https://github.com/zeroXten/consul-do

Do something based on leadership status
https://github.com/zeroXten/consul-do

Last synced: 2 months ago
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Do something based on leadership status

• Host: GitHub
• URL: https://github.com/zeroXten/consul-do
• Owner: zeroXten
• License: mit
• Created: 2014-12-22T13:17:38.000Z (about 10 years ago)
• Default Branch: master
• Last Pushed: 2023-07-11T07:59:20.000Z (over 1 year ago)
• Last Synced: 2024-08-03T02:05:11.220Z (5 months ago)
• Language: Python
• Size: 9.77 KB
• Stars: 58
• Watchers: 9
• Forks: 11
• Open Issues: 3
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

Awesome Lists containing this project

• awesome-consul - consul-do: Do something based on leadership status

README

        
consul-do

=========

Do something based on leadership status using consul.io

See https://consul.io

Installation

============

It's just a python script with no additional modules. Download it and stick it somewhere.  

*NOTE* A consul agent is required to be installed where you run this script.

Usage

=====

    $ consul-do

    Usage: consul-do KEY [DEBUG]

Useful for running cronjobs in HA mode.

Run something like this on two or more servers:

    *    * * * * /usr/bin/consul-do JOB-1 && /path/to/job1

    */10 * * * * /usr/bin/consul-do JOB-2 && /path/to/job2

Only one of the servers will be elected leader and will therefore run the job. Should the leader fail, a follower will take over.

To enable debug mode, add anything as a second argument. E.g.

    $ consul-do JOB-1 debug

    Running...

    Found nodename: test.internal

    Found KV store

    Found session: e32c055d-c6ed-e277-45ad-079ba218bb01

    Found session node, we're the leader

    ....

If you require a consul ACL

    $ CONSUL_HTTP_TOKEN="mytoken" consul-do ... 

Testing

=======

    $ vagrant up

Run the following on each respective server

    $ consul agent -server -bootstrap-expect 1 -data-dir /tmp/consul -node=agent-one -bind=172.20.20.10

    $ consul agent -server -join 172.20.20.10 -data-dir /tmp/consul -node=agent-two -bind=172.20.20.11

    $ consul agent -server -join 172.20.20.10 -data-dir /tmp/consul -node=agent-three -bind=172.20.20.12

Now you can run a command on each server

    $ while true; do /vagrant/consul-do testing && date; sleep 10; done