Scripts and app template for Python applications

ppo

I created some scripts related to Python apps on Opalstack.

app-control: Control the operation of Python applications.
app-template-py: Convert a Python application created via the Control Panel using our app template.
py-install-version: Install a version of Python (in $HOME/opt).
py-versions: List available Python versions (in $PATH and $HOME/opt/bin).

Feedback welcomed 😀

sean

ppo Thanks for sharing this! ❤️

ppo

@sean Are the name and path of the virtual environment (env) and the pid file (tmp/uwsgi.pid or tmp/APP_NAME.pid) important (i.e. must remain the same)? For example because they are used in external configuration or scripts.

I noticed the start script is used in cron jobs.

sean

ppo nope, you can name them whatever you want. If you change something be sure to adjust whatever config, cron jobs, etc to match.

ppo

@dcd Thanks. Answering here is more appropriate 😉

app-template-py script works great - thanks!! Looks like it's only configured for python template though -- messes with the django app template (removes uwsgi, start, stop, etc.) Thanks a ton for coding this up -- huge time saver.

app-template-py moves all existing files into a sub-directory (mv * .* .original-files) and copies all files from my template.

Opalstack's installer for Django apps just create a base project using django-admin startproject myproject… which IMHO is a bit useless so I used the same for both Python/uWSGI and Django apps.

I added (here) the following to explain how to create a default Django app.

To create a Django application, you can start with the following…
(replace APP_NAME, MY_PROJECT, and your-domain.com with your values)

cd $HOME/apps/APP_NAME/

. venv/bin/activate
pip install django

cd tmp
django-admin startproject MY_PROJECT
mv MY_PROJECT/* ../app/
rmdir MY_PROJECT
cd ..

sed -i "s/ALLOWED_HOSTS = \[\]/ALLOWED_HOSTS = ['your-domain.com']/" app/MY_PROJECT/settings.py
sed -i "/DATABASES =/, /^}/ s/^/# /" app/MY_PROJECT/settings.py
sed -i "s#config/wsgi.\py#MY_PROJECT/wsgi.py#g" uwsgi.ini

app-control APP_NAME restart

# Fine-tuning ;-)
cd venv/bin/
rm django-admin.py
ln -s ../../app/manage.py
cd ../..

And you should see the default "The install worked successfully! Congratulations!" page on http://your-domain.com/

ppo

@sean I saw in the API request when creating a Python app that you send an installer_url parameter (getting the code from a public URL)… Does that mean we can provide our own installer? 😁

installer_url: "https://raw.githubusercontent.com/opalstack/installers/master/core/uwsgi/install.sh"

sean

ppo yes, app/add can take an installer_url argument.

The file available at installer_url needs to be an executable that takes the following arguments:

-i - the UUID of the new application
-t - your API token

When you make the API call the following things will happen:

The app will be created in our main database
The app directory will be created on the server
The file at installer_url will be downloaded and run as the app's shell user with the -i and -u arguments populated automatically.

What the install script does is up to you! Typically it goes like this:

Makes a call to app/read to get all of the details for the app.
Download and extract some archive of whatever software (or do pip install etc) in the app directory
Create a database if it's needed
Generate the config for the app
Create a cron job if it's needed

Our installer repo is public so feel free to look there for some examples: https://github.com/opalstack/installers

Most of our install scripts are written in Python or bash, but you can use whatever you want.

⚠️⚠️⚠️ Always verify that the script at installer_url is safe to run as your shell user before you include it in an API call.