Rails 和 Django 的深度技术对比

rails generate model Product name:string quantity_in_stock:integer

category:references

class Product < ActiveRecord::Base

end

create_table "products" , :force => true do |t|

t.string "name" ,

t.integer "quantity_in_stock" ,

t.integer "category_id" ,

t.datetime "created_at" , :null => false

t.datetime "updated_at" , :null => false

end

class Product(models.Model):

name = models.CharField()

quantity_in_stock = models.IntegerField()

category = models.ForeignKey( 'Category' )

created_at = models.DateTimeField(auto_now_add = True ) # set when it's created

updated_at = models.DateTimeField(auto_now = True ) # set every time it's updated

class Product(models.Model):

... # 旧字段

part_number = models.CharField()

class ProductsController < ApplicationController

# 自动渲染views/products/show.html.erb

def show

# params是包含请求变量的ruby hash

# 实例变量会自动被传递给视图

@product = Product.find(params[ :id ])

end

# 返回空的product，渲染views/products/new.html.erb

def new

@product = Product. new

end

# 接收用户提交的POST数据。多数来至于在'new'视图中表单

def create

@product = Product. new (params[ :product ])

if @product .save

redirect_to @product

else

# 重写渲染create.html.erb的默认行为

render "new"

end

end

end

# django通常称 'show' 方法为'detail'

# product_id 参数由route传递过来

def detail(request, product_id):

p = Product.objects.get(pk = product_id) # pk 表示主键

# 使用传递的第三个参数作为内容渲染detail.html

return render(request, 'products/detail.html' , { 'product' : p})

def create(request):

# 检查表单是否提交

if request.method = = 'POST' :

# 类似于RoR的 'create' 动作

form = ProductForm(request.POST) # 绑定于POST数据的表单

if form.is_valid(): # 所有的验证通过

new_product = form.save()

return HttpResponseRedirect(new_product.get_absolute_url())

else :

# 类似于RoR的 'new' 动作

form = ProductForm() # 空的表单

return render(request, 'products/create.html' , { 'form' : form })

# 假设route传递了名为 'pk' 的参数，包含对象的 id 并使用该id获得对象。

# 自动渲染视图 /products/product_detail.html

# 并将product作为上下文(context)变量传递给该视图

class ProductDetail(DetailView):

model = Product

# 为给定的模型生成表单。如果得到POST数据

# 自动验证表单并创建资源。

# 自动渲染视图 /products/product_create.html

# 并将表单作为上下文变量传递给视图

class ProductCreate(CreateView):

model = Product

class ProductDetail(DetailView):

model = Product

def get_object( self , queryset = None ):

return get_object_or_404(Product, key = self .kwargs.get( 'name' ))

def get_context_data( self , * * kwargs):

# 先调用基类函数获取上下文

context = super (ProductDetail, self ).get_context_data( * * kwargs)

# 在相关产品(product)中添加

context[ 'related_products' ] = self .get_object().related_products

return context

<%= form_tag("/contact", method: "post") do %>

<%= label_tag(:subject, "Subject:") %>

<%= text_field_tag(:subject) %>

<%= label_tag(:message, "Message:") %>

<%= text_field_tag(:message) %>

<%= label_tag(:subject, "Sender:") %>

<%= text_field_tag(:sender) %>

<%= label_tag(:subject, "CC myself:") %>

<%= check_box_tag(:sender) %>

<%= submit_tag("Search") %>

<% end %>

class ContactForm(forms.Form):

subject = forms.CharField(max_length = )

message = forms.CharField()

sender = forms.EmailField()

cc_myself = forms.BooleanField(required = False )

def contact(request):

if request.method = = 'POST' :

form = ContactForm(request.POST)

if form.is_valid():

return HttpResponseRedirect( '/thanks/' ) # POST之后重定向

else :

form = ContactForm() # An unbound form

return render(request, 'contact.html' , { 'form' : form })

