
     ),
+    path(
+        "messages/",
+        include(
+            "grandchallenge.direct_messages.urls", namespace="direct-messages"
+        ),
+    ),
 ]
 
 if settings.DEBUG and settings.ENABLE_DEBUG_TOOLBAR:

app/grandchallenge/core/templates/grandchallenge/partials/userlinks.html

@@ -42,19 +42,31 @@ <h6 class="dropdown-header">{{ request.site.name }} Support</h6>
     </div>
 </li>
 {% if user.is_authenticated %}
-    {% if ACTSTREAM_ENABLE %}
     <li class="nav-item mr-auto">
-        {% if user.user_profile.has_unread_notifications %}
+        {% if user.directmessageunreadby_set.exists %}
             <span class="text-danger float-right mb-n3">
                 <i class="fa fa-xs fa-circle"></i>
             </span>
         {% endif %}
         <a class="nav-link pr-1"
-           href="{% url 'notifications:list' %}"
-           title="Notifications">
-            <i class="align-middle far fa-fw fa-lg fa-bell"></i>
+           href="{% url 'direct-messages:conversation-list' %}"
+           title="Conversations">
+            <i class="align-middle far fa-fw fa-lg fa-comment"></i>
         </a>
     </li>
+    {% if ACTSTREAM_ENABLE %}
+        <li class="nav-item mr-auto">
+            {% if user.user_profile.has_unread_notifications %}
+                <span class="text-danger float-right mb-n3">
+                    <i class="fa fa-xs fa-circle"></i>
+                </span>
+            {% endif %}
+            <a class="nav-link pr-1"
+               href="{% url 'notifications:list' %}"
+               title="Notifications">
+                <i class="align-middle far fa-fw fa-lg fa-bell"></i>
+            </a>
+        </li>
     {% endif %}
     <li class="nav-item dropdown">
         <a href="#" class="nav-link dropdown-toggle align-top"

app/grandchallenge/direct_messages/admin.py

@@ -0,0 +1,75 @@
+from django.contrib import admin
+
+from grandchallenge.direct_messages.models import (
+    Conversation,
+    DirectMessage,
+    Mute,
+)
+
+
+@admin.register(Conversation)
+class ConversationAdmin(admin.ModelAdmin):
+    list_display = (
+        "pk",
+        "participant_usernames",
+    )
+    list_prefetch_related = ("participants",)
+    readonly_fields = ("participant_usernames",)
+    search_fields = (
+        "pk",
+        "participants__username",
+    )
+
+    def participant_usernames(self, obj):
+        return ", ".join(user.username for user in obj.participants.all())
+
+
+@admin.register(DirectMessage)
+class DirectMessageAdmin(admin.ModelAdmin):
+    list_display = (
+        "pk",
+        "created",
+        "sender",
+        "unread_by_usernames",
+        "is_reported_as_spam",
+        "is_deleted",
+        "message",
+    )
+    readonly_fields = (
+        "conversation",
+        "sender",
+        "message",
+        "unread_by_usernames",
+    )
+    list_filter = (
+        "is_reported_as_spam",
+        "is_deleted",
+    )
+    list_prefetch_related = ("unread_by",)
+    ordering = ("-created",)
+    search_fields = (
+        "pk",
+        "sender__username",
+        "conversation__pk",
+        "unread_by__username",
+    )
+
+    def unread_by_usernames(self, obj):
+        return ", ".join(user.username for user in obj.unread_by.all())
+
+
+@admin.register(Mute)
+class MuteAdmin(admin.ModelAdmin):
+    list_display = (
+        "pk",
+        "source",
+        "target",
+    )
+    readonly_fields = (
+        "source",
+        "target",
+    )
+    search_fields = (
+        "source__username",
+        "target__username",
+    )

app/grandchallenge/direct_messages/apps.py

@@ -0,0 +1,9 @@
+from django.apps import AppConfig
+
+
+class DirectMessagesConfig(AppConfig):
+    name = "grandchallenge.direct_messages"
+
+    def ready(self):
+        # noinspection PyUnresolvedReferences
+        import grandchallenge.direct_messages.signals  # noqa: F401

