I'm preparing to use nginx/uwsgi with flask for a website i'm developing, but i'm running into problems. NB the website itself runs great using flask's debug :5000 port, but i want to go into production now. To explain what i did.
It's a linode ubuntu 12.04LTS server, I installed it like this:
# install nginx
sudo apt-get install python-software-properties
sudo add-apt-repository ppa:nginx/stable
sudo apt-get update
sudo apt-get upgrade --show-upgraded
sudo apt-get install nginx-full
# installing uwsgi
sudo apt-get install build-essential python-dev libxml2-dev
sudo apt-get install libc6 libexpat1 libgd2-xpm libgeoip1 libpam0g libpcre3 libssl1.0.0 libxml2 libxslt1.1 zlib1g
sudo pip install uwsgi
# python basics
sudo apt-get install python-pip build-essential python-dev
sudo pip install virtualenv
sudo pip install virtualenvwrapper
sudo mkdir -p /srv/www/li/
cd /srv/www/li/
virtualenv venv
source /srv/www/li/venv/bin/activate
pip install flask
Then i set out to configure everything, but I already run into trouble with uwsgi (never mind NGINX, which will be the next step.
sudo nano /etc/uwsgi/apps-available/li.xml
<uwsgi>
<plugin>python</plugin>
<socket>/run/uwsgi/app/li.socket</socket>
<chmod-socket>666</chmod-socket>
<chdir>/srv/www/li</chdir>
<pythonpath>/srv/www/li</pythonpath>
<virtualenv>/srv/www/li/venv</virtualenv>
<module>li</module>
<wsgi-file>/srv/www/li/li.py</wsgi-file>
<callable>app</callable>
<master/>
<processes>4</processes>
<harakiri>60</harakiri>
<reload-mercy>8</reload-mercy>
<cpu-affinity>1</cpu-affinity>
<stats>/tmp/stats.socket</stats>
<max-requests>2000</max-requests>
<limit-as>512</limit-as>
<reload-on-as>256</reload-on-as>
<reload-on-rss>192</reload-on-rss>
<no-orphans/>
<vacuum/>
</uwsgi>
sudo ln -s /etc/uwsgi/apps-available/li.xml /etc/uwsgi/apps-enabled/li.xml
However if i run it, i get:
uwsgi --xml /etc/uwsgi/apps-enabled/li.xml
[uWSGI] parsing config file /etc/uwsgi/apps-enabled/li.xml
open("./python_plugin.so"): No such file or directory [core/utils.c line 4755]
!!! UNABLE to load uWSGI plugin: ./python_plugin.so: cannot open shared object file: No such file or directory !!!
*** Starting uWSGI 1.4.6 (64bit) on [Thu Feb 28 16:30:53 2013] ***
compiled with version: 4.6.3 on 28 February 2013 12:38:22
os: Linux-3.7.10-x86_64-linode30 #1 SMP Wed Feb 27 14:29:31 EST 2013
nodename: demo
machine: x86_64
clock source: unix
detected number of CPU cores: 4
current working directory: /run/uwsgi/app
detected binary path: /usr/local/bin/uwsgi
your processes number limit is 63594
limiting address space of processes...
your process address space limit is 536870912 bytes (512 MB)
your memory page size is 4096 bytes
*** WARNING: you have enabled harakiri without post buffering. Slow upload could be rejected on post-unbuffered webservers ***
detected max file descriptor number: 1024
lock engine: pthread robust mutexes
uwsgi socket 0 bound to UNIX address /run/uwsgi/app/li.socket fd 3
Python version: 2.7.3 (default, Aug 1 2012, 05:25:23) [GCC 4.6.3]
Set PythonHome to /srv/www/li/venv
*** Python threads support is disabled. You can enable it with --enable-threads ***
Python main interpreter initialized at 0xa86e20
your server socket listen backlog is limited to 100 connections
mapped 362120 bytes (353 KB) for 4 cores
*** Operational MODE: preforking ***
added /srv/www/li/ to pythonpath.
/srv/www/li/venv/local/lib/python2.7/site-packages/mongoengine/fields.py:744: FutureWarning: ReferenceFields will default to using ObjectId strings in 0.8, set DBRef=True if this isn't desired
warnings.warn(msg, FutureWarning)
WSGI app 0 (mountpoint='') ready in 1 seconds on interpreter 0xa86e20 pid: 14934 (default app)
*** uWSGI is running in multiple interpreter mode ***
spawned uWSGI master process (pid: 14934)
spawned uWSGI worker 1 (pid: 14940, cores: 1)
mapping worker 1 to CPUs: 0
spawned uWSGI worker 2 (pid: 14941, cores: 1)
mapping worker 2 to CPUs: 1
spawned uWSGI worker 3 (pid: 14942, cores: 1)
mapping worker 3 to CPUs: 2
spawned uWSGI worker 4 (pid: 14943, cores: 1)
unlink(): Operation not permitted [core/socket.c line 109]
bind(): Address already in use [core/socket.c line 141]
...brutally killing workers...
mapping worker 4 to CPUs: 3
VACUUM: unix socket /run/uwsgi/app/li.socket removed.
