tornado.web.Application類配置及使用

Application configuration

class tornado.web. Application (handlers=None, default_host='', transforms=None, **settings)[source]

A collection of request handlers that make up a web application.

Instances of this class are callable and can be passed directly to HTTPServer to serve the application:

application = web.Application([ (r"/", MainPageHandler), ]) http_server = httpserver.HTTPServer(application) http_server.listen(8080) ioloop.IOLoop.current().start() 

The constructor for this class takes in a list of URLSpec objects or (regexp, request_class) tuples. When we receive requests, we iterate over the list in order and instantiate an instance of the first request class whose regexp matches the request path. The request class can be specified as either a class object or a (fully-qualified) name.

Each tuple can contain additional elements, which correspond to the arguments to the URLSpecconstructor. (Prior to Tornado 3.2, only tuples of two or three elements were allowed).

A dictionary may be passed as the third element of the tuple, which will be used as keyword arguments to the handler’s constructor and initialize method. This pattern is used for theStaticFileHandler in this example (note that a StaticFileHandler can be installed automatically with the static_path setting described below):

application = web.Application([ (r"/static/(.*)", web.StaticFileHandler, {"path": "/var/www"}), ]) 

We support virtual hosts with the add_handlers method, which takes in a host regular expression as the first argument:

application.add_handlers(r"www\.myhost\.com", [ (r"/article/([0-9]+)", ArticleHandler), ]) 

You can serve static files by sending the static_path setting as a keyword argument. We will serve those files from the /static/ URI (this is configurable with the static_url_prefix setting), and we will serve /favicon.ico and /robots.txt from the same directory. A custom subclass ofStaticFileHandler can be specified with the static_handler_class setting.

settings

Additional keyword arguments passed to the constructor are saved in the settingsdictionary, and are often referred to in documentation as “application settings”. Settings are used to customize various aspects of Tornado (although in some cases richer customization is possible by overriding methods in a subclass of RequestHandler). Some applications also like to use the settings dictionary as a way to make application-specific settings available to handlers without using global variables. Settings used in Tornado are described below.

一般設置:

• autoreload: 如果設置 True,如果文件有變化進程將自動重啟, 在 Debug mode and automatic reloading（DeBug模式和自動裝載的情況下自動開啟）.
• debug: 幾種配置的集合, 具體查看 Debug mode and automatic reloading. 設置 debug=True 相當於設置 autoreload=True,compiled_template_cache=False, static_hash_cache=False, serve_traceback=True.
• default_handler_class and default_handler_args: 在頁面沒有找到（404錯誤的時候）自定義404錯誤頁視圖動作類及參數
• compress_response: 如果設置 True, responses（響應）將被自動壓縮
• gzip: 在Tornado 4.0被compress_response代替
• log_function: 這個函數用來回調 RequestHandler 對象的處理結果，默認主程序導入logging並配置好的話會自動記錄.也可以定制Application.log_request這個方法.
• serve_traceback: 如果設置 true,錯誤頁面將包含錯誤跟蹤
• ui_modules and ui_methods: 配置 UIModule 或 UI methods配置模版可用的幫助方法. 可以是一個模塊、字典或一個模塊或者字典的列表. 更多細節查看 UI modules

認證和安全設置:

• cookie_secret: 被 RequestHandler.get_secure_cookie和set_secure_cookie用來配置cookie的標志
• key_version: 被 set_secure_cookie 用來配置cookie的標志時cookie_secret的一個key
• login_url: 如果沒有用戶登錄這個 authenticated 裝飾器將被重新定義到. 可以進一步重寫 RequestHandler.get_login_url
• xsrf_cookies: If true, Cross-site request forgery protection will be enabled.
• xsrf_cookie_version: Controls the version of new XSRF cookies produced by this server. Should generally be left at the default (which will always be the highest supported version), but may be set to a lower value temporarily during version transitions. New in Tornado 3.2.2, which introduced XSRF cookie version 2.
• xsrf_cookie_kwargs: May be set to a dictionary of additional arguments to be passed toRequestHandler.set_cookie for the XSRF cookie.
• twitter_consumer_key, twitter_consumer_secret, friendfeed_consumer_key,friendfeed_consumer_secret, google_consumer_key, google_consumer_secret, facebook_api_key,facebook_secret: Used in the tornado.auth module to authenticate to various APIs.

模版設置:

• autoescape: 制對模板的自動轉義. 可以被設置為 None 以禁止轉義, 或設置為一個所有輸出都該傳遞過數 name . 默認是 "xhtml_escape". 可以在每個模板中改變使用 {% autoescape %} 指令.
• compiled_template_cache:  默認 True; 如果 False 每次請求將重新加載模版
• template_path: 模版文件目錄. 可以被 RequestHandler.get_template_path獲取進行重寫
• template_loader: 分配一個 tornado.template.BaseLoader進行模版加載.如果設置了template_path和 autoescape將失效. 可以被 RequestHandler.create_template_loader進一步重寫.
• template_whitespace: 對於模板中的空白處理; 詳細用法請看tornado.template.filter_whitespace

靜態文件設置:

• static_hash_cache: 默認 True; 如果 False 靜態 urls 將重新加載靜態文件
• static_path: 靜態文件的目錄
• static_url_prefix: 靜態文件的Url前綴, 默認為 "/static/".
• static_handler_class, static_handler_args: 可以自定義處理靜態文件的動作和參數，而不是默認的 tornado.web.StaticFileHandler. static_handler_args, 如果設置了，應該有一個字典被傳入到動作類的 initialize 方法中

listen (port, address='', **kwargs)[source]

Starts an HTTP server for this application on the given port.

This is a convenience alias for creating an HTTPServer object and calling its listen method. Keyword arguments not supported by HTTPServer.listen are passed to the HTTPServerconstructor. For advanced uses (e.g. multi-process mode), do not use this method; create anHTTPServer and call its TCPServer.bind/TCPServer.start methods directly.

Note that after calling this method you still need to call IOLoop.current().start() to start the server.

Returns the HTTPServer object.

Changed in version 4.3: Now returns the HTTPServer object.

add_handlers (host_pattern, host_handlers)[source]

Appends the given handlers to our handler list.

Host patterns are processed sequentially in the order they were added. All matching patterns will be considered.

reverse_url (name, *args)[source]

Returns a URL path for handler named name

The handler must be added to the application as a named URLSpec.

Args will be substituted for capturing groups in the URLSpec regex. They will be converted to strings if necessary, encoded as utf8, and url-escaped.

log_request (handler)[source]

Writes a completed HTTP request to the logs.

By default writes to the python root logger. To change this behavior either subclass Application and override this method, or pass a function in the application settings dictionary as log_function.