django

Django FileField default file

最后都变了- 提交于 2021-02-16 05:00:10
问题 I have a model which contains FileField as below class Employer(models.Model): logo = models.FileField(storage=FileSystemStorage(location=settings.MEDIA_ROOT), upload_to='logos') The question is how can I add a default file like "{{ MEDIA_ROOT}}/logos/anonymous.jpg" to this filefield ? 回答1: You can specify the default file to use for that field as follows: class Employer(models.Model): logo = models.FileField(storage=FileSystemStorage(location=settings.MEDIA_ROOT), upload_to='logos', default=

Django入门到进阶-适合Python小白的系统课程

耗尽温柔 提交于 2021-02-15 23:16:41
download: Django入门到进阶-适合Python小白的系统课程 掌握Django的基础知识,学习Web的相关扩展知识,学会开发c/s服务与apiserver服务;学习多方面非Django内置模块的配置开发方法;学习真正生产环境的服务器最终部署方案;全面阐述Web开发的各个环节的知识点,让你在使用或不使用Django进行开发的情况下都可以顺利上手基于Python的Web服务,尽量涉及绝大部分Python Web开发的生态,并且做讲解知识浅中带细,易于理解,对初学者友好 适合人群 入门Python刚刚接触Web开发的同学 做Python运维的同学(基于Django开发相关Web业务) 做Python测试的同学 技术储备要求 掌握Python基础 了解前端基础 import random 2 if __name__ == " __main__ " : # 四位數字字母考證码的生成 3 checkcode= "" # 保管考證码的變量 4 for i in range(4 ): 5 index=random.randrange(0,4) # 生成一個0~3中的數 6 if index!=i and index +1 != i: 7 checkcode +=chr(random.randint(97,122)) # 生成a~z中的一個小寫字母 8 elif index +1==

Django 教程 --- Django 模型

时间秒杀一切 提交于 2021-02-15 16:59:35
一个 Django模块 是内置的功能,Django使用创建表,他们的田地,和各种约束。 简而言之,Django Models是与Django一起使用的SQL数据库。 SQL(结构化查询语言)很复杂,涉及许多不同的查询,用于创建,删除,更新或与数据库有关的任何其他内容。 Django模型简化了任务并将表组织到模型中。 通常,每个模型都映射到单个数据库表。 本文围绕如何使用Django模型方便地将数据存储在数据库中展开。 此外,我们可以使用Django的管理面板来创建,更新,删除或检索模型的字段以及各种类似的操作。 Django模型提供了简单性,一致性,版本控制和高级元数据处理。 模型的基础包括– 每个模型都是一个子类的Python类 django.db.models.Model 。 模型的每个属性代表一个数据库字段。 通过所有这些,Django为您提供了一个自动生成的数据库访问API。 请参阅进行 查询 。 from django.db import models # Create your models here. class GeeksModel (models.Model) : title = models.CharField(max_length = 200 ) description = models.TextField()

Django: Duplicated logic between properties and queryset annotations

只愿长相守 提交于 2021-02-15 14:56:25
问题 When I want to define my business logic, I'm struggling finding the right way to do this, because I often both need a property AND a custom queryset to get the same info. In the end, the logic is duplicated. Let me explain... First, after defining my class, I naturally start writing a simple property for data I need: class PickupTimeSlot(models.Model): @property def nb_bookings(self) -> int: """ How many times this time slot is booked? """ return self.order_set.validated().count() Then, I

Django组件——cookie与session

风格不统一 提交于 2021-02-15 12:14:01
一、会话跟踪技术 1、什么是会话跟踪技术   可以把会话理解为客户端与服务器之间的一次会晤,在一次会晤中可能会包含多次请求和响应。   在JavaWeb中,客户向某一服务器发出第一个请求开始,会话就开始了,直到客户关闭了浏览器会话结束。   在一个会话的多个请求中共享数据,这就是会话跟踪技术。例如在一个会话中的请求如下: 请求银行主页; 请求登录(请求参数是用户名和密码); 请求转账(请求参数与转账相关的数据); 请求信誉卡还款(请求参数与还款相关的数据)。   在这会话中 当前用户信息必须在这个会话中共享 的,因为登录的是张三,那么在转账和还款时一定是相对张三的转账和还款!这就说明我们必须在一个会话过程中有共享数据的能力。 2、会话路径技术使用Cookie或session完成    HTTP协议是无状态协议 ,也就是说每个请求都是独立的!无法记录前一次请求的状态。但HTTP协议中可以使用Cookie来完成会话跟踪!在Web开发中, 使用session来完成会话跟踪 , session底层依赖Cookie技术 。 二、Cookie 1、Cookie概述 (1)什么是Cookie?   Cookie翻译成中文是小甜点,小饼干的意思。在HTTP中它表示服务器送给客户端浏览器的小甜点。其实Cookie是key-value结构,类似于一个python中的字典。  

Django Channels VS Django 3.0 / 3.1?

▼魔方 西西 提交于 2021-02-15 11:47:13
问题 Can someone clarify the differences or complementarities between Django Channels Project and new Django native async support? From what I understood, Django-Channels is a project that have been started outside of Django, and then, started to be integrated in the core Django. But the current state of this work remains confusing to me. For example, today I'm using Django 2.2, and I'd like to add WebSocket support to my project. Should I: Upgrade to the latest Django version? Use Django Channels

Django Channels VS Django 3.0 / 3.1?

白昼怎懂夜的黑 提交于 2021-02-15 11:46:01
问题 Can someone clarify the differences or complementarities between Django Channels Project and new Django native async support? From what I understood, Django-Channels is a project that have been started outside of Django, and then, started to be integrated in the core Django. But the current state of this work remains confusing to me. For example, today I'm using Django 2.2, and I'd like to add WebSocket support to my project. Should I: Upgrade to the latest Django version? Use Django Channels

Django Channels VS Django 3.0 / 3.1?

隐身守侯 提交于 2021-02-15 11:45:35
问题 Can someone clarify the differences or complementarities between Django Channels Project and new Django native async support? From what I understood, Django-Channels is a project that have been started outside of Django, and then, started to be integrated in the core Django. But the current state of this work remains confusing to me. For example, today I'm using Django 2.2, and I'd like to add WebSocket support to my project. Should I: Upgrade to the latest Django version? Use Django Channels

Django 3.1 | Admin page appearance issue

♀尐吖头ヾ 提交于 2021-02-15 11:23:18
问题 Today I have updated Django to latest version 3.1. But for some reason when the logged in to admin page, all I cans see is a weird looking admin page. admin.py Can someone help me what went wrong or what are things I need to modify to get back to original admin page. Thanks in advance 回答1: In your projects' root urls.py file, simply add the below code to disable the new sidebar feature. from django.contrib import admin admin.autodiscover() admin.site.enable_nav_sidebar = False Reference:

Django 3.1 | Admin page appearance issue

匆匆过客 提交于 2021-02-15 11:23:10
问题 Today I have updated Django to latest version 3.1. But for some reason when the logged in to admin page, all I cans see is a weird looking admin page. admin.py Can someone help me what went wrong or what are things I need to modify to get back to original admin page. Thanks in advance 回答1: In your projects' root urls.py file, simply add the below code to disable the new sidebar feature. from django.contrib import admin admin.autodiscover() admin.site.enable_nav_sidebar = False Reference: