feat: add logging app

apis_core/logging/apps.py

@@ -0,0 +1,9 @@
+from django.apps import AppConfig
+
+
+class LoggingConfig(AppConfig):
+    default_auto_field = "django.db.models.AutoField"
+    name = "apis_core.logging"
+
+    def ready(self):
+        from . import signals

apis_core/logging/migrations/0001_initial.py

@@ -0,0 +1,47 @@
+# Generated by Django 4.2.9 on 2024-01-26 08:14
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    initial = True
+
+    dependencies = [
+        ("contenttypes", "0002_remove_content_type_name"),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name="CustomLogEntry",
+            fields=[
+                (
+                    "id",
+                    models.AutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                ("user", models.CharField(editable=False, max_length=150)),
+                ("action_time", models.DateTimeField(auto_now_add=True)),
+                ("object_id", models.PositiveIntegerField(blank=True, null=True)),
+                ("message", models.TextField(null=True)),
+                ("metadata", models.JSONField(null=True)),
+                (
+                    "content_type",
+                    models.ForeignKey(
+                        blank=True,
+                        null=True,
+                        on_delete=django.db.models.deletion.CASCADE,
+                        to="contenttypes.contenttype",
+                    ),
+                ),
+            ],
+            options={
+                "ordering": ["-action_time"],
+            },
+        ),
+    ]

apis_core/logging/models.py

@@ -0,0 +1,65 @@
+from django.contrib.contenttypes.fields import GenericForeignKey
+from django.contrib.contenttypes.models import ContentType
+from django.db import models
+
+
+class CustomLogEntryManager(models.Manager):
+    def log_action(self, user, obj=None, message="", metadata={}):
+        username = "System action"
+        if user:
+            username = str(user)
+        entry = self.model.objects.create(user=username)
+        if obj:
+            content_type = ContentType.objects.get_for_model(obj)
+            entry.content_type = content_type
+            natural_key = f"{content_type.app_label}.{content_type.name}"
+            metadata["natural_key"] = natural_key
+            message += f" {natural_key}: {obj}"
+            metadata["pk"] = obj.pk
+            if hasattr(obj, "id"):
+                entry.object_id = obj.id
+        if message:
+            entry.message = message
+        if metadata:
+            entry.metadata = metadata
+        entry.save()
+
+    def add_something(self, user, obj):
+        message = f"{user} added"
+        metadata = {"type": "add"}
+        self.log_action(user, obj, message, metadata)
+
+    def delete_something(self, user, obj):
+        message = f"{user} deleted"
+        metadata = {"type": "del"}
+        self.log_action(user, obj, message, metadata)
+
+    def change_something(self, user, obj, update_fields=[]):
+        message = f"{user} changed"
+        metadata = {"type": "change", "update_fields": update_fields}
+        self.log_action(user, obj, message, metadata)
+
+
+class CustomLogEntry(models.Model):
+    """
+    A custom LogEntry model. Django has its own contrib.admin.LogEntry, but that
+    is primarily used for actions in the admin area. Using a custom LogEntry we
+    are more flexible.
+    """
+
+    user = models.CharField(max_length=150, editable=False)
+    action_time = models.DateTimeField(auto_now_add=True, editable=False)
+
+    content_type = models.ForeignKey(
+        ContentType, on_delete=models.CASCADE, blank=True, null=True
+    )
+    object_id = models.PositiveIntegerField(blank=True, null=True)
+    content_object = GenericForeignKey("content_type", "object_id")
+
+    message = models.TextField(null=True)
+    metadata = models.JSONField(null=True)
+
+    objects = CustomLogEntryManager()
+
+    class Meta:
+        ordering = ["-action_time"]

apis_core/logging/signals.py

@@ -0,0 +1,32 @@
+from django.db.models.signals import post_save, post_delete
+from django.dispatch import receiver
+from crum import get_current_request
+
+from .models import CustomLogEntry
+
+
+@receiver(post_save)
+def log_save(sender, instance, created, raw, using, update_fields, **kwargs):
+    if sender is CustomLogEntry:
+        return
+    user = None
+    request = get_current_request()
+    if request:
+        user = request.user
+    if created:
+        CustomLogEntry.objects.add_something(user, instance)
+    else:
+        if update_fields:
+            update_fields = list(update_fields)
+        CustomLogEntry.objects.change_something(user, instance, update_fields)
+
+
+@receiver(post_delete)
+def log_delete(sender, instance, using, origin, **kwargs):
+    if sender is CustomLogEntry:
+        return
+    user = None
+    request = get_current_request()
+    if request:
+        user = request.user
+    CustomLogEntry.objects.delete_something(user, instance)