Dokku + tornado app = 502 Bad Gateway

Question

I'm trying to make friends with dokku. I'm run dokku on DigitalOcean droplet.

user@mypc:~$ cat Procfile 
web: python3 main.py

user@mypc:~$ git push dokku master
Counting objects: 5, done.
Delta compression using up to 4 threads.
Compressing objects: 100% (3/3), done.
Writing objects: 100% (3/3), 295 bytes | 0 bytes/s, done.
Total 3 (delta 2), reused 0 (delta 0)
-----> Building app ...
-----> Installing ENV in build environment ...
   Python app detected
-----> Preparing Python runtime (python-3.4.0)
-----> Installing Setuptools (2.1)
-----> Installing Pip (1.5.4)
-----> Installing dependencies using Pip (1.5.4)
    < LONG INSTALL REQS LOG >
   Cleaning up...
-----> Discovering process types
   Procfile declares types -> web
-----> Releasing app ...
-----> Deploying app ...
-----> Cleaning up ...
=====> Application deployed:
   http://app.myapp.ru

To dokku@myapp.ru:app
   d2cd6b3..7733adf  master -> master

Despite the fact that the download is successful, I'm still getting 502 error

root@myserver:~# dokku run app ps aux
USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
root         1  0.0  0.2  17888  1496 ?        Ss+  08:41   0:00 /bin/bash /exec ps aux
root        13  0.0  0.2  15536  1128 ?        R+   08:41   0:00 ps aux

root@myserver:~# dokku logs app
[I 140324 08:41:37 main:75] Starting http server on localhost:5000

If you run the application directly, it successfully startanet, but I'll still get 502 error.

root@myserver:~# dokku run app python3 main.py
[I 140324 08:59:19 main:75] Starting http server on localhost:5000

All environment variables spelled correctly, and the like as the application is running. Any ideas?

Answer 1

Much easier than I thought. I had bind on 0.0.0.0

Sorry for stupid question.

Answer 2

I ran into this same problem. Binding to 0.0.0.0 was part of the problem. Dokku is also expecting Tornado to serve on port 5000. So, the fix was changing the server listen call to this: http_server.listen(5000, address='0.0.0.0')