kube

Kube integration

Want to run migrations as kubernetes jobs using automig so that you don't have to manually define up and down steps? You're in the right place.

The stuff in this folder should guide you through attaching automig to your git repo & kube cluster.

This is a beta

Bear in mind:

1. Warts are to be expected, raise issues if these docs are incomplete / unclear / wrong
2. That being said, such support is not guaranteed
3. Loss of data or undesired extra data are among the many possible bad outcomes of using this

Documentation

Prerequisites

1. Be familiar with kustomize (the kube-native helm replacement)
2. Be using postgres -- the toolchain will need some tweaks to work with mysql

Initial setup

1. Set up your repo to build a docker image for migration
   • add automig.Dockerfile to your project repo (it's named that way to avoid colliding with your existing Dockerfile)
   • edit the COPY schema schema/ line in automig.Dockerfile to the folder where you store your SQL schema file(s)
   • update your CI spec to write to your container registry (there's a sample .gitlab-ci.yml in this folder)
2. Wire up kustomize
   • in theory this will work whether or not you're currently using kustomize, but no promises
   • in kustomization.yml, edit name and newTag to match your image name
   • in migrate.yml, edit image to match your image name
   • still in migrate.yml, update the names of the secrets to match what you're using
     • database-credentials is a secret that has a postgres connection string (postgres:// or whatever) in the libpq-url key
     • regcred has a dockerconfigjson for your container registry; you may not need this if your registry is integrated with your cloud host
3. in migrate.yml, update AUTOMIG_GLOB to whatever you're using
4. Run kustomize to apply this to your cluster, fix / report any errors

Running your initial migration

(Todo: add instructions for attaching automig to an existing database).

1. In migrate.yml, change update in the command to init
2. Run kustomize to apply this to your cluster
3. Run a copy of the migration job with: kubectl create job mig-$(shell whoami)-$(shell date -u +%Y%m%d-%H%M) --from=cronjob/migrate
4. Use kubectl get job and kubectl logs job/whatever -f to wait for success
5. Important: once this works, change init back to update and rerun kustomize

Running subsequent migrations

1. In kustomize.yml, change newTag to your desired sha
2. Run customize to apply this to your cluster
3. Run and watch the migration job with steps 3 & 4 above