else the user’s browser will simply hang. Here is an example that makes a call to the FriendFeed API using Tornado’s built-in AsyncHTTPClient: class MainHandler(tornado.web.RequestHandler): @tornado get(self): http = tornado.httpclient.AsyncHTTPClient() http.fetch("http://friendfeed-api.com/v2/feed/bret", callback=self.on_response) def on_response(self, response): write("Fetched " + str(len(json["entries"])) + " entries " "from the FriendFeed API") self.finish() When get() returns, the request has not finished. When the HTTP client eventually

else the user’s browser will simply hang. Here is an example that makes a call to the FriendFeed API using Tornado’s built-in AsyncHTTPClient: class MainHandler(tornado.web.RequestHandler): @tornado asynchronous def get(self): http = tornado.httpclient.AsyncHTTPClient() http.fetch("http://friendfeed-api.com/v2/feed/bret", callback=self.on_response) def on_response(self, response): if response.error: json_decode(response.body) self.write("Fetched " + str(len(json["entries"])) + " entries " "from the FriendFeed API") self.finish() When get() returns, the request has not finished. When the HTTP client eventually

fetch("http://friendfeed-api.com/v2/feed/bret") json = tornado.escape.json_decode(response.body) self.write("Fetched " + str(len(json["entries"])) + " entries " "from the FriendFeed API") For a more advanced per-handler basis, you can override RequestHandler. check_xsrf_cookie(). For example, if you have an API whose authentication does not use cookies, you may want to disable XSRF protection by making check_xsrf_cookie() 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. Template settings:

fetch("http://friendfeed-api.com/v2/feed/bret") json = tornado.escape.json_decode(response.body) self.write("Fetched " + str(len(json["entries"])) + " entries " "from the FriendFeed API") For a more advanced per-handler basis, you can override RequestHandler. check_xsrf_cookie(). For example, if you have an API whose authentication does not use cookies, you may want to disable XSRF protection by making check_xsrf_cookie() 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. Template settings:

fetch("http://friendfeed-api.com/v2/feed/bret") json = tornado.escape.json_decode(response.body) self.write("Fetched " + str(len(json["entries"])) + " entries " "from the FriendFeed API") 26 Chapter 6. Documentation per-handler basis, you can override RequestHandler. check_xsrf_cookie(). For example, if you have an API whose authentication does not use cookies, you may want to disable XSRF protection by making check_xsrf_cookie() 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. Template settings:

fetch("http://friendfeed-api.com/v2/feed/bret") json = tornado.escape.json_decode(response.body) self.write("Fetched " + str(len(json["entries"])) + " entries " "from the FriendFeed API") 26 Chapter 6. Documentation per-handler basis, you can override RequestHandler. check_xsrf_cookie(). For example, if you have an API whose authentication does not use cookies, you may want to disable XSRF protection by making check_xsrf_cookie() 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. Template settings:

fetch("http://friendfeed-api.com/v2/feed/bret") json = tornado.escape.json_decode(response.body) self.write("Fetched " + str(len(json["entries"])) + " entries " "from the FriendFeed API") 26 Chapter 6. Documentation per-handler basis, you can override RequestHandler. check_xsrf_cookie(). For example, if you have an API whose authentication does not use cookies, you may want to disable XSRF protection by making check_xsrf_cookie() 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. Template settings:

- api.com/v2/feed/bret") json = tornado.escape.json_decode(response.body) self.write("Fetched " + str(len(json["entries"])) + " entries " "from the FriendFeed API") For per-handler basis, you can override RequestHandler.check_xsrf_cookie(). For example, if you have an API whose authentication does not use cookies, you may want to disable XSRF protection by making check_xsrf_cookie() 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. Template settings:

fetch("http://friendfeed-api.com/v2/feed/bret") json = tornado.escape.json_decode(response.body) self.write("Fetched " + str(len(json["entries"])) + " entries " "from the FriendFeed API") 26 Chapter 6. DocumentationTornado per-handler basis, you can override RequestHandler. check_xsrf_cookie(). For example, if you have an API whose authentication does not use cookies, you may want to disable XSRF protection by making check_xsrf_cookie() 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. Template settings:

- api.com/v2/feed/bret") json = tornado.escape.json_decode(response.body) self.write("Fetched " + str(len(json["entries"])) + " entries " "from the FriendFeed API") For per-handler basis, you can override RequestHandler.check_xsrf_cookie(). For example, if you have an API whose authentication does not use cookies, you may want to disable XSRF protection by making check_xsrf_cookie() 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. Template settings: