Message service backend setup: switch config form per-service in the UI

See #281, which this commit prepares for

alerts/forms.py

@@ -3,7 +3,7 @@ from django.forms import ModelForm
 from .models import MessagingServiceConfig
 
 
-class MessagingServiceConfigForm(ModelForm):
+class MessagingServiceConfigNewForm(ModelForm):
 
     def __init__(self, project, *args, **kwargs):
         super().__init__(*args, **kwargs)
@@ -19,3 +19,13 @@ class MessagingServiceConfigForm(ModelForm):
         if commit:
             instance.save()
         return instance
+
+
+class MessagingServiceConfigEditForm(ModelForm):
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+
+    class Meta:
+        model = MessagingServiceConfig
+        fields = ["display_name"]

alerts/migrations/0004_alter_messagingserviceconfig_kind.py

@@ -14,7 +14,7 @@ class Migration(migrations.Migration):
             model_name="messagingserviceconfig",
             name="kind",
             field=models.CharField(
-                choices=alerts.models.kind_choices, default="slack", max_length=20
+                choices=alerts.models.get_alert_service_kind_choices, default="slack", max_length=20
             ),
         ),
     ]

alerts/models.py

@@ -6,7 +6,7 @@ from .service_backends.mattermost import MattermostBackend
 from .service_backends.discord import DiscordBackend
 
 
-def kind_choices():
+def get_alert_service_kind_choices():
     # As a callable to avoid non-DB-affecting migrations for adding new kinds.
     # Messaging backends don't need translations since they are brand names.
     return [
@@ -16,12 +16,22 @@ def kind_choices():
     ]
 
 
+def get_alert_service_backend_class(kind):
+    if kind == "discord":
+        return DiscordBackend
+    if kind == "mattermost":
+        return MattermostBackend
+    if kind == "slack":
+        return SlackBackend
+    raise ValueError(f"Unknown backend kind: {kind}")
+
+
 class MessagingServiceConfig(models.Model):
     project = models.ForeignKey(Project, on_delete=models.DO_NOTHING, related_name="service_configs")
     display_name = models.CharField(max_length=100, blank=False,
                                     help_text='For display in the UI, e.g. "#general on company Slack"')
 
-    kind = models.CharField(choices=kind_choices, max_length=20, default="slack")
+    kind = models.CharField(choices=get_alert_service_kind_choices, max_length=20, default="slack")
 
     config = models.TextField(blank=False)
 
@@ -40,13 +50,7 @@ class MessagingServiceConfig(models.Model):
                                                   help_text="Error message from the exception")
 
     def get_backend(self):
-        if self.kind == "discord":
-            return DiscordBackend(self)
-        if self.kind == "mattermost":
-            return MattermostBackend(self)
-        if self.kind == "slack":
-            return SlackBackend(self)
-        raise ValueError(f"Unknown backend kind: {self.kind}")
+        return get_alert_service_backend_class(self.kind)(self)
 
     def clear_failure_status(self):
         """Clear all failure tracking fields on successful operation"""

alerts/service_backends/discord.py

@@ -203,7 +203,8 @@ class DiscordBackend:
     def __init__(self, service_config):
         self.service_config = service_config
 
-    def get_form_class(self):
+    @classmethod
+    def get_form_class(cls):
         return DiscordConfigForm
 
     def send_test_message(self):

alerts/service_backends/mattermost.py

@@ -185,7 +185,8 @@ class MattermostBackend:
     def __init__(self, service_config):
         self.service_config = service_config
 
-    def get_form_class(self):
+    @classmethod
+    def get_form_class(cls):
         return MattermostConfigForm
 
     def send_test_message(self):

alerts/service_backends/slack.py

@@ -222,7 +222,8 @@ class SlackBackend:
     def __init__(self, service_config):
         self.service_config = service_config
 
-    def get_form_class(self):
+    @classmethod
+    def get_form_class(cls):
         return SlackConfigForm
 
     def send_test_message(self):

projects/templates/projects/project_messaging_service_new.html

@@ -0,0 +1,79 @@
+{% extends "base.html" %}
+{% load static %}
+{% load tailwind_forms %}
+
+{% block title %}Messaging Service · {{ project.name }}  · {{ site_title }}{% endblock %}
+
+{% block content %}
+
+<div class="flex items-center justify-center">
+
+    <div class="m-4 max-w-4xl flex-auto">
+        <form action="." method="post">
+        {% csrf_token %}
+
+        {% if messages %}
+        <ul>
+            {% for message in messages %}
+                {# if we introduce different levels we can use{% message.level == DEFAULT_MESSAGE_LEVELS.SUCCESS %} #}
+                <li class="bg-cyan-50 dark:bg-cyan-900 border-2 border-cyan-800 dark:border-cyan-400 p-4 rounded-lg">{{ message }}</li>
+            {% endfor %}
+        </ul>
+        {% endif %}
+
+        <div>
+            <h1 class="text-4xl my-4 font-bold">Messaging Service | {{ project.name }}</h1>
+        </div>
+
+        {% for field in form %}
+            {% tailwind_formfield field %}
+        {% endfor %}
+
+        {% for config_form_kind, config_form in config_forms.items %}
+            <div
+                class="config-form-block {% if config_form_kind == selected_config_form_kind %}block{% else %}hidden{% endif %}" data-config-kind="{{ config_form_kind }}">
+
+                {% for field in config_form %}
+                    {% tailwind_formfield field %}
+                {% endfor %}
+            </div>
+        {% endfor %}
+
+
+        <button name="action" value="add" class="font-bold text-slate-800 dark:text-slate-100 border-slate-500 dark:border-slate-400 pl-4 pr-4 pb-2 pt-2 border-2 bg-cyan-200 dark:bg-cyan-700 hover:bg-cyan-400 dark:hover:bg-cyan-600 active:ring-3 rounded-md">Save</button>
+        <a href="{% url "project_alerts_setup" project_pk=project.pk %}" class="font-bold text-slate-500 dark:text-slate-300 ml-4">Cancel</a>
+
+        </form>
+
+    </div>
+</div>
+
+{% endblock %}
+
+{% block extra_js %}
+<script>
+document.addEventListener('DOMContentLoaded', function () {
+    const kindSelect = document.querySelector('select[name="kind"]');
+    const blocks = document.querySelectorAll('.config-form-block');
+
+    function updateConfigForms() {
+        const selectedKind = kindSelect.value;
+
+        blocks.forEach(block => {
+            const blockKind = block.dataset.configKind;
+            const isActive = (blockKind === selectedKind);
+
+            block.classList.toggle('hidden', !isActive);
+            block.classList.toggle('block', isActive);
+            block.querySelectorAll('input, select, textarea, button').forEach(element => {
+                element.disabled = !isActive;
+            });
+        });
+    }
+
+    updateConfigForms();  // Initialize on page load
+
+    kindSelect.addEventListener('change', updateConfigForms);
+});
+</script>
+{% endblock %}

