Prevent automatic image building in kube play

[Korijn]

/kind feature

Description

In #11180 support was added to build images automatically in podman play kube.

However, this is undesirable if your images cannot be built without additional custom commands such as build secrets/arguments.

Our project's repository structure just happens to be organized according to the structure described the command's reference:

If there is a directory named foobar in the current working directory with a file
named Containerfile or Dockerfile, Podman play kube will build that image and name it foobar. 

So, if no prebuilt image is available, and can be pulled, podman still decides to try and build, and of course fail.

The only workaround is to manually pull the individual images beforehand, or build them manually. Annoying and time consuming!

This is on podman version 3.4.2.

I see a couple of options:

• Instead of building automatically, add a flag --build-missing to opt-in
• Add a flag to opt-out of automatic building --no-build

[Luap99]

I think you can use --build=false already

[Korijn]

I think you can use --build=false already

Really? I didn't realize the flag took an argument. I'll try.

[Luap99]

All bool flags can be used with =true|false
Looking at the code the default is already false so there is something wrong here if it builds without setting --build.

[Korijn]

(I haven't found time to try yet)

Well, in pkg/domain/infra/abi/play.go the following if statement is used:

if (len(buildFile) > 0 && !existsLocally) || (len(buildFile) > 0 && options.Build) {

That doesn't seem to really honor the --build=false case. Even if options.Build is false, the first part of the || statement will evaluate to true. That's what makes this "automatic", I suppose.

[flouthoc]

@Korijn I think above PR should close this. I think --build was meant to be true by default according to docs here https://github.com/containers/podman/blob/main/docs/source/markdown/podman-play-kube.1.md but I agree it should honor false value.

[Korijn]

Sure, thanks !