[Fixed]-Django 2.7 Rest API Validation Request

Validation logic should be in forms.py file

for e.g.

def clean_columnname(self):
    columnname = self.cleaned_data['columnname']
    if len(columnname) < 1:
        raise ValidationError('Please add some content  ...')
    elif len(columnname) > 500000:
        raise ValidationError('Too many characters ...')
    return columnname