Django 1.10中文文档:第一个应用 part 1

已经同步到gitbook,想阅读的请转到gitbook: Django 1.10 中文文档

Let’s learn by example.


Throughout this tutorial, we’ll walk you through the creation of a basic poll application.


It’ll consist of two parts:

A public site that lets people view polls and vote in them.

An admin site that lets you add, change, and delete polls.




We’ll assume you have Django installed already. You can tell Django is installed and which version by running the following command:


python -m django --version

If Django is installed, you should see the version of your installation. If it isn’t, you’ll get an error telling “No module named django”.

如果已经安装Django,你将看到你安装的版本好。如果没有,将会报一个“No module named django”的错误

This tutorial is written for Django 1.10 and Python 3.4 or later. If the Django version doesn’t match, you can refer to the tutorial for your version of Django by using the version switcher at the bottom right corner of this page, or update Django to the newest version. If you are still using Python 2.7, you will need to adjust the code samples slightly, as described in comments.

本教程基于Django 1.10 以及 Python 3.4+版本编写。如果你的Django版本不符, 如果Django版本不符,可以通过当前页面右下角的版本转换器查看适用于你所使用的版本的Django教程,或者把Django升级到最新的版本。 如果你还在使用2.7版本的Python,你将需要按照注释中的内容稍微调整一下示例代码。

See How to install Django for advice on how to remove older versions of Django and install a newer one.

关于如何卸载旧版本并安装新版本的Django,请参考How to install Django

  • Where to get help:

If you’re having trouble going through this tutorial, please post a message to django-users or drop by #django on to chat with other Django users who might be able to help.

  • 如何获得帮助:

在本教程中,你有任何问题,都可以发消息给django 开发人员 或者访问 #django on irc.freenode.net网站,与其他Django开发者交流寻求帮助。

Creating a project


If this is your first time using Django, you’ll have to take care of some initial setup. Namely, you’ll need to auto-generate some code that establishes a Django project – a collection of settings for an instance of Django, including database configuration, Django-specific options and application-specific settings.

From the command line, cd

into a directory where you’d like to store your code, then run the following command:

如果这是你第一次使用Django,你需要注意一下初始化设置。换句话说,你需要使用命令行来自动创建一个Django项目 --一个Django框架开发的网站,包括数据库设置,针对Django的配置以及针对app应用的配置。


django-admin startproject mysite

This will create a mysite

directory in your current directory. If it didn’t work, see Problems running django-admin.

这将会在你的当前目录下创建一个mysite目录。如果没有,请查看Problems running django-admin.

  • NOTE

You’ll need to avoid naming projects after built-in Python or Django components. In particular, this means you should avoid using names like django (which will conflict with Django itself) or test (which conflicts with a built-in Python package).

  • 注意


  • Where should this code live?

If your background is in plain old PHP (with no use of modern frameworks), you’re probably used to putting code under the Web server’s document root (in a place such as /var/www). With Django, you don’t do that. It’s not a good idea to put any of this Python code within your Web server’s document root, because it risks the possibility that people may be able to view your code over the Web. That’s not good for security.

Put your code in some directory outside of the document root, such as /home/mycode.

  • 代码应该存在哪里



Let’s look at what startproject created:



These files are:

  • The outer mysite/ root directory is just a container for your project. Its name doesn’t matter to Django; you can rename it to anything you like.

  • A command-line utility that lets you interact with this Django project in various ways. You can read all the details about in django-admin and

  • The inner mysite/ directory is the actual Python package for your project. Its name is the Python package name you’ll need to use to import anything inside it (e.g. mysite.urls).

  • mysite/ An empty file that tells Python that this directory should be considered a Python package. If you’re a Python beginner, read more about packages in the official Python docs.

  • mysite/ Settings/configuration for this Django project. Django settings will tell you all about how settings work.

  • mysite/ The URL declarations for this Django project; a “table of contents” of your Django-powered site. You can read more about URLs in URL dispatcher.

  • mysite/ An entry-point for WSGI-compatible web servers to serve your project. See How to deploy with WSGIfor more details.


