#
目录
[toc]
本章我们将介绍Django 管理工具及如何使用 Django 来创建项目，第一个项目我们以 HelloWorld 来命令项目。
I.Django管理工具
安装 Django 之后，您现在应该已经有了可用的管理工具 django-admin.py。我们可以使用 django-admin.py 来创建一个项目:
注意:这里第一眼看上去，还以为这里的django-admin.py是一个脚本，但事实上这里它是一个命令
我们可以来看下django-admin.py的命令介绍:
[root@master python_project]# ls
HelloWorld HeloWorld settings.py
可以看到当前目录下面并没有django-admin.py这个脚本，但是当你敲这个命令的时候是可以自动补齐的。
[root@master python_project]# django-admin.py
Type 'django-admin.py help <subcommand>' for help on a specific subcommand.
Available subcommands:
[django]
check
compilemessages
createcachetable
dbshell
diffsettings
dumpdata
flush
inspectdb
loaddata
makemessages
makemigrations
migrate
runserver
sendtestemail
shell
showmigrations
sqlflush
sqlmigrate
sqlsequencereset
squashmigrations
startapp
startproject
test
testserver
Note that only Django core commands are listed as settings are not properly configured (error: Requested setting INSTALLED_APPS, but settings are not configured. You must either define the environment variable DJANGO_SETTINGS_MODULE or call settings.configure() before accessing settings.).
这个命令并不是只有在这一个目录下才有，而是可以作为全局变量来调用。
i.使用which查看django-admin.py命令
[root@master python_project]# which django-admin.py
/usr/bin/django-admin.py
ii.查看django-admin.py
[root@master python_project]# cat /usr/bin/django-admin.py
#!/usr/bin/python
from django.core import management
if __name__ == "__main__":
management.execute_from_command_line()
II.创建第一个项目
i.创建项目
使用 django-admin.py 来创建 HelloWorld 项目：
django-admin.py startproject HelloWorld
1.创建HelloWorld 项目之前
[root@master python_project]# ls
settings.py
2.创建HelloWorld 项目
[root@master python_project]# django-admin.py startproject HelloWorld
3.创建HelloWorld 项目之后
[root@master python_project]# ls
HelloWorld settings.py
[root@master python_project]# tree HelloWorld/
HelloWorld/
├── HelloWorld
│ ├── __init__.py
│ ├── settings.py
│ ├── urls.py
│ └── wsgi.py
└── manage.py
1 directory, 5 files
注意：受过去影响，就是“所有代码都是自己写出来的"这种观念的影响。一开始还以为目录以及目录里面内容都需要自己来写。而操作之后发现，当你执行了
django-admin.py startproject HelloWorld这个命令之后，就会自动生成HelloWorld目录以及下面的内容。
ii.目录说明
HelloWorld: 项目的容器。manage.py: 一个实用的命令行工具，可让你以各种方式与该Django项目进行交互。HelloWorld/__init__.py: 一个空文件，告诉Python该目录是一个Python包。HelloWorld/settings.py: 该Django项目的设置/配置。HelloWorld/urls.py: 该Django项目的URL声明; 一份由Django驱动的网站"目录"。HelloWorld/wsgi.py: 一个WSGI兼容的Web服务器的入口，以便运行你的项目。
iii.查看目录中的代码具体内容
1.查看manage.py
[root@master HelloWorld]# cat manage.py
#!/usr/bin/env python
import os
import sys
if __name__ == "__main__":
os.environ.setdefault("DJANGO_SETTINGS_MODULE", "HelloWorld.settings")
try:
from django.core.management import execute_from_command_line
except ImportError:
# The above import may fail for some other reason. Ensure that the
# issue is really that Django is missing to avoid masking other
# exceptions on Python 2.
try:
import django
except ImportError:
raise ImportError(
"Couldn't import Django. Are you sure it's installed and "
"available on your PYTHONPATH environment variable? Did you "
"forget to activate a virtual environment?"
)
raise
execute_from_command_line(sys.argv)
[root@master HelloWorld]# cat __init__.py
[root@master HelloWorld]#
2.查看settings.py
[root@master HelloWorld]# cat settings.py
"""
Django settings for HelloWorld project.
Generated by 'django-admin startproject' using Django 1.10.3.
