Added timezone field. Fix #127

mosquito_alert/geo/apps.py

@@ -1,6 +1,12 @@
 from django.apps import AppConfig
+from timezonefinder import TimezoneFinder
 
 
 class GeoConfig(AppConfig):
     default_auto_field = "django.db.models.BigAutoField"
     name = "mosquito_alert.geo"
+
+    def ready(self):
+        # Initialize the TimezoneFinder object and store it as a class attribute
+        # due to the first load is quite slow.
+        self.timezone_finder = TimezoneFinder()

mosquito_alert/geo/migrations/0003_location_timezone.py

@@ -0,0 +1,18 @@
+# Generated by Django 4.2.3 on 2023-11-30 17:10
+
+from django.db import migrations
+import timezone_field.fields
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("geo", "0002_alter_boundary_created_at_alter_boundary_updated_at_and_more"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="location",
+            name="timezone",
+            field=timezone_field.fields.TimeZoneField(blank=True, editable=False, null=True),
+        ),
+    ]

mosquito_alert/geo/models.py

@@ -13,6 +13,7 @@
     LifecycleModelMixin,
     hook,
 )
+from timezone_field import TimeZoneField
 from treebeard.mp_tree import MP_Node
 
 from mosquito_alert.utils.models import ParentManageableNodeMixin, TimeStampedModel
@@ -305,6 +306,7 @@ class LocationType(models.TextChoices):
 
     # Attributes - Mandatory
     point = models.PointField(geography=False)
+    timezone = TimeZoneField(null=True, blank=True, editable=False)
     location_type = models.CharField(max_length=3, choices=LocationType.choices, null=True, blank=True)
     # TODO: add positional_accuray (The uncertainty in meters around the latitude and longitude.)
 
@@ -313,12 +315,32 @@ class LocationType(models.TextChoices):
     objects = LocationManager()
 
     # Custom Properties
+    @property
+    def latitude(self):
+        return self.point.y
+
+    @property
+    def longitude(self):
+        return self.point.x
+
     # Methods
     @hook(AFTER_CREATE)
     @hook(AFTER_UPDATE, when="point", has_changed=True)
     def update_linked_boundaries(self):
         self.boundaries.set(Boundary.objects.reverse_geocoding(point=self.point).all())
 
+    @hook(BEFORE_CREATE)
+    @hook(BEFORE_UPDATE, when="point", has_changed=True)
+    def _update_timezone(self):
+        # Access the TimezoneFinder object from the AppConfig
+        timezone_finder = self._meta.app_config.timezone_finder
+
+        # Set the timezone using latitude and longitude
+        try:
+            self.timezone = timezone_finder.timezone_at(lat=self.latitude, lng=self.longitude)
+        except Exception:
+            pass
+
     # Meta and String
     class Meta:
         verbose_name = _("location")

mosquito_alert/geo/tests/test_models.py

@@ -385,12 +385,32 @@ def test_point_can_not_be_blank(self):
     def test_point_srid_is_4326(self):
         assert self.model._meta.get_field("point").srid == 4326
 
+    def test_timezone_can_be_null(self):
+        assert self.model._meta.get_field("timezone").null
+
+    def test_timezone_can_be_blank(self):
+        assert self.model._meta.get_field("timezone").blank
+
+    def test_timezone_is_not_editable(self):
+        assert not self.model._meta.get_field("timezone").editable
+
     def test_location_type_can_be_null(self):
         assert self.model._meta.get_field("location_type").null
 
     def test_location_type_can_be_blank(self):
         assert self.model._meta.get_field("location_type").blank
 
+    # properties
+    def test_latitude(self):
+        obj = self.factory_cls(point=Point(x=2.79, y=41.67, srid=4326))
+
+        obj.latitude == 41.67
+
+    def test_longitude(self):
+        obj = self.factory_cls(point=Point(x=2.79, y=41.67, srid=4326))
+
+        obj.latitude == 2.79
+
     # methods
     def test_update_boundaries_on_create(self, country_bl):
         bbox_poly_a = (0, 0, 10, 10)  # x0, y0, x1, y1
@@ -440,6 +460,30 @@ def test_update_boundaries_on_point_update(self, country_bl):
 
         assert list(location_in_a.boundaries.all()) == [boundary_b]
 
+    def test_timezone_is_auto_set_on_create(self):
+        # Blanes
+        obj = self.factory_cls(point=Point(x=2.70, y=41.61, srid=4326))
+        assert obj.timezone == "Europe/Madrid"
+
+    def test_timezone_is_updated_on_point_change(self):
+        # Blanes
+        obj = self.factory_cls(point=Point(x=2.70, y=41.61, srid=4326))
+        assert obj.timezone == "Europe/Madrid"
+
+        # Paris
+        obj.point = Point(x=2.37, y=49.03, srid=4326)
+        obj.save()
+        assert obj.timezone == "Europe/Paris"
+
+    def test_timezone_does_not_raise_on_ETC_timezones(self):
+        # Middle of the ocean
+        obj = self.factory_cls(point=Point(x=-36.38, y=41.50, srid=4326))
+        assert obj.timezone == "Etc/GMT+2"
+
+    def test_timezone_is_set_to_None_if_timezone_finder_raises(self):
+        obj = self.factory_cls(point=Point(x=80000, y=80000, srid=4326))
+        assert obj.timezone is None
+
     # meta
     def test__str__with_location_type(self):
         point = FuzzyPoint(srid=4326).fuzz()

requirements/base.txt

@@ -12,6 +12,7 @@ geopandas==0.12.2  # https://github.com/geopandas/geopandas
 tqdm==4.64.1
 geopy==2.3.0  # https://github.com/geopy/geopy
 anytree==2.8.0  # https://github.com/c0fec0de/anytree
+timezonefinder==6.2.0  # https://github.com/jannikmi/timezonefinder
 
 # Django
 # ------------------------------------------------------------------------------
@@ -37,6 +38,7 @@ django-notifications-hq==1.8.2  # https://github.com/django-notifications/django
 django-lb-health-check==1.0.1  # https://github.com/Hovercross/django-lb-health-check
 django-simple-history==3.3.0  # https://github.com/jazzband/django-simple-history
 django-jsonform==2.19.1  # https://github.com/bhch/django-jsonform
+django-timezone-field==6.1.0  # https://github.com/mfogel/django-timezone-field/
 # Django Admin
 django-admin-sortable2==2.1.8  # https://github.com/jrief/django-admin-sortable2
 django-nested-admin==4.0.2  # https://github.com/theatlantic/django-nested-admin