Initial commit from ZIP

evg-outbo-api/outbo/apps/core/fields.py

@@ -0,0 +1,122 @@
+from functools import partial
+
+from django import forms
+from django.db import models
+from django_extensions.db.fields import (
+    CreationDateTimeField as BaseCreationDateTimeField,
+    ModificationDateTimeField as BaseModificationDateTimeField,
+)
+from django_fsm import FSMFieldMixin
+
+from outbo.apps.core.forms import EnumChoiceField
+
+
+class CreationDateTimeField(BaseCreationDateTimeField):
+    """
+    CreationDateTimeField
+
+    By default, sets editable=False, blank=True, auto_now_add=True
+    """
+
+
+class ModificationDateTimeField(BaseModificationDateTimeField):
+    """
+    ModificationDateTimeField
+
+    By default, sets editable=False, blank=True, auto_now=True
+
+    Sets value to now every time the object is saved.
+    """
+
+
+class RemovalDateTimeField(models.DateTimeField):
+    """
+    RemovalDateTimeField
+
+    By default, sets editable=False, blank=True, null=True
+    """
+
+    def __init__(self, *args, **kwargs):
+        kwargs.setdefault("editable", False)
+        kwargs.setdefault("blank", True)
+        kwargs.setdefault("null", True)
+        models.DateTimeField.__init__(self, *args, **kwargs)
+
+    def get_internal_type(self):
+        return "DateTimeField"
+
+    def deconstruct(self):
+        name, path, args, kwargs = super().deconstruct()
+        if self.editable is not False:
+            kwargs["editable"] = True
+        if self.blank is not True:
+            kwargs["blank"] = False
+        if self.null is not True:
+            kwargs["null"] = False
+        return name, path, args, kwargs
+
+
+class FSMKeyField(FSMFieldMixin, models.ForeignKey):
+    def get_state(self, instance):
+        return instance.__dict__[self.attname]
+
+    def set_state(self, instance, state):
+        instance.__dict__[self.attname] = self.to_python(state)
+
+
+class EnumCharField(models.CharField):
+    def __init__(self, *args, **kwargs):
+        enum = kwargs.pop("enum", None)
+        if enum is not None:
+            if kwargs.get("choices", None) is not None:
+                raise ValueError("Cannot provide choices for EnumCharField")
+            kwargs["choices"] = [(item, item.value) for item in enum]
+        super().__init__(*args, **kwargs)
+        self.validators.pop()  # lengthvalidator not necessary on this one
+        self.enum = enum
+
+    def get_internal_type(self):
+        return "CharField"
+
+    def formfield(self, **kwargs):
+        enum_form_class = partial(EnumChoiceField, enum=self.enum)
+        defaults = {
+            "widget": forms.Select,
+            "form_class": enum_form_class,
+            "choices": [(str(item), item.value) for item in self.enum],
+        }
+        defaults.update(kwargs)
+        return super().formfield(**defaults)
+
+    def deconstruct(self):
+        name, path, args, kwargs = super().deconstruct()
+        kwargs["enum"] = self.enum
+        if "choices" in kwargs:
+            del kwargs["choices"]
+
+        return name, path, args, kwargs
+
+    def to_python(self, value):
+        value = super().to_python(value)
+        if value is not None:
+            if not isinstance(value, self.enum):
+                enum_name, enum_value = value.split(".", 1)
+                if enum_name == self.enum.__name__:
+                    return self.enum[enum_value]
+        return value
+
+    def get_prep_value(self, value):
+        value = super().get_prep_value(value)
+        if value is None:
+            return value
+
+        if isinstance(value, self.enum):
+            return str(value)
+        return value
+
+    def from_db_value(self, value, *args):
+        if value is not None:
+            enum_name, enum_value = value.split(".", 1)
+            if enum_name == self.enum.__name__:
+                return self.enum[enum_value]
+        return value