ktmpl

ktmpl is a tool for processing Kubernetes manifest templates. It is a very simple client-side implementation of the Templates + Parameterization proposal.

Synopsis

ktmpl 0.5.0
Produces a Kubernetes manifest from a parameterized template

USAGE:
    ktmpl [OPTIONS] <template>

FLAGS:
    -h, --help       Prints help information
    -V, --version    Prints version information

OPTIONS:
    -b, --base64-parameter <NAME> <VALUE>
        Same as --parameter, but for values already encoded in Base64
    -p, --parameter <NAME> <VALUE>
        Supplies a value for the named parameter

ARGS:
    <template>    Path to the template file to be processed (use "-" to read from stdin)

Usage

Run ktmpl TEMPLATE where TEMPLATE is a path to a Kubernetes manifest template in YAML format. The included example.yml is a working example template.

To provide values for template parameters, use the --parameter option to supply key-value pairs. Using the provided example.yml, this would mean:

ktmpl example.yml --parameter MONGODB_PASSWORD secret

Template parameters that have default values can be overridden with the same mechanism:

ktmpl example.yml --parameter MONGODB_USER carl --parameter MONGODB_PASSWORD secret

The processed template will be output to stdout, suitable for piping into a kubectl command:

ktmpl example.yml --parameter MONGODB_PASSWORD password | kubectl create -f -

If a parameter's parameterType is base64, the value passed for that parameter via --parameter will be Base64-encoded before being inserted into the template. If the value passed via --parameter is already Base64-encoded, and hence encoding it again would be an error, use the --base64-parameter option instead:

ktmpl example.yml --base64-parameter MONGODB_PASSWORD c2VjcmV0 | kubectl create -f -

This can be handy when working with Kubernetes secrets, or anywhere else binary or opaque data is needed.

It's also possible to supply the template via stdin instead of a named file by using - as the filename:

cat example.yml | ktmpl - --parameter MONGODB_PASSWORD password | kubectl create -f -

Installing ktmpl

Cargo

cargo install ktmpl

Precompiled binary

Releases

Docker

docker pull inquicker/ktmpl

Building from source

1. Install the appropriate version of Rust for your system.
2. Run git clone [email protected]:InQuicker/ktmpl.git.
3. Inside the freshly cloned repository, run cargo install --path ..

Make sure Cargo's bin directory is added to your PATH environment variable.

Development

To package the current release for distribution, update TAG in the Makefile and then run make. Release artifacts will be written to the dist directory. Your GPG secret key will be required to sign sha256sums.txt.

Docker images for inquicker/ktmpl and inquicker/ktmpl:$TAG will be created, but you must push them manually. cargo publish must be run manually to release to crates.io.

Legal

ktmpl is released under the MIT license. See LICENSE for details.