< form action = "/contact/" method = "post" >

{{ form.as_p }} <!-- 生成类似于rails的表单 -->

< input type = "submit" value = "Submit" />

</ form >

# automatically maps GET /products/:id to products#show

# GET /products to products#index

# POST /products to products#create

# DELETE /products/:id to products#destroy

# etc.

resources :products

urlpatterns = patterns('',

# 在products控制器中匹配具体方法

url(r '^products/(?P\d+)/$' , products.views.DetailView.as_view(), name = 'detail' ),

# 匹配index方法就获得了主页

url(r '^products/$' , products.views.IndexView.as_view(), name = 'index' ),

url(r '^products/create/$' , products.views.CreateView.as_view(), name = 'create' ),

url(r '^products/(?P\d+)/delete/$' , products.views.DeleteView.as_view(), name = 'delete' ),

)

# users.yml (Rails当前知道我们在使用user的fixtures)

john:

name: John Smith

birthday: - -

profession: Blacksmith

bob:

name: Bob Costa

birthday: - -

profession: Surfer

[

{

"model" : "auth.user" ,

"fields" : {

"name" : "John Smith" ,

"birthday" : "1989-04-17" ,

"profession" : "Blacksmith" ,

}

},

{

"model" : "auth.user" ,

"fields" : {

"name" : "Bob Costa" ,

"birthday" : "1973-08-10" ,

"profession" : "Surfer" ,

}

}

]

class AnimalTest < ActiveSupport::TestCase

test "Animals that can speak are correctly identified" do

assert_equal animals( :lion ).speak(), 'The lion says "roar"'

assert_equal animals( :cat ).speak(), 'The cat says "meow"'

end

end

class AnimalTestCase(TestCase):

def test_animals_can_speak( self ):

"""Animals that can speak are correctly identified"""

# no way of directly accessing the fixtures, so we have to

# manually select the objects

lion = Animal.objects.get(name = "lion" )

cat = Animal.objects.get(name = "cat" )

self .assertEqual(lion.speak(), 'The lion says "roar"' )

self .assertEqual(cat.speak(), 'The cat says "meow"' )

class UsersControllerTest < ActionController::TestCase

test "should get index" do

get :index # 向index 动作发起GET请求

assert_response :success # 请求返回200

# assigns是包含所有实例变量的hash

assert_not_nil assigns( :users )

end

end

# assert_difference检查被测试的数字在开始和结束之间是否更改

assert_difference( 'Post.count' ) do

# 创建post

post :create , post: {title: 'Some title' }

end

class UsersTest(unittest.TestCase):

def setUp( self ):

self .client = Client()

def test_index( self ):

""" should get index """

response = self .client.get(reverse( 'users:index' ))

self .assertEqual(response.status_code, )

self .assertIsNotNone(response.context[ 'users' ])

gem 'nokogiri'

gem 'rails' , '3.0.0.beta3'

gem 'rack' , '>=1.0'

gem 'thin' , '~>1.1'

bundle install

desc "吃掉食物。在吃之前需要烹饪(Cooks)和设置表格(table)。"

task eat: [ :cook , :set_the_table ] do

# 在吃掉美味的食物之前, :cook和:set_the_table需要做完

# 吃的哪部分代码可以写在这里

end

rake eat

class Command(BaseCommand):

help = '吃掉食物'

def handle( self , * args, * * options):

call_command( 'cook' ) # 这里是如何在代码中调用管理命令

set_the_table() # 但子任务需要是常规的python函数

# 这里是吃的那些代码

# config/locales/en.yml

en: # the language identifier

greet_username: "Hello, %{user}!" # translation_key: "value"

# config/locales/pt.yml

pt:

greet_username: "Olá, %{user}!"

# locale/pt_BR/LC_MESSAGES/django.po

msgid "Hi, %(user)s." # key

msgstr "Olá, %(user)s" # 值 (翻译)