@cppgohan

with

Server-Sent Events

Flask?

Flask?MicroFramework again...

Flask?MicroFramework again...Written in Python

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=

Werkzeug

WSGI utility library

=

+Werkzeug

WSGI utility library

=

+Werkzeug

WSGI utility library

=

+Werkzeug

WSGI utility library

Jinja2

template engine

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Hello.py

Demo

Hello.py

Demo

Hello.py

Demo

index.html

Demo

index.html

Demo

result???

index.html

Demo

result???

• terminal run: python hello.py

• open http://localhost:5000

Server-Sent Event

server push的html5标准, 用法简易, 单次连接比polling高效些.

相比websocket的双向二进制数据, Server-Sent Event只是单向, HTTP协议. (但浏览器调试工具往往没法看到服务器发来的数据, X_X)

Server对Client的请求, 做stream方式的响应.

Server-Sent Event

Server-Sent Event

支持率不高, 暂时只能”玩”

要兼容处理

Demo

index.html

Demohello.py

Demoredis:

Demoredis:

demo:FILE_TEXT -- 每次python读出来的文本

demo:FILE_TEXT_SEQ -- 为文本版本号, 每次文本更新, 版本号+1

/sever_push响应 -- 当FILE_TEXT_SEQ增加时, 将最新的文本返回给浏览器

Demo

result???

Demo

result???

• terminal run: python hello.py

Demo

result???

• terminal run: python hello.py

• open http://localhost:5000

Demo

result???

• terminal run: python hello.py

• open http://localhost:5000

• block!!!

Demo

result???

• terminal run: python hello.py

• open http://localhost:5000

• block!!!

solution???

Demo

result???

• terminal run: python hello.py

• open http://localhost:5000

• block!!!

• async WSGI server! (eg. gunicorn + gevent, gevent)

solution???

Demo

result???

• terminal run: python hello.py

• open http://localhost:5000

• block!!!

• async WSGI server! (eg. gunicorn + gevent, gevent)

• terminal run: gunicorn -k gevent -b '0.0.0.0:5000' hello:app

solution???

Demo

result???

• terminal run: python hello.py

• open http://localhost:5000

• block!!!

• async WSGI server! (eg. gunicorn + gevent, gevent)

• terminal run: gunicorn -k gevent -b '0.0.0.0:5000' hello:app

• open http://localhost:5000

solution???

Demo

result???

• terminal run: python hello.py

• open http://localhost:5000

• block!!!

• async WSGI server! (eg. gunicorn + gevent, gevent)

• terminal run: gunicorn -k gevent -b '0.0.0.0:5000' hello:app

• open http://localhost:5000

• open http://localhost:5000 again!

solution???

More Demo

Server下发代码示例

More Demo

• start web server

• open http://localhost:5000

• server push js script...

• browser excute js script...

• ...

Server下发代码示例

More Usage

•网站动态更新

•区分客户端推送

•微博墙实现

•webgame服务器推送

•浏览器插件

Resources

• http://www.python.org/dev/peps/pep-0333/

• http://werkzeug.pocoo.org/

• http://jinja.pocoo.org/

• http://flask.pocoo.org/

• http://www.gevent.org/

• http://gunicorn.org/

• http://dev.w3.org/html5/eventsource/

• http://www.html5rocks.com/en/tutorials/eventsource/basics/

• http://www.w3schools.com/html/html5_serversentevents.asp

END; 2013, 分享不止!