内容原子官方文档：
Tornado基础
模板和UI
模板可以使用多种模板语言，通过 RequestHandler.render整合到系统中，简单渲染字符串通过RequestHandler.write
配置模板
默认会在py文件相同目录查找模板，在其他位置可以使用template_path Application setting 或者覆盖 RequestHandler.get_template_path 。如果不是文件系统的位置，可以通过 tornado.template.BaseLoader子类并传入一个template_loader 实例。 模板缓存默认开启，如果想关闭可以设置compiled_template_cache=False 或者debug=True 。
模板语法
<html>
<head>
<title>{{ title }}</title>
</head>
<body>
<ul>
{% for item in items %}
<li>{{ escape(item) }}</li>
{% end %}
</ul>
</body>
</html>调用
class MainHandler(tornado.web.RequestHandler):
def get(self):
items = ["Item 1", "Item 2", "Item 3"]
self.render("template.html", title="My title", items=items)表达式： 支持RequestHandler.render and render_string，需要用于RequestHandler内，如果使用tornado.template，有部分无法支持。
escape: alias for tornado.escape.xhtml_escape
xhtml_escape: alias for tornado.escape.xhtml_escape
url_escape: alias for tornado.escape.url_escape
json_encode: alias for tornado.escape.json_encode
squeeze: alias for tornado.escape.squeeze
linkify: alias for tornado.escape.linkify
datetime: the Python datetime module
handler: the current RequestHandler object
request: alias for handler.request
current_user: alias for handler.current_user
locale: alias for handler.locale
_: alias for handler.locale.translate
static_url: alias for handler.static_url
xsrf_form_html: alias for handler.xsrf_form_html
reverse_url: alias for Application.reverse_url
All entries from the ui_methods and ui_modules Application settings
Any keyword arguments passed to render or render_string
界面模块
界面模块是一种可重用组件，例如博客的主页面和内容页都使用显示一条博客功能。
定义Entry模块，文件名uimodules.py
class Entry(tornado.web.UIModule): def render(self, entry, show_comments=False): return self.render_string( "module-entry.html", entry=entry, show_comments=show_comments
主程序中设置使用ui_modules。
from . import uimodulesclass HomeHandler(tornado.web.RequestHandler):
def get(self):
entries = self.db.query("SELECT * FROM entries ORDER BY date DESC")
self.render("home.html", entries=entries)class EntryHandler(tornado.web.RequestHandler):
def get(self, entry_id):
entry = self.db.get("SELECT * FROM entries WHERE id = %s", entry_id)
if not entry: raise tornado.web.HTTPError(404)
self.render("entry.html", entry=entry)settings = {
"ui_modules": uimodules,}application = tornado.web.Application([
(r"/", HomeHandler),
(r"/entry/([0-9]+)", EntryHandler),], **settings)模板的首页面中调用Entry 模块
{% for entry in entries %}
{% module Entry(entry) %}
{% end %}模板的内容页调用Entry 模块
{% module Entry(entry, show_comments=True) %}模型定义可以使用embedded_css,embedded_javascript, javascript_files, or css_files 方法:
class Entry(tornado.web.UIModule):
def embedded_css(self):
return ".entry { margin-bottom: 1em; }"
def render(self, entry, show_comments=False):
return self.render_string(
"module-entry.html", show_comments=show_comments)或者直接定义在模板中
{{ set_resources(embedded_css=".entry { margin-bottom: 1em; }") }}
<!-- more template html... -->调用带有嵌入内容的模板
{% module Template("module-entry.html", show_comments=True) %}授权和安全
配置加密cookie
application = tornado.web.Application([ (r"/", MainHandler), ], cookie_secret="__TODO:_GENERATE_YOUR_OWN_RANDOM_VALUE_HERE__")
可以使用 set_secure_cookie and get_secure_cookie方法使用加密cookie。
class MainHandler(tornado.web.RequestHandler):
def get(self):
if not self.get_secure_cookie("mycookie"):
self.set_secure_cookie("mycookie", "myvalue")
self.write("Your cookie was not set yet!")
else:
self.write("Your cookie was set!")
