Initial

backend/app/fields.py

@@ -0,0 +1,29 @@
+from django import forms
+from django.core.validators import RegexValidator
+from django.db import models
+
+
+VALID_MONTH_ERR = 'Bitte gültiges Datum im Format YYYY oder YYYY-MM angeben.'
+MONTH_FORMAT = r'^(19|20)[0-9]{2}(-(0[1-9]|1[0-2]))?$'
+
+
+class MonthPicker(forms.widgets.Input):
+    input_type = 'text'
+
+    def get_context(self, name, value, attrs):
+        if attrs:
+            attrs.setdefault('placeholder', 'YYYY-MM')
+        context = super().get_context(name, value, attrs)
+        # context['widget']['type'] = 'month'
+        return context
+
+
+class MonthField(models.CharField):
+    def __init__(self, *args, **kwargs):
+        kwargs['max_length'] = 7
+        super().__init__(*args, **kwargs)
+        self.validators.append(RegexValidator(MONTH_FORMAT, VALID_MONTH_ERR))
+
+    def formfield(self, **kwargs):
+        kwargs['widget'] = MonthPicker
+        return super().formfield(**kwargs)