Add option to not fail when region and prefix are not set

[nvllsvm]

I would like env-aws-params to run the target command as-is if the prefix and region are not set.

Conditions

• Neither the --aws-region flag nor the AWS_REGION environment variable are set.
• Neither the --prefix flag nor the PARAMS_PREFIX environment variable are set.

Current Behavior
Program aborts and does execute target command.

$ env-aws-params service
ERROR: prefix is required

Desired Behavior
Program warns of missing variables and executes target command without retrieving variables.

$ env-aws-params --ignore-no-config service
WARNING: SSM variables not set

Why
I'm conditionally using env-aws-params in a Docker entrypoint script to execute the Docker command as-is if neither the PARAMS_PREFIX and AWS_REGION variables are set. This allows me to use the same container in both production and a fully local environment; the container won't reach out to SSM unless both previous mentions env vars are set.

The entrypoint script is fairly generic as it only inspects variables used by env-aws-params. However, it ends up becoming a copy/paste snippet of code that gets carried around to multiple projects. It also must be an external file to be able to safely pass "$@" to it.

COPY entrypoint.sh /entrypoint.sh
ENTRYPOINT ["/entrypoint.sh"]

#!/usr/bin/env sh
if [ -n "${PARAMS_PREFIX}" ] && [ -n "${AWS_REGION}" ]; then
    exec env-aws-params "$@"
else
    exec "$@"
fi

Solution
Add a command-line flag to env-aws-params to do essentially the same thing.

ENTRYPOINT ["env-aws-params", "--ignore-no-config"]

I don't have a preference how this option is set; the name --ignore-no-config was picked without much thought put into it.

If you're open to including this, I'll glady take on development.