Sanic官翻-示例
示例
本文档的这一部分是示例代码的简单集合，可以帮助您快速开始应用程序开发。这些示例大多数都是经过分类的，并为您提供了Sanic存储库中的工作代码示例的链接。
基础示例
示例的这一部分是代码的集合，这些代码提供了sanic应用程序的简单用例示例。
简单Apps
一个简单的sanic应用程序，具有单个异步方法，具有文本和json类型响应。
# 文本响应
from sanic import Sanic
from sanic import response as res
app = Sanic(__name__)
@app.route("/")
async def test(req):
return res.text("I\'m a teapot", status=418)
if __name__ == '__main__':
app.run(host="0.0.0.0", port=8000)
# json响应
from sanic import Sanic
from sanic import response
app = Sanic(__name__)
@app.route("/")
async def test(request):
return response.json({"test": True})
if __name__ == '__main__':
app.run(host="0.0.0.0", port=8000)
视图组成的简单Apps
展示了使用sanic.viewes.HTTPMethodView的简单机制，以及将其扩展为为view提供自定义异步行为的方法。
from sanic import Sanic
from sanic.views import HTTPMethodView
from sanic.response import text
app = Sanic('some_name')
class SimpleView(HTTPMethodView):
def get(self, request):
return text('I am get method')
def post(self, request):
return text('I am post method')
def put(self, request):
return text('I am put method')
def patch(self, request):
return text('I am patch method')
def delete(self, request):
return text('I am delete method')
class SimpleAsyncView(HTTPMethodView):
async def get(self, request):
return text('I am async get method')
async def post(self, request):
return text('I am async post method')
async def put(self, request):
return text('I am async put method')
app.add_route(SimpleView.as_view(), '/')
app.add_route(SimpleAsyncView.as_view(), '/async')
if __name__ == '__main__':
app.run(host="0.0.0.0", port=8000, debug=True)
URL重定向
from sanic import Sanic
from sanic import response
app = Sanic(__name__)
@app.route('/')
def handle_request(request):
return response.redirect('/redirect')
@app.route('/redirect')
async def test(request):
return response.json({"Redirected": True})
if __name__ == '__main__':
app.run(host="0.0.0.0", port=8000)
命名URL重定向
Sanic提供了一种易于使用的方法，该方法通过名为url_for的帮助程序方法重定向请求，该方法以唯一的url名称作为参数，并为您返回为其分配的实际路由。这将有助于简化在应用程序的不同部分之间重定向用户所需的工作。
from sanic import Sanic
from sanic import response
app = Sanic(__name__)
@app.route('/')
async def index(request):
# generate a URL for the endpoint `post_handler`
url = app.url_for('post_handler', post_id=5)
# the URL is `/posts/5`, redirect to it
return response.redirect(url)
@app.route('/posts/<post_id>')
async def post_handler(request, post_id):
return response.text('Post - {}'.format(post_id))
if __name__ == '__main__':
app.run(host="0.0.0.0", port=8000, debug=True)
蓝图
Sanic提供了一项令人惊叹的功能，可以将您的API和路由归为一个逻辑集合，这些逻辑集合可以轻松导入并插入到您的任何sanic应用程序中，这称为蓝图
from sanic import Blueprint, Sanic
from sanic.response import file, json
app = Sanic(__name__)
blueprint = Blueprint('name', url_prefix='/my_blueprint')
blueprint2 = Blueprint('name2', url_prefix='/my_blueprint2')
blueprint3 = Blueprint('name3', url_prefix='/my_blueprint3')
@blueprint.route('/foo')
async def foo(request):
return json({'msg': 'hi from blueprint'})
@blueprint2.route('/foo')
async def foo2(request):
return json({'msg': 'hi from blueprint2'})
@blueprint3.route('/foo')
async def index(request):
return await file('websocket.html')
@app.websocket('/feed')
async def foo3(request, ws):
while True:
data = 'hello!'
