A small Docker image with the envsubst utility.
This may be useful as an initContainer for a Kubernetes deployment, to inject secrets into configuration files for applications that don't support reading them from the environment. See kubernetes/kubernetes#79224 for more.
The entrypoint of this image is /bin/sh -c.
$ docker run bfogarty/envsubst "envsubst --help"
Usage: envsubst [OPTION] [SHELL-FORMAT]
Substitutes the values of environment variables.
Operation mode:
-v, --variables output the variables occurring in SHELL-FORMAT
Informative output:
-h, --help display this help and exit
-V, --version output version information and exit
In normal operation mode, standard input is copied to standard output,
with references to environment variables of the form $VARIABLE or ${VARIABLE}
being replaced with the corresponding values. If a SHELL-FORMAT is given,
only those environment variables that are referenced in SHELL-FORMAT are
substituted; otherwise all environment variables references occurring in
standard input are substituted.
When --variables is used, standard input is ignored, and the output consists
of the environment variables that are referenced in SHELL-FORMAT, one per line.
Report bugs in the bug tracker at <https://savannah.gnu.org/projects/gettext>
or by email to <[email protected]>.
Content type
Image
Digest
Size
5.1 MB
Last updated
over 6 years ago
docker pull bfogarty/envsubst