projects/views.py

@@ -20,9 +20,8 @@ from bugsink.app_settings import get_settings, CB_ANYBODY, CB_MEMBERS, CB_ADMINS
 from bugsink.decorators import login_exempt, atomic_for_request_method
 from bugsink.utils import assert_
 
-from alerts.models import MessagingServiceConfig
-from alerts.forms import MessagingServiceConfigForm
-from alerts.service_backends.slack import SlackConfigForm
+from alerts.models import MessagingServiceConfig, get_alert_service_backend_class, get_alert_service_kind_choices
+from alerts.forms import MessagingServiceConfigNewForm, MessagingServiceConfigEditForm
 
 from .models import Project, ProjectMembership, ProjectRole, ProjectVisibility
 from .forms import ProjectMembershipForm, MyProjectMembershipForm, ProjectMemberInviteForm, ProjectForm
@@ -457,26 +456,35 @@ def project_messaging_service_add(request, project_pk):
     project = Project.objects.get(id=project_pk, is_deleted=False)
     _check_project_admin(project, request.user)
 
+    config_forms = {
+        kind: get_alert_service_backend_class(kind).get_form_class()()
+        for (kind, _) in get_alert_service_kind_choices()
+    }
+
     if request.method == 'POST':
-        form = MessagingServiceConfigForm(project, request.POST)
-        config_form = SlackConfigForm(data=request.POST)
+        form = MessagingServiceConfigNewForm(project, request.POST)
+        kind = form.data.get('kind') or form.fields['kind'].initial
+        config_form = get_alert_service_backend_class(kind).get_form_class()(data=request.POST)
+        config_forms[kind] = config_form
 
-        if form.is_valid() and config_form.is_valid():
-            service = form.save(commit=False)
-            service.config = json.dumps(config_form.get_config())
-            service.save()
+        if form.is_valid():
+            if config_form.is_valid():
+                service = form.save(commit=False)
+                service.config = json.dumps(config_form.get_config())
+                service.save()
 
-            messages.success(request, "Messaging service added successfully.")
-            return redirect('project_alerts_setup', project_pk=project_pk)
+                messages.success(request, "Messaging service added successfully.")
+                return redirect('project_alerts_setup', project_pk=project_pk)
 
     else:
-        form = MessagingServiceConfigForm(project)
-        config_form = SlackConfigForm()
+        form = MessagingServiceConfigNewForm(project)
+        kind = form.fields['kind'].initial
 
-    return render(request, 'projects/project_messaging_service_edit.html', {
+    return render(request, 'projects/project_messaging_service_new.html', {
         'project': project,
         'form': form,
-        'config_form': config_form,
+        'config_forms': config_forms,
+        'selected_config_form_kind': kind,
     })
 
 
@@ -486,10 +494,14 @@ def project_messaging_service_edit(request, project_pk, service_pk):
     _check_project_admin(project, request.user)
 
     instance = project.service_configs.get(id=service_pk)
+    # for editing, we don't allow for changing the kind; although it's probably possible to implement it, it would raise
+    # questions on "how much are the various configs related (should data be transferred from one config to another).
+    # and even though "it's possible" simply disallowing greatly simplifies the implementation.
+    config_form_class = get_alert_service_backend_class(instance.kind).get_form_class()
 
     if request.method == 'POST':
-        form = MessagingServiceConfigForm(project, request.POST, instance=instance)
-        config_form = SlackConfigForm(data=request.POST)
+        form = MessagingServiceConfigEditForm(request.POST, instance=instance)
+        config_form = config_form_class(data=request.POST)
 
         if form.is_valid() and config_form.is_valid():
             service = form.save(commit=False)
@@ -500,8 +512,8 @@ def project_messaging_service_edit(request, project_pk, service_pk):
             return redirect('project_alerts_setup', project_pk=project_pk)
 
     else:
-        form = MessagingServiceConfigForm(project, instance=instance)
-        config_form = SlackConfigForm(config=json.loads(instance.config))
+        form = MessagingServiceConfigEditForm(instance=instance)
+        config_form = config_form_class(config=json.loads(instance.config))
 
     return render(request, 'projects/project_messaging_service_edit.html', {
         'project': project,