print('Sending: ' + data)
await ws.send(data)
data = await ws.recv()
print('Received: ' + data)
app.blueprint(blueprint)
app.blueprint(blueprint2)
app.blueprint(blueprint3)
app.run(host="0.0.0.0", port=8000, debug=True)
日志记录增强
即使Sanic附带了一系列日志支持，它仍允许最终用户自定义应用程序运行时处理日志的方式。
from sanic import Sanic
from sanic import response
import logging
logging_format = "[%(asctime)s] %(process)d-%(levelname)s "
logging_format += "%(module)s::%(funcName)s():l%(lineno)d: "
logging_format += "%(message)s"
logging.basicConfig(
format=logging_format,
level=logging.DEBUG
)
log = logging.getLogger()
# Set logger to override default basicConfig
sanic = Sanic()
@sanic.route("/")
def test(request):
log.info("received request; responding with 'hey'")
return response.text("hey")
sanic.run(host="0.0.0.0", port=8000)
以下示例提供了一个示例代码，演示了sanic.app.Sanic.middleware()的用法，从而提供了一种机制，可为每个传入请求分配唯一的请求ID并通过aiotask-context记录它们。
'''
Based on example from https://github.com/Skyscanner/aiotask-context
and `examples/{override_logging,run_async}.py`.
Needs https://github.com/Skyscanner/aiotask-context/tree/52efbc21e2e1def2d52abb9a8e951f3ce5e6f690 or newer
$ pip install git+https://github.com/Skyscanner/aiotask-context.git
'''
import asyncio
import uuid
import logging
from signal import signal, SIGINT
from sanic import Sanic
from sanic import response
import uvloop
import aiotask_context as context
log = logging.getLogger(__name__)
class RequestIdFilter(logging.Filter):
def filter(self, record):
record.request_id = context.get('X-Request-ID')
return True
LOG_SETTINGS = {
'version': 1,
'disable_existing_loggers': False,
'handlers': {
'console': {
'class': 'logging.StreamHandler',
'level': 'DEBUG',
'formatter': 'default',
'filters': ['requestid'],
},
},
'filters': {
'requestid': {
'()': RequestIdFilter,
},
},
'formatters': {
'default': {
'format': '%(asctime)s %(levelname)s %(name)s:%(lineno)d %(request_id)s | %(message)s',
},
},
'loggers': {
'': {
'level': 'DEBUG',
'handlers': ['console'],
'propagate': True
},
}
}
app = Sanic(__name__, log_config=LOG_SETTINGS)
@app.middleware('request')
async def set_request_id(request):
request_id = request.headers.get('X-Request-ID') or str(uuid.uuid4())
context.set("X-Request-ID", request_id)
@app.route("/")
async def test(request):
log.debug('X-Request-ID: %s', context.get('X-Request-ID'))
log.info('Hello from test!')
return response.json({"test": True})
if __name__ == '__main__':
asyncio.set_event_loop(uvloop.new_event_loop())
server = app.create_server(host="0.0.0.0", port=8000, return_asyncio_server=True)
loop = asyncio.get_event_loop()
loop.set_task_factory(context.task_factory)
task = asyncio.ensure_future(server)
try:
loop.run_forever()
except:
loop.stop()
流支持
Sanic框架内置了对流式传输大文件的支持，以下代码说明了使用流式支持设置Sanic应用程序的过程。
from sanic import Sanic
from sanic.views import CompositionView
from sanic.views import HTTPMethodView
from sanic.views import stream as stream_decorator
from sanic.blueprints import Blueprint
from sanic.response import stream, text
bp = Blueprint('blueprint_request_stream')
app = Sanic('request_stream')
class SimpleView(HTTPMethodView):
@stream_decorator
async def post(self, request):
result = ''
while True:
body = await request.stream.get()
if body is None:
break
result += body.decode('utf-8')
return text(result)
@app.post('/stream', stream=True)
async def handler(request):
async def streaming(response):
while True:
body = await request.stream.get()
if body is None:
break
body = body.decode('utf-8').replace('1', 'A')
await response.write(body)
return stream(streaming)
@bp.put('/bp_stream', stream=True)
async def bp_handler(request):
result = ''
while True:
body = await request.stream.get()
if body is None:
break
result += body.decode('utf-8').replace('1', 'A')
return text(result)
async def post_handler(request):
