tornado has its own event loop which is incompatible with asyncio's event loop. But it can be solved.
First, create a BaseHandler extended from tornado.web.RequestHandler:
class BaseHandler(tornado.web.RequestHandler):
@staticmethod
def asyncio_task(method):
@functools.wraps(method)
async def wrapper(self, *args, **kwargs):
asyncio won't automatically create event loop for sub-thread, so to run async tasks in sub-thread, we need to manually create an event loop first.
loop = asyncio.new_event_loop()
asyncio.set_event_loop(loop)
asyncio.ensure_future(task())
loop.run_forever()
| function drawArray(arr) { | |
| /* | |
| Thanks original author @vukicevic | |
| Usage: | |
| Pass a two-dimensional arrary. | |
| The first dimonsion is rows, the second one is columns. | |
| Note that in columns, each pixel is represented by four nums as BGRA, so the columns' length is four times as image's length. | |
| return image's base64 code. | |
| */ |