So i get the unlink operation not permitted and the bind address already in use errors (next to the python_plugin error of which i also have no clue how to solve that!). If i run as sudo, it seems to work fine ->
sudo uwsgi --xml /etc/uwsgi/apps-enabled/li.xml
[uWSGI] parsing config file /etc/uwsgi/apps-enabled/li.xml
open("./python_plugin.so"): No such file or directory [core/utils.c line 4755]
!!! UNABLE to load uWSGI plugin: ./python_plugin.so: cannot open shared object file: No such file or directory !!!
*** Starting uWSGI 1.4.6 (64bit) on [Thu Feb 28 15:47:41 2013] ***
compiled with version: 4.6.3 on 28 February 2013 12:38:22
os: Linux-3.7.10-x86_64-linode30 #1 SMP Wed Feb 27 14:29:31 EST 2013
nodename: demo
machine: x86_64
clock source: unix
detected number of CPU cores: 4
current working directory: /run/uwsgi
detected binary path: /usr/local/bin/uwsgi
uWSGI running as root, you can use --uid/--gid/--chroot options
*** WARNING: you are running uWSGI as root !!! (use the --uid flag) ***
your processes number limit is 63594
limiting address space of processes...
your process address space limit is 536870912 bytes (512 MB)
your memory page size is 4096 bytes
*** WARNING: you have enabled harakiri without post buffering. Slow upload could be rejected on post-unbuffered webservers ***
detected max file descriptor number: 1024
lock engine: pthread robust mutexes
uwsgi socket 0 bound to UNIX address /run/uwsgi/app/li.socket fd 3
Python version: 2.7.3 (default, Aug 1 2012, 05:25:23) [GCC 4.6.3]
Set PythonHome to /srv/www/li/venv
*** Python threads support is disabled. You can enable it with --enable-threads ***
Python main interpreter initialized at 0x1fc9d00
your server socket listen backlog is limited to 100 connections
mapped 362120 bytes (353 KB) for 4 cores
*** Operational MODE: preforking ***
added /srv/www/li/ to pythonpath.
/srv/www/li/venv/local/lib/python2.7/site-packages/mongoengine/fields.py:744: FutureWarning: ReferenceFields will default to using ObjectId strings in 0.8, set DBRef=True if this isn't desired
warnings.warn(msg, FutureWarning)
WSGI app 0 (mountpoint='') ready in 0 seconds on interpreter 0x1fc9d00 pid: 14755 (default app)
*** uWSGI is running in multiple interpreter mode ***
spawned uWSGI master process (pid: 14755)
spawned uWSGI worker 1 (pid: 14761, cores: 1)
mapping worker 1 to CPUs: 0
spawned uWSGI worker 2 (pid: 14762, cores: 1)
mapping worker 2 to CPUs: 1
spawned uWSGI worker 3 (pid: 14763, cores: 1)
mapping worker 3 to CPUs: 2
spawned uWSGI worker 4 (pid: 14764, cores: 1)
*** Stats server enabled on /tmp/stats.socket fd: 16 ***
mapping worker 4 to CPUs: 3
Can anyone please help me? As www-data is in the www-data group and he runs it, I tried some stuff:
sudo usermod -a -G www-data $USER
sudo chown -R $USER:www-data /srv/www/li
sudo chmod -R g+r+w+x /srv/www/li
sudo chown -R $USER:www-data /etc/uwsgi/apps-enabled
sudo chmod -R g+r+w+x /etc/uwsgi/apps-enabled
sudo chown -R $USER:www-data /run/uwsgi/app
sudo chmod -R g+r+w+x /run/uwsgi/app
But that really didn't help either. I also tried a tcp port instead of the unix /run/uwsgi/app/ port that didn't make any difference either... This is driving me crazy :( I hope someone has a clue on what's happening here.
Kind regards,
Carst
edit: after a server restart it still gives an erro but a different one:
geoadmin@demo:~$ uwsgi --xml /etc/uwsgi/apps-enabled/li.xml
[uWSGI] parsing config file /etc/uwsgi/apps-enabled/li.xml
*** Starting uWSGI 1.4.6 (64bit) on [Thu Feb 28 18:47:36 2013] ***
compiled with version: 4.6.3 on 28 February 2013 12:38:22
os: Linux-3.7.10-x86_64-linode30 #1 SMP Wed Feb 27 14:29:31 EST 2013
nodename: demo
machine: x86_64
clock source: unix
detected number of CPU cores: 4
current working directory: /home/geoadmin
detected binary path: /usr/local/bin/uwsgi
your processes number limit is 63594
limiting address space of processes...
your process address space limit is 536870912 bytes (512 MB)
your memory page size is 4096 bytes
*** WARNING: you have enabled harakiri without post buffering. Slow upload could be rejected on post-unbuffered webservers ***
detected max file descriptor number: 1024
lock engine: pthread robust mutexes
bind(): No such file or directory [core/socket.c line 141]
Answer
This was consistently my #1 result on google, and this page was relatively unhelpful to me, so I'm going to add my answer, even though it's fairly obvious in retrospect.
My problem was a permissions problem with my stats socket. If you change your uWSGI config's uid or gid parameters, make sure you either chmod or rm all of your old sockets/ pids, and their parent folders.