Explain how to customize Postgres container images

[gbartolini]

Explain how to fork the postgres-containers project and how to build custom images with additional layers, including nightly builds through Github actions.

[mymasse]

We would be interested in this also, we're trying to build the Oracle Foreign Data wrapper extension into the image and when we try to launch a cluster with the new image it fails. We can't figure out why

[smiyc]

@sxd wrote an blog post about this topic

https://cloudnative-pg.io/blog/creating-container-images/

[jmealo]

I would be interested in picking this up.

[ardentperf]

@sxd wrote an blog post about this topic

https://cloudnative-pg.io/blog/creating-container-images/

nice blog! i kept a few notes from some of my own recent adventures and posted them at #115 (comment)

i noticed that this blog walked through creating a container layered on top of the CNPG containers. my notes walked through forking the CNPG postgres-containers repo itself and adding an extension from PGDG debian repo for all builds supported by CNPG postgres-containers and publishing results to github container registry via my forked repo - slightly different approach