Can't load .env variables into .conf

[jwise-mfg]

This line generates the .conf from the template, but doesn't seem to load any of the sourced .env variables -- nginx -t reports them as invalid...

# Fill your config options into nginx.conf.template to create nginx.conf
envsubst \
    "$(printf '${%s} ' $(bash -c "compgen -A variable"))"\
    < "$CONFIG_DIR/nginx.conf.template" \
    > "$CONFIG_DIR/nginx.conf"

[pirate]

I'd just do it by hand, there arent too many variables it actually uses in the template, and this was just a convenience suggestion I provided to autofill them (didn't test it myself).

[jwise-mfg]

I am trying that, through trial and error, but an example of what it should look like would help a lot. I've successfully added a few like this at the top of the .conf file:
env PROJECT_DIR=/opt/wiki;
Where the variable value is an uninterrupted string. But variables like this throw errors:
env CACHE_REQUESTS=GET HEAD POST;
Error is:

nginx: [emerg] invalid number of arguments in "env" directive in /etc/nginx/nginx.conf:23
nginx: configuration file /etc/nginx/nginx.conf test failed

[jwise-mfg]

If leave out the troublesome variables, I get further validation errors like:

invalid max_size value "max_size=$CACHE_SIZE" in /etc/nginx/nginx.conf:114
nginx: configuration file /etc/nginx/nginx.conf test failed

Where my env line looks like: env CACHE_SIZE=1GB;

[pirate]

I recommend following nginx docs to resolve any individual issues with nginx config keys: https://www.nginx.com/blog/nginx-caching-guide/

As mentioned in those docs, the format for that config key is max_size=10g not max_size=10GB.