Some refactoring of the model manager methods

[pcdenotes.git] / notes / models.py

diff --git a/notes/models.py b/notes/models.py
index e4802217c3f4fb49853ad6aae494390eb04df19f..c38e3d50ae85d41986298f39ad5331c5744c09b7 100644 (file)
--- a/notes/models.py
+++ b/notes/models.py
@@ -1,12 +1,47 @@
 from django.db import models
+from django.db.models import Count
+from django.db.models.functions import ExtractYear, ExtractMonth
+from django.db.models.signals import pre_save
+
+from django.dispatch import receiver
 from django.contrib.auth.models import User
 from django.urls import reverse
 
+from datetime import datetime
+
 # Create your models here.
 
 NOTE_STATUS = ((0, "Draft"),
                (1, "Published"))            
 
+class NoteQuerySet(models.QuerySet):
+    pass
+
+class NoteManager(models.Manager):
+    def all_published(self):
+        return super().get_queryset().filter(status=1)
+
+    def all_with_unpublished(self):
+        return super().all()
+
+    def per_year(self, year):
+        return self.all_published().filter(created_at__year=year)
+
+    def per_month(self, year, month):
+        return self.per_year(year).filter(created_at__month=month)
+
+    def years(self):
+        return self.all_published().annotate(created_year=ExtractYear('created_at')).values_list('created_year', flat=True).distinct().order_by('created_year')
+
+    def years_with_total(self):
+        return self.all_published().annotate(created_year=ExtractYear('created_at')).values('created_year').annotate(total=Count('id')).order_by('created_year').values('created_year', 'total').distinct()
+
+    def months(self, year):
+        return self.per_year(year).annotate(created_month=ExtractMonth('created_at')).values_list('created_month', flat=True).distinct().order_by('created_month')
+
+    def months_with_total(self, year):
+        return self.per_year(year).annotate(created_month=ExtractMonth('created_at')).values('created_month').annotate(total=Count('id')).order_by('created_month').values('created_month', 'total').distinct()
+
 class Note(models.Model):
     title = models.CharField(max_length=250)
     slug = models.SlugField(max_length=250, unique=True)
@@ -16,6 +51,9 @@ class Note(models.Model):
     
     created_at = models.DateTimeField(auto_now_add=True)
     updated_at = models.DateTimeField(auto_now=True)
+    published_at = models.DateTimeField(null=True, editable=False)
+
+    objects = NoteManager()
 
     class Meta:
         ordering = ['-created_at']
@@ -25,5 +63,26 @@ class Note(models.Model):
 
     def get_absolute_url(self):
         return reverse("notes:note_detail", kwargs={"note_slug": self.slug})
-        #return "/notes/%s" % (self.slug)
 
+    def is_draft(self):
+        return self.status == 0
+
+    def is_published(self):
+        return self.status == 1
+
+    def publication_date(self):
+        if self.published_at is None:
+            return self.created_at
+        else:
+            return self.published_at
+
+@receiver(pre_save, sender=Note)
+def note_pre_save(sender, instance, **kwargs):
+    if instance.pk is None:
+        if instance.status == 1:
+            instance.published_at = datetime.now()
+    else:
+        old_instance = Note.objects.get(pk=instance.pk)
+        
+        if old_instance.status == 0 and instance.status == 1:
+            instance.published_at = datetime.now()
\ No newline at end of file