For more information on this file, see
https://docs.djangoproject.com/en/1.10/topics/settings/
For the full list of settings and their values, see
https://docs.djangoproject.com/en/1.10/ref/settings/
"""
import os
# Build paths inside the project like this: os.path.join(BASE_DIR, ...)
BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
# Quick-start development settings - unsuitable for production
# See https://docs.djangoproject.com/en/1.10/howto/deployment/checklist/
# SECURITY WARNING: keep the secret key used in production secret!
SECRET_KEY = 'f9onn^p_ngdj62*ja-yd7-wp7ec_q&w3&x00y-g@3qru034ocu'
# SECURITY WARNING: don't run with debug turned on in production!
DEBUG = True
ALLOWED_HOSTS = []
# Application definition
INSTALLED_APPS = [
'django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
]
MIDDLEWARE = [
'django.middleware.security.SecurityMiddleware',
'django.contrib.sessions.middleware.SessionMiddleware',
'django.middleware.common.CommonMiddleware',
'django.middleware.csrf.CsrfViewMiddleware',
'django.contrib.auth.middleware.AuthenticationMiddleware',
'django.contrib.messages.middleware.MessageMiddleware',
'django.middleware.clickjacking.XFrameOptionsMiddleware',
]
ROOT_URLCONF = 'HelloWorld.urls'
TEMPLATES = [
{
'BACKEND': 'django.template.backends.django.DjangoTemplates',
'DIRS': [],
'APP_DIRS': True,
'OPTIONS': {
'context_processors': [
'django.template.context_processors.debug',
'django.template.context_processors.request',
'django.contrib.auth.context_processors.auth',
'django.contrib.messages.context_processors.messages',
],
},
},
]
WSGI_APPLICATION = 'HelloWorld.wsgi.application'
# Database
# https://docs.djangoproject.com/en/1.10/ref/settings/#databases
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.sqlite3',
'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
}
}
# Password validation
# https://docs.djangoproject.com/en/1.10/ref/settings/#auth-password-validators
AUTH_PASSWORD_VALIDATORS = [
{
'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator',
},
{
'NAME': 'django.contrib.auth.password_validation.MinimumLengthValidator',
},
{
'NAME': 'django.contrib.auth.password_validation.CommonPasswordValidator',
},
{
'NAME': 'django.contrib.auth.password_validation.NumericPasswordValidator',
},
]
# Internationalization
# https://docs.djangoproject.com/en/1.10/topics/i18n/
LANGUAGE_CODE = 'en-us'
TIME_ZONE = 'UTC'
USE_I18N = True
USE_L10N = True
USE_TZ = True
# Static files (CSS, JavaScript, Images)
# https://docs.djangoproject.com/en/1.10/howto/static-files/
STATIC_URL = '/static/'
3.查看urls.py
[root@master HelloWorld]# cat urls.py
"""HelloWorld URL Configuration
The `urlpatterns` list routes URLs to views. For more information please see:
https://docs.djangoproject.com/en/1.10/topics/http/urls/
Examples:
Function views
1. Add an import: from my_app import views
2. Add a URL to urlpatterns: url(r'^$', views.home, name='home')
Class-based views
1. Add an import: from other_app.views import Home
2. Add a URL to urlpatterns: url(r'^$', Home.as_view(), name='home')
Including another URLconf
1. Import the include() function: from django.conf.urls import url, include
2. Add a URL to urlpatterns: url(r'^blog/', include('blog.urls'))
"""
from django.conf.urls import url
from django.contrib import admin
urlpatterns = [
url(r'^admin/', admin.site.urls),
]
4.查看wsgi.py
[root@master HelloWorld]# cat wsgi.py
"""
WSGI config for HelloWorld project.
It exposes the WSGI callable as a module-level variable named ``application``.
For more information on this file, see
https://docs.djangoproject.com/en/1.10/howto/deployment/wsgi/
"""
import os
from django.core.wsgi import get_wsgi_application
os.environ.setdefault("DJANGO_SETTINGS_MODULE", "HelloWorld.settings")
application = get_wsgi_application()
iv.启动服务器
接下来我们进入 HelloWorld 目录输入以下命令，启动服务器：
python manage.py runserver 0.0.0.0:8000
0.0.0.0让其它电脑可连接到开发服务器，8000为端口号。如果不说明，那么端口号默认为8000。
在浏览器输入你服务器的ip及端口号，如果正常启动，输出结果如下：
1.实际测试
[root@master HelloWorld]# ls
HelloWorld manage.py
[root@master HelloWorld]# python manage.py runserver 0.0.0.0:8000
Performing system checks...
System check identified no issues (0 silenced).
You have 13 unapplied migration(s). Your project may not work properly until you apply the migrations for app(s): admin, auth, contenttypes, sessions.
Run 'python manage.py migrate' to apply them.
November 25, 2016 - 08:33:27
Django version 1.10.3, using settings 'HelloWorld.settings'
Starting development server at http://0.0.0.0:8000/
Quit the server with CONTROL-C.
