Django Model creation Basics

Author:- Tushar Sonu Lambole

This post includes the basics of Model creation in Django

1. AutoIncrement and primary field
class ProjectMaster(models.Model):
    p_id = models.AutoField(primary_key=True)
   
2. Display text for model fields
class ProjectMaster(models.Model):
    p_name = models.CharField(verbose_name='Project Name', max_length=150)

3. Ordering the data in admin view 
class ProjectMaster(models.Model):
   class Meta:
        ordering = ('-p_date',)

4. Display model in admin site
class ProjectMasterAdmin(admin.ModelAdmin):
    list_display = ('p_id','p_name','p_description','p_date')

admin.site.register(ProjectMaster, ProjectMasterAdmin)

5. Foreign Key 
class ClientMaster(models.Model):
    c_id = models.AutoField(primary_key=True)
    p_fk = models.ForeignKey(ProjectMaster,verbose_name='Project')

6. ImageUploader with validation for ".png" extension and Dynamic ImagePath
class ClientMaster(models.Model):
   c_name = models.CharField(max_length=150,verbose_name='Name')

   def image_path(instance, filename):
        return os.path.join('ImagesFiles', str(instance.c_name), str(instance.c_name)+'.png')
 
   def validate_file_extension(value):
        if not value.name.endswith('.png'):
            raise ValidationError(u'Error: Only .Png files')

   c_logo = models.ImageField(upload_to=image_path, validators=[validate_file_extension],verbose_name='Logo Image')

7. View uploaded images 

A) in settings.py

MEDIA_ROOT = '/Users/tusharlambole/Documents/Development/Projects/DjangoProjects/PycharmProjects/TusharWebApp/'

MEDIA_URL = 'http://127.0.0.1:8000/'

B) in Url.py

urlpatterns = patterns('',
url(r'^(?P<path>.*)$', 'django.views.static.serve',
        {'document_root': settings.MEDIA_ROOT}),
)