Internal server error running Django on Heroku accessing from browser - django

I think this is a simple fix, but I've deployed quite a few Django apps to Heroku and I still can't figure out what's going on.
Accessing https://dundjeon-finder.herokuapp.com/ gives me a 500 error when using the browser/curl, but if I shell into the app using heroku run ./manage.py shell I can render the views no problem. My logs aren't telling me anything (just that the response is 500) despite DEBUG being set to True, and Sentry isn't receiving an error (it has previously when the database env variable was set badly), so I'm assuming it's something to do with the way the request works.
The repo is public, any help would be much appreciated! The settings file is here.

Well it was because of using asgi instead of wsgi. I'm not sure why that caused the errors, but will do some more searching.

Related

Gunicorn + Flask - #app.errorhandler(500) being ignored?

I've spent quite a bit of time searching and I'm amazed I've not found an answer to this.
I've got basic #app.errorhandler(500) code in my flask app. As expected, I get a debugger when running with DEBUG on, and I get my custom error page when it's false. The next stage of my build though is serving the app from gunicorn in a docker container, and I'm just getting generic "Internal Server Error"s when I do that. I'm guessing gunicorn is handling the errors now instead of flask? But I can't for the life of me figure out how to ask it to let flask handle the errors (if that's even possible), or make it use custom error pages.
The final stage will be gunicorn in docker behind nginx, but I think I've found a config directive for nginx to make it let gunicorn handle the errors - I just need to get gunicorn to pass it down one level further so I can use my custom error page, and fire off notifications to relevant people with details regarding the error that occurred (which I suspect I'd lose if I did a custom error page at the gunicorn or nginx level). Help would be GREATLY appreciated.
I have Flask + gunicorn + Nginx system, The Internal Server Error was handled by default with Nginx, I added the following config to let 500 errors handled by flask:
import logging
from werkzeug.exceptions import InternalServerError
import traceback
#app.errorhandler(InternalServerError)
def handle_500(e):
logging.error(traceback.format_exc())
I was able to fix it with the below handle. But I still can't properly explain it. In any case even though the original handling (#app.app_errorhandler(500)) worked fine with the dev flask server and not with gunicorn, I don't believe the problem is to be solved with gunicron. It needs to be solved within the code.
#app.app_errorhandler(Exception)
def handle_exception_error(err):
""" Defines how to handle Exception errors. """
logger.error(err)
return "INTERNAL_SERVER_ERROR", 500

Graphite Web Error Log, OperationalError: no such table: auth_user

I have a problem with starting graphite web interface, using apache2. I get 500 Internal error, the screenshot of my log is below. I am new to this website and also to this software. My question might be too simple but, I have spent a lot of time on this. Thanks..
error log:
It looks like the database has not yet been created. You can do so by running:
sudo -u _graphite graphite-manage syncdb --noinput
and that should clear up the 500 error. This is a minimum to get started with Graphite, using the SQLite database. It is possible to configure an alternate database in the local_settings.py file, in which case the above command is not necessary. But with the default configuration, which uses SQLite as the back-end, this command should get you past the error.
Source: https://ianunruh.com/2014/05/monitor-everything-part-4.html

Heroku Server 500 error on particular page

Just deployed a Django app on Heroku. Everything works except for one page of my site which creates a Server 500 error (even though it works fine on my local development server).
The page raising the error doesn't do anything unusual. It makes some database calls, renders some forms, implements JQuery, etc. Any clue what this could be or how I can debug it?
Also, I thought this might be a data issue since my data in Dev doesn't match my data in production, but I checked and this doesn't seem to be the cause.
enable DEBUG=TRUE in your django settings.py file or type in console heroku logs --app your_app to get heroku server logs.
This was because I didn't include a runtime.txt telling Heroku to use Python 3 instead of 2 which subsequently raised an error in one of my views where I called super() with no args.

Django is giving me a 404 error

I installed Django, and it works. I set it up so it uses my mysql database, and I started a project. So far so good.
I followed the tutorial on setting up your first Django app over at
https://docs.djangoproject.com/en/dev/intro/tutorial01/
It is a tutorial over setting up a pre-existing poll app where everything has practically been built for you. The database structure has even been handled.
I ran:
python manage.py startapp polls
python manage.py sql polls
python manage.py syncdb
I didn't receive any kind of success message so I went into my phpmyadmin, and hooray! There are new tables and rows in my database.
Their tutorial then told me to run:
python manage.py shell
and that I'd see some database stuff, but I didn't. Why could this be? I ignored it and went on to step two. I still hadn't set DEBUG in my settings.py to False so I did. Only to get a 500 error.
After some digging I read I needed to add:
ALLOWED_HOSTS = ['my ip address'];
I did this and now after running:
python manage.py runserver myip:8000
When I try to access Django in my browser I get a
Not Found
The requested URL / was not found on this server.
Obviously / changes to a different location when navigating to those places as well, but the point is I get a 404 no matter what.
So I look at my terminal and I have a yellow message in my terminal that says.
"GET / HTTP/1.1" 404 74
and there is 1 message like this for each place I tried to access.
I'm thinking there is a Python package that I don't have installed on my server?
I do not want to use ALLOWED_HOSTS ['*'] I read that this is bad practice. I did try it and it produces the same results as using my ip address in place of the * (I just wanted to add that extra piece of info in case it helps)
If you want to use the database shell, you should run the dbshell command instead of shell as in your post, like this:
python manage.py dbshell
If you run shell, you get a Python shell, where you can easily import and inspect the Python objects of your project.
On your local PC, it's better to have DEBUG = True in your settings.py. That way you don't need to bother about ALLOWED_HOSTS, because in debug mode all hosts are allowed. Secondly, when you get a 404 error in debug mode, the page will show you the valid URLs that you can try.
The Django tutorial certainly works. The only way it won't work for you is if you missed a step or mistyped something somewhere. If you start over and pay extra attention, I think it will work.

Issue with Heroku, configuration variables and django using S3

I'm having a very strange issue.
I have my django project running in Heroku using S3 to store my static assets.
I wanted to use the Heroku enviroment variables by setting them as follows:
heroku config:add AWS_S3_TOKEN=my_s3_token
heroku config:add AWS_S3_SECRET=my_s3_secret
And using them with python's os module:
import os
token = os.getenv('AWS_S3_TOKEN')
secret = os.getenv('AWS_S3_SECRET')
But heroku keeps throwing me the following error:
NoAuthHandlerFound: No handler was ready to authenticate. 1 handlers were checked. ['HmacAuthV1Handler'] Check your credentials
So, I ended up writing those parameters in my settings.py file and it works fine
Why is this happening?
If I run
heroku config
I can see all my seted variables and if i do
heroku run python manage.py shell
and then
import os
print os.getenv('AWS_S3_TOKEN')
For example, it prints the variable's value.
any clue on this???
Thank you in advance
I'm not familiar with python or Django, but I'm curious.
If you try your authentication with blank strings, do you get the same error?
If so, then I suspect it's about when you're doing this authentication dance. When are you doing it? At compile time, or at runtime? (If at compile time, look at this)
The app's environment variables aren't usually available while Heroku is compiling the slug and setting up the application, they're only available once the app is running. For a Django app, Heroku will run collectstatic as part of slug compilation, which is probably why you're seeing this error.
You can make the environment variables available during compilation by enabling a Heroku Labs feature:
heroku labs:enable user-env-compile
There's more information in this Heroku dev centre article: https://devcenter.heroku.com/articles/labs-user-env-compile