访问服务器报错提示
DisallowedHost at /
Invalid HTTP_HOST header: '192.168.142.32:8000'. You may need to add u'192.168.142.32' to ALLOWED_HOSTS.
Request Method: GET
Request URL: http://192.168.142.32:8000/
Django Version: 1.10.3
Exception Type: DisallowedHost
Exception Value:
Invalid HTTP_HOST header: '192.168.142.32:8000'. You may need to add u'192.168.142.32' to ALLOWED_HOSTS.
Exception Location: /usr/lib/python2.7/site-packages/django/http/request.py in get_host, line 113
Python Executable: /usr/bin/python
Python Version: 2.7.5
Python Path:
['/root/python_project/HelloWorld',
'/usr/lib64/python27.zip',
'/usr/lib64/python2.7',
'/usr/lib64/python2.7/plat-linux2',
'/usr/lib64/python2.7/lib-tk',
'/usr/lib64/python2.7/lib-old',
'/usr/lib64/python2.7/lib-dynload',
'/usr/lib64/python2.7/site-packages',
'/usr/lib64/python2.7/site-packages/gtk-2.0',
'/usr/lib/python2.7/site-packages']
Server time: Fri, 25 Nov 2016 08:34:42 +0000
访问了两次之后在CentOS7上面新增加的内容
Invalid HTTP_HOST header: '192.168.142.32:8000'. You may need to add u'192.168.142.32' to ALLOWED_HOSTS.
[25/Nov/2016 08:34:42] "GET / HTTP/1.1" 400 59517
Invalid HTTP_HOST header: '192.168.142.32:8000'. You may need to add u'192.168.142.32' to ALLOWED_HOSTS.
[25/Nov/2016 08:34:42] "GET /favicon.ico HTTP/1.1" 400 60254
2.解决问题
忽略了一个地方，就是启动之后
You have 13 unapplied migration(s). Your project may not work properly until you apply the migrations for app(s): admin, auth, contenttypes, sessions.
Run 'python manage.py migrate' to apply them.
2.1解决migrate问题
这里已经提示你了解决办法
python manage.py migrate
[root@master HelloWorld]# python manage.py migrate
Operations to perform:
Apply all migrations: admin, auth, contenttypes, sessions
Running migrations:
Applying contenttypes.0001_initial... OK
Applying auth.0001_initial... OK
Applying admin.0001_initial... OK
Applying admin.0002_logentry_remove_auto_add... OK
Applying contenttypes.0002_remove_content_type_name... OK
Applying auth.0002_alter_permission_name_max_length... OK
Applying auth.0003_alter_user_email_max_length... OK
Applying auth.0004_alter_user_username_opts... OK
Applying auth.0005_alter_user_last_login_null... OK
Applying auth.0006_require_contenttypes_0002... OK
Applying auth.0007_alter_validators_add_error_messages... OK
Applying auth.0008_alter_user_username_max_length... OK
Applying sessions.0001_initial... OK
再次启动
[root@master HelloWorld]# python manage.py runserver 0.0.0.0:8000
Performing system checks...
System check identified no issues (0 silenced).
November 25, 2016 - 08:51:20
Django version 1.10.3, using settings 'HelloWorld.settings'
Starting development server at http://0.0.0.0:8000/
Quit the server with CONTROL-C.
Invalid HTTP_HOST header: '192.168.142.32:8000'. You may need to add u'192.168.142.32' to ALLOWED_HOSTS.
[25/Nov/2016 08:51:28] "GET / HTTP/1.1" 400 60582
Invalid HTTP_HOST header: '192.168.142.32:8000'. You may need to add u'192.168.142.32' to ALLOWED_HOSTS.
[25/Nov/2016 08:51:28] "GET /favicon.ico HTTP/1.1" 400 60535
Invalid HTTP_HOST header: '192.168.142.32:8000'. You may need to add u'192.168.142.32' to ALLOWED_HOSTS.
[25/Nov/2016 08:52:17] "GET / HTTP/1.1" 400 60389
Invalid HTTP_HOST header: '192.168.142.32:8000'. You may need to add u'192.168.142.32' to ALLOWED_HOSTS.
[25/Nov/2016 08:52:18] "GET /favicon.ico HTTP/1.1" 400 60080
Invalid HTTP_HOST header: '192.168.142.32:8000'. You may need to add u'192.168.142.32' to ALLOWED_HOSTS.