  • 外层的mysite/根目录仅仅是一个项目容器。它的命名对Django无关,你可以把它重命名为任何你喜欢的名字。


  • 内层的mysite/目录是你的项目的真正的Python包。它是你导入任何东西时将需要使用的Python包的名字(例如 mysite.urls。

  • mysite/一个空文件,它告诉Python这个目录应该被看做一个Python包。如果你是一个Python初学者,关于包的更多内容请阅读Python的官方文档)。

  • mysite/该Django 项目的设置/配置。Django 设置 将告诉你这些设置如何工作。

  • mysite/该Django项目的URL声明;你的Django站点的“目录”。

你可以在URL 转发器 中阅读到关于URL的更多内容。

  • mysite/用于你的项目的与WSGI兼容的Web服务器入口。


The development server**
Let’s verify your Django project works. Change into the outer mysite directory, if you haven’t already, and run the following commands:

python runserver

You’ll see the following output on the command line:


Performing system checks...
System check identified no issues (0 silenced).
You have unapplied migrations; your app may not work properly until they are applied.Run 'python migrate' to apply them.
March 01, 2017 - 15:50:53
Django version 1.10, using settings 'mysite.settings'Starting development server at [](
Quit the server with CONTROL-C.
  • Note

Ignore the warning about unapplied database migrations for now; we’ll deal with the database shortly.

  • 注意


You’ve started the Django development server, a lightweight Web server written purely in Python. We’ve included this with Django so you can develop things rapidly, without having to deal with configuring a production server – such as Apache – until you’re ready for production.


Now’s a good time to note: don’t use this server in anything resembling a production environment. It’s intended only for use while developing. (We’re in the business of making Web frameworks, not Web servers.)

Now that the server’s running, visit with your Web browser. You’ll see a “Welcome to Django” page, in pleasant, light-blue pastel. It worked!


服务器运行后,浏览器访问http:// ,你可以看到令人赏星悦目的淡蓝色的Django欢迎页面,它工作了。

  • Changing the port

By default, the runserver command starts the development server on the internal IP at port 8000.

If you want to change the server’s port, pass it as a command-line argument. For instance, this command starts the server on port 8080:

  • 更改端口

默认默认情况下,runserver 命令启动的开发服务器运行在内部IP的8000端口。如果你想更改端口,需要加个参数,比如说,下面这个命令开启了8080端口

python runserver 8080

If you want to change the server’s IP, pass it along with the port. So to listen on all public IPs (useful if you want to show off your work on other computers on your network), use:


python runserver

Full docs for the development server can be found in the runserver reference.


The development server automatically reloads Python code for each request as needed. You don’t need to restart the server for code changes to take effect. However, some actions like adding files don’t trigger a restart, so you’ll have to restart the server in these cases.

开发服务器会根据需要自动重新载入Python代码。 你不必为了使更改的代码生效而重启服务器。 然而,一些行为比如添加文件,不会触发服务器的重启,所以在这种情况下你需要手动重启服务器。


Now that your environment – a “project” – is set up, you’re set to start doing work.


Each application you write in Django consists of a Python package that follows a certain convention. Django comes with a utility that automatically generates the basic directory structure of an app, so you can focus on writing code rather than creating directories.


  • Projects vs. apps

What’s the difference between a project and an app? An app is a Web application that does something – e.g., a Weblog system, a database of public records or a simple poll app. A project is a collection of configuration and apps for a particular website. A project can contain multiple apps. An app can be in multiple projects.


Your apps can live anywhere on your Python path. In this tutorial, we’ll create our poll app right next to your file so that it can be imported as its own top-level module, rather than a submodule of mysite.
To create your app, make sure you’re in the same directory as and type this command:

你的应用可以放在Python path的任何位置。在本教程,我们将投票应用放在manage.py文件同级目录下,这样就可以作为顶层模块导入,而不是mysite的子模块。进入到manage.py的同级目录下,输入一下命令:

python startapp polls

That’ll create a directory polls, which is laid out like this:



This directory structure will house the poll application.


Write your first view

Let’s write the first view. Open the file polls/ and put the following Python code in it:


from django.http import HttpResponse

def index(request):
return HttpResponse("Hello, world. You're at the polls index.")

This is the simplest view possible in Django. To call the view, we need to map it to a URL - and for this we need a URLconf.

To create a URLconf in the polls directory, create a file called Your app directory should now look like:



In the polls/ file include the following code:

from django.conf.urls import url

from . import views

urlpatterns = [
url(r'^$', views.index, name='index'),

The next step is to point the root URLconf at the polls.urls module. In mysite/, add an import for django.conf.urls.include and insert an include() in the urlpatterns list, so you have:


# mysite/
from django.conf.urls import include, url
from django.contrib import admin

urlpatterns = [
url(r'^polls/', include('polls.urls')),

The include() function allows referencing other URLconfs. Note that the regular expressions for the include() function doesn’t have a $ (end-of-string match character) but rather a trailing slash. Whenever Django encounters include(), it chops off whatever part of the URL matched up to that point and sends the remaining string to the included URLconf for further processing.