result = ''
while True:
body = await request.stream.get()
if body is None:
break
result += body.decode('utf-8')
return text(result)
app.blueprint(bp)
app.add_route(SimpleView.as_view(), '/method_view')
view = CompositionView()
view.add(['POST'], post_handler, stream=True)
app.add_route(view, '/composition_view')
if __name__ == '__main__':
app.run(host='0.0.0.0', port=8000)
示例客户端应用程序，以通过客户端代码显示流式应用程序的用法。
import requests# Warning: This is a heavy process.data = ""for i in range(1, 250000): data += str(i)r = requests.post('http://0.0.0.0:8000/stream', data=data)print(r.text)
并发支持
Sanic支持在多个worker的支持下启动应用程序的功能。但是，必须限制每个进程/循环的并发性，以确保高效执行。代码的以下部分提供了一个简短的示例，说明如何借助asyncio.Semaphore限制并发性。
from sanic import Sanicfrom sanic.response import jsonimport asyncioimport aiohttpapp = Sanic(__name__)sem = None@app.listener('before_server_start')def init(sanic, loop): global sem concurrency_per_worker = 4 sem = asyncio.Semaphore(concurrency_per_worker, loop=loop)async def bounded_fetch(session, url): """ Use session object to perform 'get' request on url """ async with sem, session.get(url) as response: return await response.json()@app.route("/")async def test(request): """ Download and serve example JSON """ url = "https://api.github.com/repos/channelcat/sanic" async with aiohttp.ClientSession() as session: response = await bounded_fetch(session, url) return json(response)app.run(host="0.0.0.0", port=8000, workers=2)
通过Docker进行Sanic部署
通过docker和docker-compose部署sanic应用程序是一项容易完成的任务，以下示例提供了示例simple_server.py的部署
FROM python:3.5MAINTAINER Channel Cat <channelcat@gmail.com>ADD . /codeRUN pip3 install git+https://github.com/channelcat/sanicEXPOSE 8000WORKDIR /codeCMD ["python", "simple_server.py"]
version: '2'services: sanic: build: . ports: - "8000:8000"
监控和错误处理
Sanic通过sanic.handlers.ErrorHandler提供了全局异常处理程序的可扩展的最小实现。本示例说明如何扩展它以启用某些自定义行为。
"""Example intercepting uncaught exceptions using Sanic's error handler framework.This may be useful for developers wishing to use Sentry, Airbrake, etc.or a custom system to log and monitor unexpected errors in production.First we create our own class inheriting from Handler in sanic.exceptions,and pass in an instance of it when we create our Sanic instance. Inside thisclass' default handler, we can do anything including sending exceptions toan external service."""from sanic.handlers import ErrorHandlerfrom sanic.exceptions import SanicException"""Imports and code relevant for our CustomHandler class(Ordinarily this would be in a separate file)"""class CustomHandler(ErrorHandler): def default(self, request, exception): # Here, we have access to the exception object # and can do anything with it (log, send to external service, etc) # Some exceptions are trivial and built into Sanic (404s, etc) if not isinstance(exception, SanicException): print(exception) # Then, we must finish handling the exception by returning # our response to the client # For this we can just call the super class' default handler return super().default(request, exception)"""This is an ordinary Sanic server, with the exception that we set theserver's error_handler to an instance of our CustomHandler"""from sanic import Sanicapp = Sanic(__name__)handler = CustomHandler()app.error_handler = handler@app.route("/")async def test(request): # Here, something occurs which causes an unexpected exception # This exception will flow to our custom handler. raise SanicException('You Broke It!')if __name__ == '__main__': app.run(host="0.0.0.0", port=8000, debug=True)
使用外部服务提供商进行监视
