kubecron

A simple kubernetes cron system

Description

A simple kubernetes cron system based on the google/cloud-sdk image. The main idea is to have a running pod, that will execute commands, and also have inside it the kubectl tools.

You can build periodic tasks that manage your app or your cluster.

• Every task is a shell script / program binary ... like (bin/show_pods.sh)
• Add scripts to cron.json
• The format for time is based on http://github.com/robfig/cron
• Every time you need to update the cron, just build a new container and update your rc.

Why

• More easy than configure a cron container
• Logs (stderr, stdout) are forwaded to console
• Tasks and cron are on source tree.

Howto

• Create your script and add them to bin
• Add the entry to cron.json, format:

{
  "cmd": "/bin/show_pods.sh",
  "when": "@every 2h"
}

• Install your cron on kubernetes (Must be done only the first time) Add your docker image to k8.yml and

make create_rc

check that the pod is present:

  kubectl get rc kubecron

• Update: Add your scripts, and run make update This will recreate your image, push it and do a rolling-update

• Develop: For recompiling, or changing the cron.go, you will need a go dev env, and source the init.sh first . (This will add src/tmpo.io to your GOPATH)

Improvements, feature plans an ideas.

Make the cron.json curl downloadable.. (on gcloud, s3... )

Contribute

Just fill up issues and make pull requests.