[25/Nov/2016 08:52:18] "GET /favicon.ico HTTP/1.1" 400 60154
这个时候没有了上面的migrate提示，但是依旧是无法访问网页。
2.2解决ALLOWED_HOSTS
解决办法，搜素引擎帮助我找到了官网。
ALLOWED_HOSTS官网解释
然后从官网上看到 Changed in Django Development version: In older versions, ALLOWED_HOSTS wasn’t checked when running tests. In older versions, ALLOWED_HOSTS wasn’t checked if DEBUG=True. This was also changed in Django
1.10.3, 1.9.11, and 1.8.16 to prevent a DNS rebinding attack.
然后自己在报错的页面使用
Ctrl+F搜索ALLOWED_HOSTS
搜索结果图
中间改了一次但是自己没有在地址两边加''，即让它成为字符串，会报这个错误
[root@master HelloWorld]# python manage.py runserver 0.0.0.0:8000
Traceback (most recent call last):
File "manage.py", line 22, in <module>
execute_from_command_line(sys.argv)
File "/usr/lib/python2.7/site-packages/django/core/management/__init__.py", line 367, in execute_from_command_line
utility.execute()
File "/usr/lib/python2.7/site-packages/django/core/management/__init__.py", line 316, in execute
settings.INSTALLED_APPS
File "/usr/lib/python2.7/site-packages/django/conf/__init__.py", line 53, in __getattr__
self._setup(name)
File "/usr/lib/python2.7/site-packages/django/conf/__init__.py", line 41, in _setup
self._wrapped = Settings(settings_module)
File "/usr/lib/python2.7/site-packages/django/conf/__init__.py", line 97, in __init__
mod = importlib.import_module(self.SETTINGS_MODULE)
File "/usr/lib64/python2.7/importlib/__init__.py", line 37, in import_module
__import__(name)
File "/root/python_project/HelloWorld/HelloWorld/settings.py", line 28
ALLOWED_HOSTS = [192.168.142.32]
^
SyntaxError: invalid syntax
更改之后
[root@master HelloWorld]# grep ALLOWED_HOSTS settings.py
ALLOWED_HOSTS = ['192.168.142.32']
再次访问
查看服务
[root@master HelloWorld]# python manage.py runserver 0.0.0.0:8000
Performing system checks...
System check identified no issues (0 silenced).
November 25, 2016 - 09:01:21
Django version 1.10.3, using settings 'HelloWorld.settings'
Starting development server at http://0.0.0.0:8000/
Quit the server with CONTROL-C.
[25/Nov/2016 09:01:24] "GET / HTTP/1.1" 200 1767
Not Found: /favicon.ico
[25/Nov/2016 09:01:25] "GET /favicon.ico HTTP/1.1" 404 1945
[25/Nov/2016 09:13:53] "GET / HTTP/1.1" 200 1767
[25/Nov/2016 09:14:11] "GET / HTTP/1.1" 200 1767
[25/Nov/2016 09:14:27] "GET / HTTP/1.1" 200 1767
抓包
3.测试
DEBUG = False
[root@master HelloWorld]# grep DEBUG settings.py
DEBUG = False
[root@master HelloWorld]# python manage.py runserver 0.0.0.0:8000
CommandError: You must set settings.ALLOWED_HOSTS if DEBUG is False.
不开启DEBUG会提示需要设置settings.ALLOWED_HOSTS。
注释DEBUG
[root@master HelloWorld]# grep DEBUG settings.py
# DEBUG = True
[root@master HelloWorld]# python manage.py runserver 0.0.0.0:8000
CommandError: You must set settings.ALLOWED_HOSTS if DEBUG is False.
和上面的提示是一样的。
注释掉，但是写地址
# DEBUG = True
ALLOWED_HOSTS = ['192.168.142.32']
[root@master HelloWorld]# python manage.py runserver 0.0.0.0:8000
Performing system checks...
System check identified no issues (0 silenced).
November 25, 2016 - 09:22:50
Django version 1.10.3, using settings 'HelloWorld.settings'
Starting development server at http://0.0.0.0:8000/
Quit the server with CONTROL-C.