import loggingimport socketfrom os import getenvfrom platform import nodefrom uuid import getnode as get_macfrom logdna import LogDNAHandlerfrom sanic import Sanicfrom sanic.response import jsonfrom sanic.request import Requestlog = logging.getLogger('logdna')log.setLevel(logging.INFO)def get_my_ip_address(remote_server="google.com"): with socket.socket(socket.AF_INET, socket.SOCK_DGRAM) as s: s.connect((remote_server, 80)) return s.getsockname()[0]def get_mac_address(): h = iter(hex(get_mac())[2:].zfill(12)) return ":".join(i + next(h) for i in h)logdna_options = { "app": __name__, "index_meta": True, "hostname": node(), "ip": get_my_ip_address(), "mac": get_mac_address()}logdna_handler = LogDNAHandler(getenv("LOGDNA_API_KEY"), options=logdna_options)logdna = logging.getLogger(__name__)logdna.setLevel(logging.INFO)logdna.addHandler(logdna_handler)app = Sanic(__name__)@app.middlewaredef log_request(request: Request): logdna.info("I was Here with a new Request to URL: {}".format(request.url))@app.route("/")def default(request): return json({ "response": "I was here" })if __name__ == "__main__": app.run( host="0.0.0.0", port=getenv("PORT", 8080) )
from os import getenvfrom raygun4py.raygunprovider import RaygunSenderfrom sanic import Sanicfrom sanic.exceptions import SanicExceptionfrom sanic.handlers import ErrorHandlerclass RaygunExceptionReporter(ErrorHandler): def __init__(self, raygun_api_key=None): super().__init__() if raygun_api_key is None: raygun_api_key = getenv("RAYGUN_API_KEY") self.sender = RaygunSender(raygun_api_key) def default(self, request, exception): self.sender.send_exception(exception=exception) return super().default(request, exception)raygun_error_reporter = RaygunExceptionReporter()app = Sanic(__name__, error_handler=raygun_error_reporter)@app.route("/raise")async def test(request): raise SanicException('You Broke It!')if __name__ == '__main__': app.run( host="0.0.0.0", port=getenv("PORT", 8080) )
import rollbarfrom sanic.handlers import ErrorHandlerfrom sanic import Sanicfrom sanic.exceptions import SanicExceptionfrom os import getenvrollbar.init(getenv("ROLLBAR_API_KEY"))class RollbarExceptionHandler(ErrorHandler): def default(self, request, exception): rollbar.report_message(str(exception)) return super().default(request, exception)app = Sanic(__name__, error_handler=RollbarExceptionHandler())@app.route("/raise")def create_error(request): raise SanicException("I was here and I don't like where I am")if __name__ == "__main__": app.run( host="0.0.0.0", port=getenv("PORT", 8080) )
from os import getenvfrom sentry_sdk import init as sentry_initfrom sentry_sdk.integrations.sanic import SanicIntegrationfrom sanic import Sanicfrom sanic.response import jsonsentry_init( dsn=getenv("SENTRY_DSN"), integrations=[SanicIntegration()],)app = Sanic(__name__)# noinspection PyUnusedLocal@app.route("/working")async def working_path(request): return json({ "response": "Working API Response" })# noinspection PyUnusedLocal@app.route("/raise-error")async def raise_error(request): raise Exception("Testing Sentry Integration")if __name__ == '__main__': app.run( host="0.0.0.0", port=getenv("PORT", 8080) )
安全
以下示例代码显示了一个基于装饰器的简单身份验证和授权机制，可以将其设置为保护sanic api端点。
# -*- coding: utf-8 -*-from sanic import Sanicfrom functools import wrapsfrom sanic.response import jsonapp = Sanic()def check_request_for_authorization_status(request): # Note: Define your check, for instance cookie, session. flag = True return flagdef authorized(f): @wraps(f) async def decorated_function(request, *args, **kwargs): # run some method that checks the request # for the client's authorization status is_authorized = check_request_for_authorization_status(request) if is_authorized: # the user is authorized. # run the handler method and return the response response = await f(request, *args, **kwargs) return response else: # the user is not authorized. return json({'status': 'not_authorized'}, 403) return decorated_function@app.route("/")@authorizedasync def test(request): return json({'status': 'authorized'})if __name__ == "__main__": app.run(host="0.0.0.0", port=8000)
Websocket
