Django实战（4）：scaffold生成物分析

在上一节用一个插件生成了类似rails的scaffold，其实无非就是URLconf+MTV。让我们看看具体都生成了哪些东西。
首先是“入口”的定义即URLconf，打开urls.py:

from django.conf.urls.defaults import patterns, include, url
from depot.views import hello

urlpatterns = patterns('',
     url(r'^hello/ hello),
)
urlpatterns += patterns ('',
 (r'^depotapp/', include('depotapp.urls')),
)

上面的代码中增加的配置行表示：以depotapp开头的url由depotapp/urls.py文件进行处理。

django的url配置中，除了（正则表达式，view函数）的方式外，还支持（正则表达式，include文件）的方式。通常把app自身相关的url写到自己的url配置文件中，然后在project中引用。

接下来看一下生成的depotapp/urls.py的内容：

from django.conf.urls.defaults import *
from models import *
from views import *

urlpatterns = patterns('',
    (r'product/create/$', create_product),
    (r'product/list/$', list_product ),
    (r'product/edit/(?P[^/]+)/$', edit_product),
    (r'product/view/(?P[^/]+)/$', view_product),
)

将CRU（没有D)的URL映射到了视图。而视图在depotapp/views.py中定义：

from django import forms
from django.template import RequestContext
from django.http import HttpResponse, HttpResponseRedirect
from django.template.loader import get_template
from django.core.paginator import Paginator
from django.core.urlresolvers import reverse

# app specific files

from models import *
from forms import *

def create_product(request):
    form = ProductForm(request.POST or None)
    if form.is_valid():
        form.save()
        form = ProductForm()

    t = get_template('depotapp/create_product.html')
    c = RequestContext(request,locals())
    return HttpResponse(t.render(c))

def list_product(request):

    list_items = Product.objects.all()
    paginator = Paginator(list_items ,)

    try:
        page = int(request.GET.get('page', ''))
    except ValueError:
        page = 

    try:
        list_items = paginator.page(page)
    except :
        list_items = paginator.page(paginator.num_pages)

    t = get_template('depotapp/list_product.html')
    c = RequestContext(request,locals())
    return HttpResponse(t.render(c))

def view_product(request, id):
    product_instance = Product.objects.get(id = id)

    t=get_template('depotapp/view_product.html')
    c=RequestContext(request,locals())
    return HttpResponse(t.render(c))

def edit_product(request, id):

    product_instance = Product.objects.get(id=id)

    form = ProductForm(request.POST or None, instance = product_instance)

    if form.is_valid():
        form.save()

    t=get_template('depotapp/edit_product.html')
    c=RequestContext(request,locals())
    return HttpResponse(t.render(c))

视图中的相关内容比较多，主要的是模板，其次还有模型类、Paginator分页器、Form表单等等。

基本涵盖了典型的web应用交互的内容。