envsubst-sh
envsubst-sh
Render config templates by substituting environment variables. A portable bash alternative to GNU envsubst with support for default values, required variables and custom delimiters.
Installation
bpkg install bashup/envsubst-sh
Usage
source bpkg_modules/envsubst-sh/envsubst.sh
# Render template to stdout
APP_PORT=3000 APP_NAME=myapp \
envsubst-sh template.conf.tmpl
# Write to file
envsubst-sh nginx.conf.tmpl > /etc/nginx/nginx.conf
# Fail if variable is unset
STRICT=1 envsubst-sh config.tmpl
Template syntax
server {
listen ${APP_PORT:-8080};
server_name ${APP_HOST}; # required
root ${APP_ROOT:-/var/www/html};
}
Default values
Use ${VAR:-default} for optional variables. With STRICT=1, any unset variable without a default causes an error and exit code 1.
Install
install envsubst-sh
Repository
License
MIT
Version
1.0.3
Category
Author
Dependencies
No explicit dependencies.
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