Sanic提供了轻松添加路由并将其映射到websocket处理程序的功能。
- 前端
<!DOCTYPE html><html> <head> <title>WebSocket demo</title> </head> <body> <script> var ws = new WebSocket('ws://' + document.domain + ':' + location.port + '/feed'), messages = document.createElement('ul'); ws.onmessage = function (event) { var messages = document.getElementsByTagName('ul')[0], message = document.createElement('li'), content = document.createTextNode('Received: ' + event.data); message.appendChild(content); messages.appendChild(message); }; document.body.appendChild(messages); window.setInterval(function() { data = 'bye!' ws.send(data); var messages = document.getElementsByTagName('ul')[0], message = document.createElement('li'), content = document.createTextNode('Sent: ' + data); message.appendChild(content); messages.appendChild(message); }, 1000); </script> </body></html>
- 后台
from sanic import Sanicfrom sanic.response import fileapp = Sanic(__name__)@app.route('/')async def index(request): return await file('websocket.html')@app.websocket('/feed')async def feed(request, ws): while True: data = 'hello!' print('Sending: ' + data) await ws.send(data) data = await ws.recv() print('Received: ' + data)if __name__ == '__main__': app.run(host="0.0.0.0", port=8000, debug=True)
vhost支持
from sanic import responsefrom sanic import Sanicfrom sanic.blueprints import Blueprint# Usage# curl -H "Host: example.com" localhost:8000# curl -H "Host: sub.example.com" localhost:8000# curl -H "Host: bp.example.com" localhost:8000/question# curl -H "Host: bp.example.com" localhost:8000/answerapp = Sanic()bp = Blueprint("bp", host="bp.example.com")@app.route('/', host=["example.com", "somethingelse.com", "therestofyourdomains.com"])async def hello(request): return response.text("Some defaults")@app.route('/', host="sub.example.com")async def hello(request): return response.text("42")@bp.route("/question")async def hello(request): return response.text("What is the meaning of life?")@bp.route("/answer")async def hello(request): return response.text("42")app.blueprint(bp)if __name__ == '__main__': app.run(host="0.0.0.0", port=8000)
具有并行测试运行支持的单元测试
以下示例显示了如何使用pytest-xdist插件提供的并行测试执行支持来启动并运行单元测试sanic应用程序。
"""pytest-xdist example for sanic serverInstall testing tools: $ pip install pytest pytest-xdistRun with xdist params: $ pytest examples/pytest_xdist.py -n 8 # 8 workers"""import refrom sanic import Sanicfrom sanic.response import textfrom sanic.testing import PORT as PORT_BASE, SanicTestClientimport pytest@pytest.fixture(scope="session")def test_port(worker_id): m = re.search(r'[0-9]+', worker_id) if m: num_id = m.group(0) else: num_id = 0 port = PORT_BASE + int(num_id) return port@pytest.fixture(scope="session")def app(): app = Sanic() @app.route('/') async def index(request): return text('OK') return app@pytest.fixture(scope="session")def client(app, test_port): return SanicTestClient(app, test_port)@pytest.mark.parametrize('run_id', range(100))def test_index(client, run_id): request, response = client._sanic_endpoint_test('get', '/') assert response.status == 200 assert response.text == 'OK'
修改请求对象
Sanic中的请求对象是一种dict对象，这意味着可以将请求对象作为常规dict对象进行操作。
from sanic import Sanicfrom sanic.response import textfrom random import randintapp = Sanic()@app.middleware('request')def append_request(request): # Add new key with random value request['num'] = randint(0, 100)@app.get('/pop')def pop_handler(request): # Pop key from request object num = request.pop('num') return text(num)@app.get('/key_exist')def key_exist_handler(request): # Check the key is exist or not if 'num' in request: return text('num exist in request') return text('num does not exist in reqeust')app.run(host="0.0.0.0", port=8000, debug=True)
有关更多示例和有用示例，请访问 Huge-Sanic’s GitHub Page
