最快的 Python Web 框架入门

sanic是一款用 python3.5+ 写的 web framework，用法和 flask 类似，特点是非常快 。

Github 官网：https://github.com/channelcat/sanic

速度比较

安装

环境：python3.5+ 
python -m pip install sanic

Hello World

创建文件main.py，写入下面的内容

from sanic import Sanic
from sanic.response import json



    
app = Sanic(__name__)
@app.route("/")
async def test(request):
    return json({ "hello": "world" })
app.run(host="0.0.0.0", port=8000)

运行 python3 main.py 
sanic是不是看起来和flask一样

Request

属性 
request.files (dictionary of File objects) - 上传文件列表 
request.json (any) - json数据 
request.args (dict) - get数据 
request.form (dict) - post表单数据

例子

from sanic import Sanic
from sanic.response import json
@app.route("/json"


    
)
def post_json(request):
    return json({ "received": True, "message": request.json })
@app.route("/form")
def post_json(request):
    return json({ "received": True, "form_data": request.form, "test": request.form.get('test') })
@app.route("/files")
def post_json(request):
    test_file = request.files.get('test'


    
)
    file_parameters = {
        'body': test_file.body,
        'name': test_file.name,
        'type': test_file.type,
    }
    return json({ "received": True, "file_names": request.files.keys(), "test_file_parameters": file_parameters })
@app.route("/query_string")
def query_string(request):
    return json({ "parsed": True, "args":


    
 request.args, "url": request.url, "query_string": request.query_string })

路由

和flask差不多，一看就懂

from sanic import Sanic
from sanic.response import text
@app.route('/tag/')
async def person_handler(request, tag):
    return text('Tag - {}'.format(tag))
@app.route('/number/')
async def person_handler(request, integer_arg):
    return text('Integer - {}'.format


    
(integer_arg))
@app.route('/number/')
async def person_handler(request, number_arg):
    return text('Number - {}'.format(number))
@app.route('/person/')
async def person_handler(request, name):
    return text('Person - {}'.format(name))
@app.route('/folder/')
async def folder_handler(request, folder_id):
    return text('Folder - {}'.format(


    
folder_id))

注册中间件

app = Sanic(__name__)
@app.middleware
async def halt_request(request):
    print("I am a spy")
@app.middleware('request')
async def halt_request(request):
    return text('I halted the request')
@app.middleware('response')
async def halt_response(request, response):
    return text('I halted the response')



    
@app.route('/')
async def handler(request):
    return text('I would like to speak now please')
app.run(host="0.0.0.0", port=8000)

异常处理

抛出异常

from sanic import Sanic
from sanic.exceptions import ServerError
@app.route('/killme')
def i_am_ready_to_die(request):
    raise ServerError("Something bad happened")

处理异常

from sanic import


    
 Sanic
from sanic.response import text
from sanic.exceptions import NotFound
@app.exception(NotFound)
def ignore_404s(request, exception):
    return text("Yep, I totally found the page: {}".format(request.url))

蓝图

和flask中的蓝图一样，用于组织项目结构 
创建一个蓝图，相当于创建一个sanic app,上面的用法和上面相同，把app改成蓝图名称bp

from sanic.response import json
from sanic import Blueprint
bp = Blueprint('my_blueprint')
@bp.route('/')
async def


    
 bp_root():
    return json({'my': 'blueprint'})

蓝图注册到主app

from sanic import Sanic
from my_blueprint import bp
app = Sanic(__name__)
app.register_blueprint(bp)
app.run(host='0.0.0.0', port=8000, debug=True)

总结

sanic将是一个非常流行的框架．因为它基于python3.5+，使用了许多新的特性，这些特性让程序速度更快。

作者：Prasanta 

来源：https://segmentfault.com/a/1190000007193348

题图：pexels，CC0 授权。