tornado – Page 2 – Tarik Billa

How to redirect on another page and pass parameter in url from table?

August 29, 2023 by Tarik

Set the user name as data-username attribute to the button and also a class: HTML <input type=”button” name=”theButton” value=”Detail” class=”btn” data-username=”{{result[‘username’]}}” /> JS $(document).on(‘click’, ‘.btn’, function() { var name = $(this).data(‘username’); if (name != undefined && name != null) { window.location = ‘/player_detail?username=” + name; } }); EDIT: Also, you can simply check for undefined … Read more

Why use Tornado and Flask together?

June 12, 2023 by Tarik

According to this question it is because Flask is blocking and Tornado is non-blocking. If one uses Tornado as a WSGI server and Flask for URL routing and templates (undocumented) there shouldn’t be any overhead. With this approach you aren’t using Flask’s web server, so there isn’t really an extra layer of abstraction. However, if … Read more

Tornado URL query parameters

May 30, 2023 by Tarik

There is a better way for GET requests. There is a demo in the tornado source on github here # url handler handlers = [(r”/entry/([^/]+)”, EntryHandler),] class EntryHandler(BaseHandler): def get(self, slug): entry = self.db.get(“SELECT * FROM entries WHERE slug = %s”, slug) if not entry: raise tornado.web.HTTPError(404) self.render(“entry.html”, entry=entry) Any “text” that matches the regular … Read more

How to get image size (bytes) using PIL

May 26, 2023 by Tarik

Try: import os print os.stat(‘somefile.ext’).st_size

How to best perform Multiprocessing within requests with the python Tornado server?

May 18, 2023 by Tarik

If you’re willing to use concurrent.futures.ProcessPoolExecutor instead of multiprocessing, this is actually very simple. Tornado’s ioloop already supports concurrent.futures.Future, so they’ll play nicely together out of the box. concurrent.futures is included in Python 3.2+, and has been backported to Python 2.x. Here’s an example: import time from concurrent.futures import ProcessPoolExecutor from tornado.ioloop import IOLoop from … Read more

tornado 403 GET warning when opening websocket

May 10, 2023 by Tarik

please add def check_origin(self, origin): return True in class MyHandler like this class MyHandler(tornado.websocket.WebSocketHandler): def check_origin(self, origin): return True def open(self): print “connection opened” self.write_message(“connection opened”) def on_close(self): print “connection closed” def on_message(self,message): print “Message received: {}”.format(message) self.write_message(“message received”) From the DOCs: By default, [check_origin] rejects all requests with an origin on a host other … Read more

using Flask and Tornado together?

April 8, 2023 by Tarik

i think i got 50% of the solution, the cookies are not tested yet, but now i can load Flask application using Tornado, and mixing Tornado + Flask together 🙂 first here is flasky.py the file where the flask application is: from flask import Flask app = Flask(__name__) @app.route(‘/flask’) def hello_world(): return ‘This comes from … Read more

Is Tornado a replacement to Django or are they complementary to each other?

April 5, 2023 by Tarik

To answer the question, NO, Tornado is not a replacement to Django. It’s an alternative. YES, they are complementary to each other but not in the same process (*) I would use Django when it’s a big team effort and/or needs to run on a SQL database. I would use Tornado for everything else. Ie. … Read more

How to make SQLAlchemy in Tornado to be async?

March 28, 2023 by Tarik

ORMs are poorly suited for explicit asynchronous programming, that is, where the programmer must produce explicit callbacks anytime something that uses network access occurs. A primary reason for this is that ORMs make extensive use of the lazy loading pattern, which is more or less incompatible with explicit async. Code that looks like this: user … Read more

Jupyter Notebook with Python 3.8 – NotImplementedError

February 9, 2023 by Tarik

EDIT This issue exists in older versions of Jupyter Notebook and was fixed in version 6.0.3 (released 2020-01-21). To upgrade to the latest version run: pip install notebook –upgrade Following on this issue through GitHub, it seems the problem is related to the tornado server that jupyter uses. For those that can’t wait for an … Read more