用户授权
当前已授权的用户会保持在请求处理器的self.current_user中，并且在模板变量current_user中。
下面是使用加密cookie保存数据方式的用户登录授权实例：
class BaseHandler(tornado.web.RequestHandler):
def get_current_user(self):
return self.get_secure_cookie("user")class MainHandler(BaseHandler):
def get(self):
if not self.current_user:
self.redirect("/login")
return
name = tornado.escape.xhtml_escape(self.current_user)
self.write("Hello, " + name)class LoginHandler(BaseHandler):
def get(self):
self.write('<html><body><form action="/login" method="post">'
'Name: <input type="text" name="name">'
'<input type="submit" value="Sign in">'
'</form></body></html>')
def post(self):
self.set_secure_cookie("user", self.get_argument("name"))
self.redirect("/")application = tornado.web.Application([
(r"/", MainHandler),
(r"/login", LoginHandler),], cookie_secret="__TODO:_GENERATE_YOUR_OWN_RANDOM_VALUE_HERE__")可以通过 tornado.web.authenticated装饰器使用授权状态。
class MainHandler(BaseHandler):
@tornado.web.authenticated
def get(self):
name = tornado.escape.xhtml_escape(self.current_user)
self.write("Hello, " + name)settings = {
"cookie_secret": "__TODO:_GENERATE_YOUR_OWN_RANDOM_VALUE_HERE__",
"login_url": "/login",}application = tornado.web.Application([
(r"/", MainHandler),
(r"/login", LoginHandler),], **settings)XSRF
启用XSRF
settings = {
"cookie_secret": "__TODO:_GENERATE_YOUR_OWN_RANDOM_VALUE_HERE__",
"login_url": "/login",
"xsrf_cookies": True,}application = tornado.web.Application([
(r"/", MainHandler),
(r"/login", LoginHandler),], **settings)使用XSRF在普通表单
<form action="/new_message" method="post">
{% module xsrf_form_html() %}
<input type="text" name="message"/>
<input type="submit" value="Post"/>
</form>使用XSRF在AJAX中
function getCookie(name) {
var r = document.cookie.match("\\b" + name + "=([^;]*)\\b");
return r ? r[1] : undefined;
}
jQuery.postJSON = function(url, args, callback) {
args._xsrf = getCookie("_xsrf");
$.ajax({url: url, data: $.param(args), dataType: "text", type: "POST",
success: function(response) {
callback(eval("(" + response + ")"));
}});
};启动服务
def main(): app = make_app() app.listen(8888) IOLoop.current().start()if __name__ == '__main__': main()
使用多核CPU
def main(): app = make_app() server = tornado.httpserver.HTTPServer(app) server.bind(8888) server.start(0) # forks one process per cpu IOLoop.current().start()
静态目录设置
settings = {
"": os.path.join(os.path.dirname(__file__), "static"),
"cookie_secret": "__TODO:_GENERATE_YOUR_OWN_RANDOM_VALUE_HERE__",
"login_url": "/login",
"xsrf_cookies": True,}
application = tornado.web.Application([
(r"/", MainHandler),
(r"/login", LoginHandler),
(r"/(apple-touch-icon\.png)", tornado.web.StaticFileHandler,
dict(path=settings['static_path'])),], **settings)嵌入到WSGI容器运行
嵌入到WSGI容器后，只可以运行tornado的一个子集功能，不支持异步操作，包括协程、@asynchronous装饰器、AsyncHTTPClient, the auth module, and WebSockets.
import tornado.webimport tornado.wsgiclass MainHandler(tornado.web.RequestHandler):
def get(self):
self.write("Hello, world")tornado_app = tornado.web.Application([
(r"/", MainHandler),])application = tornado.wsgi.WSGIAdapter(tornado_app)