The idea behind include() is to make it easy to plug-and-play URLs. Since polls are in their own URLconf (polls/, they can be placed under “/polls/”, or under “/fun_polls/”, or under “/content/polls/”, or any other path root, and the app will still work.

include()的设计思想是方便即插即用。由于polls在它自己的URLconf(polls/,你可以用“/polls/”, “/fun_polls/”, “/content/polls/”或者其他任意主目录随意替换,它仍可以正常工作。

When to use include()

You should always use include() when you include other URL is the only exception to this.


Doesn’t match what you see?

If you’re seeing include( instead of just, you’re probably using a version of Django that doesn’t match this tutorial version. You’ll want to either switch to the older tutorial or the newer Django version.


You have now wired an index view into the URLconf. Lets verify it’s working, run the following command:


python runserver

Go to http://localhost:8000/polls/ in your browser, and you should see the text “Hello, world. You’re at the polls index.”, which you defined in the index

The url() function is passed four arguments, two required: regex and view, and two optional: kwargs, and name. At this point, it’s worth reviewing what these arguments are for.

在你的浏览器访问http://localhost:8000/polls/,你将看到“Hello, world. You’re at the polls index.”,这就是我们刚刚在index view函数定义的。


url() argument: regex**

The term “regex” is a commonly used short form meaning “regular expression”, which is a syntax for matching patterns in strings, or in this case, url patterns. Django starts at the first regular expression and makes its way down the list, comparing the requested URL against each regular expression until it finds one that matches.

“正则”是正则表达式的通用缩写,它是一种匹配字符串或url地址的语法。在这里就是指url patterns。Django拿着用户请求的url地址,在urls.py文件中对urlpatterns列表中的每一项条目从头开始进行逐一对比,直到匹配为止。

Note that these regular expressions do not search GET and POST parameters, or the domain name. For example, in a request to, the URLconf will look for myapp/. In a request to, the URLconf will also look for myapp/.

需要注意的是,regex不会去匹配GET或POST参数或域名,例如对于, regex只尝试匹配myapp/。对于, regex也只尝试匹配myapp/。

If you need help with regular expressions, see Wikipedia’s entry and the documentation of the re module. Also, the O’Reilly book “Mastering Regular Expressions” by Jeffrey Friedl is fantastic. In practice, however, you don’t need to be an expert on regular expressions, as you really only need to know how to capture simple patterns. In fact, complex regexes can have poor lookup performance, so you probably shouldn’t rely on the full power of regexes.

如果你想深入研究正则表达式,可以参考Wikipedia’s entry 以及 re 模块的文档,由作者Jeffrey Friedl出版的O’Reilly “Mastering Regular Expressions”书籍也非常不错。但是实践中,你不需要多高深的正则表达式知识,因为你只需要知道如何匹配简单的规则。事实上,复杂的正则表达式查询性能会比较差,所以尽可能不用正则的复杂功能

Finally, a performance note: these regular expressions are compiled the first time the URLconf module is loaded. They’re super fast (as long as the lookups aren’t too complex as noted above).


url() argument: view

When Django finds a regular expression match, Django calls the specified view function, with an HttpRequest object as the first argument and any “captured” values from the regular expression as other arguments. If the regex uses simple captures, values are passed as positional arguments; if it uses named captures, values are passed as keyword arguments. We’ll give an example of this in a bit.


url() argument: kwargs

Arbitrary keyword arguments can be passed in a dictionary to the target view. We aren’t going to use this feature of Django in the tutorial.


url() argument: name

Naming your URL lets you refer to it unambiguously from elsewhere in Django, especially from within templates. This powerful feature allows you to make global changes to the URL patterns of your project while only touching a single file.
When you’re comfortable with the basic request and response flow, read part 2 of this tutorialto start working with the database.

对你的URL进行命名,可以让你能够在Django的任意处,尤其是模板内显式地引用它。这个强大的功能,仅仅通过创建一个文件就可以让你在项目里任意修改URL patterns这个全局变量的值。如果你已经掌握了基本的request和response的过程,那就阅读教程第二部分 数据库开始学习数据库相关