## DMITRY PROKOPTSEV ## Challenges when onboarding coroutines A lot of existing code mostly callback-based A custom-built I/O event loop predates Asio by a decade fine-tuned for specific use cases

get()/post()/etc) may be overridden as coroutines to make the handler asynchronous. Tornado also supports a callback-based style of asynchronous handler with the tornado.web.asynchronous decorator, but this style is signal that the stream has been closed while no other read or write is in progress. Unlike other callback-based interfaces, set_close_callback will not be removed in Tornado 6.0. BaseIOStream.closed() Returns a single generator instead of a collection of separate functions. For example, the following callback-based asynchronous handler: classAsyncHandler(RequestHandler): @asynchronous def get(self):

get()/post()/etc) may be overridden as coroutines to make the handler asynchronous. Tornado also supports a callback-based style of asynchronous handler with the tornado.web.asynchronous decorator, but this style is signal that the stream has been closed while no other read or write is in progress. Unlike other callback-based interfaces, set_close_callback will not be removed in Tornado 6.0. ### BaseIOStream.closed() a single generator instead of a collection of separate functions. For example, the following callback-based asynchronous handler: classAsyncHandler(RequestHandler): @asynchronous def get(self):

Deprecated since version 4.3: Use multi instead. #### tornado.gen.Task(func,*args,**kwargs) Adapts a callback-based asynchronous function for use in coroutines. Takes a function (and optional additional arguments) returned dictionary to make the result of get_authenticated_user. For backwards compatibility, the callback-based _oauth_get_user method is also supported. ## get auth http client() Returns the AsyncHTTPClient response self.assertIn("FriendFeed", response.body) # This test uses an explicit callback-based style. class MyTestCase3(AsyncTestCase): def test_http_fetch(self): client =AsyncHTTPClient(self

since version 4.3: Use multi instead. #### tornado.gen.Task(func, *args, **kwargs) Adapts a callback-based asynchronous function for use in coroutines. Takes a function (and optional additional arguments) returned dictionary to make the result of get_authenticated_user. For backwards compatibility, the callback-based _oauth_get_user method is also supported. ## get_auth_http_client() Returns the AsyncHTTPClient response self.assertIn("FriendFeed", response.body) # This test uses an explicit callback-based style. class MyTestCase3(AsyncTestCase): def test_http_fetch(self): client =AsyncHTTPClient(self

signal that the stream has been closed while no other read or write is in progress. Unlike other callback-based interfaces, set_close_callback was not removed in Tornado 6.0. BaseIOStream.closed() → bool for links to asynchronous libraries that may be useful. 2. Find a callback-based equivalent. Similar to the first option, callback-based libraries are available for many tasks, although they are slightly slightly more complicated to use than a library designed for coroutines. Adapt the callback-based function into a future: class CoroutineTimeoutHandler(RequestHandler): async def get(self): io_loop

signal that the stream has been closed while no other read or write is in progress. Unlike other callback-based interfaces, set_close_callback was not removed in Tornado 6.0. BaseIOStream.closed() → bool for links to asynchronous libraries that may be useful. 2. Find a callback-based equivalent. Similar to the first option, callback-based libraries are available for many tasks, although they are slightly slightly more complicated to use than a library designed for coroutines. Adapt the callback-based function into a future: class CoroutineTimeoutHandler(RequestHandler): async def get(self): io_loop

signal that the stream has been closed while no other read or write is in progress. Unlike other callback-based interfaces, set_close_callback was not removed in Tornado 6.0. BaseIOStream.closed() → bool for links to asynchronous libraries that may be useful. 2. Find a callback-based equivalent. Similar to the first option, callback-based libraries are available for many tasks, although they are slightly slightly more complicated to use than a library designed for coroutines. Adapt the callback-based function into a future: class CoroutineTimeoutHandler(RequestHandler): async def get(self): io_loop

signal that the stream has been closed while no other read or write is in progress. Unlike other callback-based interfaces, set_close_callback was not removed in Tornado 6.0. BaseIOStream.closed() → bool for links to asynchronous libraries that may be useful. 2. Find a callback-based equivalent. Similar to the first option, callback-based libraries are available for many tasks, although they are slightly slightly more complicated to use than a library designed for coroutines. Adapt the callback-based function into a future: class CoroutineTimeoutHandler(RequestHandler): async def get(self): io_loop

signal that the stream has been closed while no other read or write is in progress. Unlike other callback-based interfaces, set_close_callback was not removed in Tornado 6.0. BaseIOStream.closed() → bool for links to asynchronous libraries that may be useful. 2. Find a callback-based equivalent. Similar to the first option, callback-based libraries are available for many tasks, although they are slightly slightly more complicated to use than a library designed for coroutines. Adapt the callback-based function into a future: class CoroutineTimeoutHandler(RequestHandler): async def get(self): io_loop