Django practice (9): Implements product Input Validation

Let's complete the task in the previous section:

1. Verify price> 0: It must be verified in form;
2. unique title verification: verification in model;
3. Verify the image_url Extension: Verify it in form, and change it to the urlfield type in model by the way.

The property cannot be empty in the previously generated scaffold:

However, the uniqueness of the URL format, the suffix of rul, and title is not verified. First, add the URL format and title uniqueness check in the model:

 

 
FromDjango. DBImportModelsClassProduct (models. Model): Title= Models. charfield (max_length = 100, unique =True) Description=Models. textfield () image_url= Models. urlfield (max_length = 200)) Price= Models. decimalfield (max_digits = 8, decimal_places = 2)
 

 

Add unique = true on the title and change the image_url type to urlfield:

 

The remaining image format suffix, price> 0 verification needs to be implemented in form:

Depot/depotapp/forms. py

 #  /Usr/bin/Python  #  Coding: utf8  From Django Import  Forms  From Models Import * Import  Itertools  Def Anytrue (predicate, sequence ):  Return True In  Itertools. IMAP (predicate, sequence)  Def Endswith (S ,* Endings ):  Return  Anytrue (S. endswith, endings)  Class  Productform (forms. modelform ):  Class  Meta: Model = Product  Def  _ Init __ (Self, * ARGs ,** Kwargs): Super (productform, self ).  _ Init __ (* ARGs ,** Kwargs)  Def  Clean_price (Self): Price = Self. cleaned_data [ '  Price  '  ]  If Price <= 0:  Raise Forms. validationerror ("  Price must be greater than zero  "  )  Return  Price  Def  Clean_image_url (Self): URL = Self. cleaned_data [ '  Image_url  '  ]  If   Not Endswith (URL, '  . Jpg ' , '  . PNG  ' , '  . Gif  '  ):  Raise Forms. validationerror ( '  The image format must be JPG, PNG, or GIF.  '  )  Return  URL 

Productform is inherited from modelform and can be automatically generated based on model attributes.

 

Added clean_price and clean_image_url verification on the generated productform. The result is as follows:

How are forms displayed? Take a look at the template:

Depot/depotapp/templates/depotapp/create_product.html

 

 {% Extends "base.html" % }{% block title %} create a product {% endblock % }{% block content %}  <  Table  >  <  Form  Action  = ""  Method  = "Post"  > {% Csrf_token %} {form }}  <  Tr  >      <  TD  Colspan  = "2"  Align  = "Right"  > <  Input  Type  = "Submit"  Value  = "CREATE"  /> </ TD  >    </  Tr  >  </  Form  >  </  Table  >  {% Endblock %} 

 

Directly output the form object ({fom} Will format the form into a form (table is used by default, or <p> or <li> can be specified through as_p and as_ul ), and contains the error message.

 

{% Csrf_token %} is used to add a token form item,Avoid repeated submissionPrevents cross-site forgery requests.