I like being able to customize the docker image itself - but I realize this thread is more about “API” for the stock image.
Environment is nice. Probably we need a way to set custom spark config (as a file??) ________________________________ From: Holden Karau <hol...@pigscanfly.ca> Sent: Wednesday, March 21, 2018 10:44:20 PM To: Erik Erlandson Cc: dev Subject: Re: Toward an "API" for spark images used by the Kubernetes back-end I’m glad this discussion is happening on dev@ :) Personally I like customizing with shell env variables during rolling my own image, but definitely documentation the expectations/usage of the variables is needed before we can really call it an API. On the related question I suspect two of the more “common” likely customizations is adding additional jars for bootstrapping fetching from a DFS & also similarity complicated Python dependencies (although given the Pythons support isn’t merged yet it’s hard to say what exactly this would look like). I could also see some vendors wanting to add some bootstrap/setup scripts to fetch keys or other things. What other ways do folks foresee customizing their Spark docker containers? On Wed, Mar 21, 2018 at 5:04 PM Erik Erlandson <eerla...@redhat.com<mailto:eerla...@redhat.com>> wrote: During the review of the recent PR to remove use of the init_container from kube pods as created by the Kubernetes back-end, the topic of documenting the "API" for these container images also came up. What information does the back-end provide to these containers? In what form? What assumptions does the back-end make about the structure of these containers? This information is important in a scenario where a user wants to create custom images, particularly if these are not based on the reference dockerfiles. A related topic is deciding what such an API should look like. For example, early incarnations were based more purely on environment variables, which could have advantages in terms of an API that is easy to describe in a document. If we document the current API, should we annotate it as Experimental? If not, does that effectively freeze the API? We are interested in community input about possible customization use cases and opinions on possible API designs! Cheers, Erik -- Twitter: https://twitter.com/holdenkarau