[25/Nov/2016 09:22:55] "GET / HTTP/1.1" 404 74
这个时候的报错是404
III.视图和URL 配置
i.原文档
在先前创建的 HelloWorld 目录下的 HelloWorld 目录新建一个 view.py 文件，并输入代码：
from django.http import HttpResponse
def hello(request):
return HttpResponse("Hello world ! ")
接着，绑定 URL 与视图函数。打开 urls.py 文件，删除原来代码，将以下代码复制粘贴到 urls.py 文件中：
from django.conf.urls import *
from HelloWorld.view import hello
urlpatterns = patterns("",
('^hello/$', hello),
)
整个目录结构如下：
[root@solar HelloWorld]# tree
.
|-- HelloWorld
| |-- __init__.py
| |-- __init__.pyc
| |-- settings.py
| |-- settings.pyc
| |-- urls.py # url 配置
| |-- urls.pyc
| |-- view.py # 添加的视图文件
| |-- view.pyc # 编译后的视图文件
| |-- wsgi.py
| `-- wsgi.pyc
`-- manage.py
完成后，启动 Django 开发服务器，并在浏览器访问打开浏览器并访问：
注意：项目中如果代码有改动，服务器会自动监测代码的改动并自动重新载入，所以如果你已经启动了服务器则不需手动重启。
ii.实际测试
实际按着这个测试是不成功的会提示：
[root@master HelloWorld]# python manage.py runserver 0.0.0.0:8000
Performing system checks...
Unhandled exception in thread started by <function wrapper at 0x1c45aa0>
Traceback (most recent call last):
File "/usr/lib/python2.7/site-packages/django/utils/autoreload.py", line 226, in wrapper
fn(*args, **kwargs)
File "/usr/lib/python2.7/site-packages/django/core/management/commands/runserver.py", line 121, in inner_run
self.check(display_num_errors=True)
File "/usr/lib/python2.7/site-packages/django/core/management/base.py", line 374, in check
include_deployment_checks=include_deployment_checks,
File "/usr/lib/python2.7/site-packages/django/core/management/base.py", line 361, in _run_checks
return checks.run_checks(**kwargs)
File "/usr/lib/python2.7/site-packages/django/core/checks/registry.py", line 81, in run_checks
new_errors = check(app_configs=app_configs)
File "/usr/lib/python2.7/site-packages/django/core/checks/urls.py", line 14, in check_url_config
return check_resolver(resolver)
File "/usr/lib/python2.7/site-packages/django/core/checks/urls.py", line 24, in check_resolver
for pattern in resolver.url_patterns:
File "/usr/lib/python2.7/site-packages/django/utils/functional.py", line 35, in __get__
res = instance.__dict__[self.name] = self.func(instance)
File "/usr/lib/python2.7/site-packages/django/urls/resolvers.py", line 313, in url_patterns
patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)
File "/usr/lib/python2.7/site-packages/django/utils/functional.py", line 35, in __get__
res = instance.__dict__[self.name] = self.func(instance)
File "/usr/lib/python2.7/site-packages/django/urls/resolvers.py", line 306, in urlconf_module
return import_module(self.urlconf_name)
File "/usr/lib64/python2.7/importlib/__init__.py", line 37, in import_module
__import__(name)
File "/root/python_project/HelloWorld/HelloWorld/urls.py", line 27, in <module>
urlpatterns = patterns("",
NameError: name 'patterns' is not defined
也是将NameError: name 'patterns' is not defined作为关键词作为检索
其实在上面的文档是要删除，而在具体的实践过程中是注释掉了。在出现问题的时候也是看了一下原来的代码。原来的代码中urlpatterns是列表，文档更改之后是元组。不是元组，应该是方法，按照文档中的建议，应该是*中包含了patterns方法。但是实际操作中发现这个是没有的。
1.最后实现的代码
view.py
[root@master HelloWorld]# cat view.py
from django.http import HttpResponse
def hello(request):
return HttpResponse("Hello world ! ")
urls.py
[root@master HelloWorld]# cat urls.py
"""HelloWorld URL Configuration
The `urlpatterns` list routes URLs to views. For more information please see:
https://docs.djangoproject.com/en/1.10/topics/http/urls/
Examples:
Function views
1. Add an import: from my_app import views
2. Add a URL to urlpatterns: url(r'^$', views.home, name='home')
Class-based views
1. Add an import: from other_app.views import Home
2. Add a URL to urlpatterns: url(r'^$', Home.as_view(), name='home')
Including another URLconf
1. Import the include() function: from django.conf.urls import url, include
2. Add a URL to urlpatterns: url(r'^blog/', include('blog.urls'))
"""
# Origin code
#from django.conf.urls import url
# from django.contrib import admin
# urlpatterns = [
# url(r'^admin/', admin.site.urls),
# ]
# from django.conf.urls import *
from HelloWorld.view import hello
from django.conf.urls import url
urlpatterns = [
url('^hello/$',hello),
]
访问结果
2.更改网页显示内容
[root@master HelloWorld]# cat view.py
from django.http import HttpResponse
def hello(request):
return HttpResponse("Complete the first project! That's Awesome! ")