app/grandchallenge/direct_messages/forms.py

@@ -0,0 +1,188 @@
+from crispy_forms.bootstrap import StrictButton
+from crispy_forms.helper import FormHelper
+from crispy_forms.layout import Submit
+from django import forms
+from django.contrib.auth import get_user_model
+from django.core.exceptions import ValidationError
+from guardian.utils import get_anonymous_user
+
+from grandchallenge.core.guardian import filter_by_permission
+from grandchallenge.direct_messages.models import (
+    Conversation,
+    DirectMessage,
+    Mute,
+)
+
+
+class ConversationForm(forms.ModelForm):
+    def __init__(self, *args, participants, **kwargs):
+        super().__init__(*args, **kwargs)
+
+        self.helper = FormHelper(self)
+        self.helper.layout.append(
+            StrictButton(
+                '<i class="far fa-comment"></i> Message User',
+                type="submit",
+                css_class="btn btn-primary",
+            )
+        )
+
+        self.fields["participants"].queryset = participants
+        self.fields["participants"].initial = participants
+        self.fields["participants"].disabled = True
+        self.fields["participants"].widget = forms.MultipleHiddenInput()
+
+    def clean_participants(self):
+        participants = self.cleaned_data["participants"]
+
+        if get_anonymous_user() in participants:
+            raise ValidationError("You cannot add this user!")
+
+        if len(participants) < 2:
+            raise ValidationError("Too few participants")
+
+        if existing := Conversation.objects.for_participants(
+            participants=participants
+        ):
+            self.existing_conversations = existing
+            raise ValidationError(
+                "Conversation already exists", code="CONVERSATION_EXISTS"
+            )
+
+        return participants
+
+    class Meta:
+        model = Conversation
+        fields = ("participants",)
+
+
+class DirectMessageForm(forms.ModelForm):
+    def __init__(self, *args, conversation, sender, **kwargs):
+        super().__init__(*args, **kwargs)
+
+        self.helper = FormHelper(self)
+        self.helper.layout.append(Submit("save", "Send"))
+
+        self.fields["conversation"].queryset = filter_by_permission(
+            queryset=Conversation.objects.filter(pk=conversation.pk),
+            user=sender,
+            codename="create_conversation_direct_message",
+        )
+        self.fields["conversation"].initial = conversation
+        self.fields["conversation"].disabled = True
+        self.fields["conversation"].widget = forms.HiddenInput()
+
+        self.fields["sender"].queryset = get_user_model().objects.filter(
+            pk=sender.pk
+        )
+        self.fields["sender"].initial = sender
+        self.fields["sender"].disabled = True
+        self.fields["sender"].widget = forms.HiddenInput()
+
+        exclude_notifications = {
+            m.source.pk
+            for m in Mute.objects.filter(
+                target=sender, source__in=conversation.participants.all()
+            )
+        }
+        exclude_notifications.add(sender.pk)
+        unread_by = conversation.participants.exclude(
+            pk__in=exclude_notifications
+        )
+
+        self.fields["unread_by"].queryset = unread_by
+        self.fields["unread_by"].initial = unread_by
+        self.fields["unread_by"].disabled = True
+        self.fields["unread_by"].widget = forms.MultipleHiddenInput()
+        self.fields["unread_by"].required = False
+
+        self.fields["message"].widget = forms.Textarea(
+            attrs={
+                "placeholder": "Write a message...",
+                "rows": "3",
+                "style": "resize:none;",
+            }
+        )
+        self.fields["message"].label = ""
+
+    class Meta:
+        model = DirectMessage
+        fields = (
+            "conversation",
+            "sender",
+            "unread_by",
+            "message",
+        )
+
+
+class DirectMessageReportSpamForm(forms.ModelForm):
+    is_reported_as_spam = forms.BooleanField(
+        initial=True, required=True, widget=forms.HiddenInput
+    )
+
+    class Meta:
+        model = DirectMessage
+        fields = ("is_reported_as_spam",)
+
+
+class MuteForm(forms.ModelForm):
+    conversation = forms.ModelChoiceField(
+        queryset=Conversation.objects.none(), widget=forms.HiddenInput()
+    )
+
+    def __init__(self, *args, source, target, **kwargs):
+        super().__init__(*args, **kwargs)
+
+        self.fields["source"].queryset = get_user_model().objects.filter(
+            pk=source.pk
+        )
+        self.fields["source"].initial = source
+        self.fields["source"].disabled = True
+        self.fields["source"].widget = forms.HiddenInput()
+
+        self.fields["target"].queryset = get_user_model().objects.filter(
+            pk=target.pk
+        )
+        self.fields["target"].initial = target
+        self.fields["target"].disabled = True
+        self.fields["target"].widget = forms.HiddenInput()
+
+        self.fields["conversation"].queryset = filter_by_permission(
+            queryset=Conversation.objects.all(),
+            user=source,
+            codename="view_conversation",
+        )
+
+    def clean(self):
+        cleaned_data = super().clean()
+
+        if cleaned_data["source"] == cleaned_data["target"]:
+            raise ValidationError("You cannot mute yourself")
+
+        return cleaned_data
+
+    class Meta:
+        model = Mute
+        fields = (
+            "source",
+            "target",
+        )
+
+
+class MuteDeleteForm(forms.ModelForm):
+    conversation = forms.ModelChoiceField(
+        queryset=Conversation.objects.none(), widget=forms.HiddenInput()
+    )
+
+    def __init__(self, *args, user, **kwargs):
+        super().__init__(*args, **kwargs)
+
+        self.fields["conversation"].queryset = filter_by_permission(
+            queryset=Conversation.objects.all(),
+            user=user,
+            codename="view_conversation",
+        )
+
+    class Meta:
+        model = Mute
+        fields = ()