Fleet Templater

Fleet Templater is a simple program that will process Fleet unit files through a templating system.

In other words, you can take a file named myservice-{{env}}.service which contains the following content:

[Unit]
Description=myservice-{{env}}
Requires=docker.service
After=docker.service

[Service]
TimeoutStartSec=0
ExecStartPre=-/usr/bin/docker kill %p-%i
ExecStartPre=-/usr/bin/docker rm %p-%i
ExecStartPre=/usr/bin/docker pull myservice:{{env}}
ExecStart=/usr/bin/docker run -e ENV={{env}} myservice:{{env}}
ExecStop=/usr/bin/docker kill %p-%i

and then process it with env=production to produce myservice-production.service containing the following completed data:

[Unit]
Description=myservice-production
Requires=docker.service
After=docker.service

[Service]
TimeoutStartSec=0
ExecStartPre=-/usr/bin/docker kill %p-%i
ExecStartPre=-/usr/bin/docker rm %p-%i
ExecStartPre=/usr/bin/docker pull myservice:production
ExecStart=/usr/bin/docker run -e ENV=production myservice:production
ExecStop=/usr/bin/docker kill %p-%i

Installing and running with NodeJS

npm install -g node-templater
node-templater --help

node-templater test.service ./ myval=thing

Running as a docker container

docker pull yodlr/fleet-templater
docker run --rm -ti -v ${PWD}:/tmp fleet-templater /tmp/test.service /tmp/ myval=thing