[WORKAROUND] Setting up a REDIS cluster in pipeline

Drone Support
1

I am trying to setup a REDIS cluster as part of my drone 0.8 pipeline. I am working with cpapidas/docker-compose-redis-cluster (https://github.com/cpapidas/docker-compose-redis-cluster/blob/master/README.md). From the research I did, it seems REDIS requires IP addresses rather than hostnames when setting up the cluster. I tried assigning static IPs via a custom network and overriding the ‘drone_default’ network, but I couldn’t get either to work. Is there a way to assign static IPs to the REDIS nodes or dynamically retrieving the IP addresses from the nodes during pipeline execution? if so, could you please provide pointers? thanks!

2

There is a working example a redis configuration in the documentation:
http://docs.drone.io/redis-example/

I have pasted it below for convenience. Note that it works with hostnames and does not require static IP address. Hope that helps you get started.

pipeline:
  build:
    image: redis
    commands:
      - redis-cli -h redis ping
      - redis-cli -h redis set FOO bar
      - redis-cli -h redis get FOO

services:
  redis:
    image: redis
3

edit: sorry, I just realized that you are looking to create a redis cluster as opposed to a single redis instance. It is not currently possible to assign static IP addresses to containers.

4

Thanks very much for the quick reply, @bradrydzewski. I appreciate it.
I will try getting the IPs of the REDIS nodes at runtime to use as input to start the cluster; I will post results. In the meantime, is there an active feature request for enabling static IPs in drone pipelines?

5

Workaround

REDIS cluster solution: https://github.com/cpapidas/docker-compose-redis-cluster

The REDIS cluster solution I am working with creates a custom network and assigns static IPs to cluster nodes in drone.yml. It then hardcodes the node IPs in the REDIS cluster startup script. I removed the custom network and static IPs; I retrieve the nodes’ IP addresses at runtime and then set an environment variable for each node (all of this is done in drone.yml). Last, I updated the startup script to use the environment variables instead of the hard-coded IPs.

.drone.yml:

<snip/>

rediscluster:
  image: my-redis-cluster
  pull: true
  detach: true
  commands:
    - export REDIS1=$(getent hosts redis1 | awk '{print $1}'):7000
    - export REDIS2=$(getent hosts redis2 | awk '{print $1}'):7001
    - export REDIS3=$(getent hosts redis3 | awk '{print $1}'):7002
    - /docker-entrypoint.sh redis-cluster

REDIS cluster start-up script:

ruby /redis/src/redis-trib.rb create --replicas 0 $REDIS1 $REDIS2 $REDIS3

Hope this helps someone! Thanks!

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