Buildah doesn't skip stages in multi-stage Dockerfile

[lucacome]

Description

This is an example of a Dockerfile:

FROM golang as base


FROM base as foo
RUN echo "foo"

FROM base as local
COPY . /go/src/go-test/
RUN go build /go/src/go-test/main.go

Building with podman build --target local . I would expect to just build the stages that are needed for the local stage (and not the foo stage). Maybe I'm misunderstanding how this works, but from #2469 I thought it would behave like Docker, and that it would skip the stages that are not needed for the build.

Steps to reproduce the issue:

1. Create a multi-stage Dockerfile
2. Build the Dockerfile with --target parameter

Describe the results you received:

❯ podman build --target local .
[1/3] STEP 1/1: FROM golang AS base
--> 26b88b86d19
[3/3] STEP 1/3: FROM 26b88b86d196c85f18b7a014d9d6a0e449e5d60dbd5a46af56289e711bbc8d37 AS local
[3/3] STEP 2/3: COPY . /go/src/go-test/
--> eb34f827f3d
[3/3] STEP 3/3: RUN go build /go/src/go-test/main.go
[3/3] COMMIT
--> e10acebc5fa
[2/3] STEP 1/2: FROM 26b88b86d196c85f18b7a014d9d6a0e449e5d60dbd5a46af56289e711bbc8d37 AS foo
[2/3] STEP 2/2: RUN echo "foo"
foo
--> fe9ccbf8966
e10acebc5fa6259e505f6cf30ca8b5494bad766e6d12fa18b3caf1b0adaa746a

Describe the results you expected:

❯ podman build --target local .
[1/3] STEP 1/1: FROM golang AS base
--> 26b88b86d19
[3/3] STEP 1/3: FROM 26b88b86d196c85f18b7a014d9d6a0e449e5d60dbd5a46af56289e711bbc8d37 AS local
[3/3] STEP 2/3: COPY . /go/src/go-test/
--> eb34f827f3d
[3/3] STEP 3/3: RUN go build /go/src/go-test/main.go
[3/3] COMMIT
--> e10acebc5fa

Output of podman version if reporting a podman build issue:

❯ podman version
Client:       Podman Engine
Version:      4.2.0
API Version:  4.2.0
Go Version:   go1.18.5
Built:        Wed Aug 10 13:46:05 2022
OS/Arch:      darwin/arm64

Server:       Podman Engine
Version:      4.1.1
API Version:  4.1.1
Go Version:   go1.18.4
Built:        Fri Jul 22 12:06:49 2022
OS/Arch:      linux/arm64

Output of uname -a:

Darwin WC14D5QQWT 21.6.0 Darwin Kernel Version 21.6.0: Sat Jun 18 17:07:22 PDT 2022; root:xnu-8020.140.41~1/RELEASE_ARM64_T6000 arm64

[lucacome]

Well I just realized after posting that it says

....
Server:       Podman Engine
Version:      4.1.1
API Version:  4.1.1
Go Version:   go1.18.4
Built:        Fri Jul 22 12:06:49 2022
OS/Arch:      linux/arm64

so maybe this is the problem? That it's 4.1.1? But I'm not sure why the Server and Client versions are not matching....

[rhatdan]

The Server is based on Fedora CoreOS which only updates every couple of weeks on released version. So it might not be out for a week or so.
Reopen if/when the podman 4.2 version on the server breaks.

[lucacome]

I just wanted to let you know that I confirmed that with version 4.2.0 of the server everything works as expected. Sorry for the noise!