I have done the following
Steps to reproduce
Try and build the following containerfile:
ARG TAG="${TAG:-latest}"
FROM docker.io/library/alpine:${TAG}
RUN echo ok
Problem description
When building with default args, I get the following error:
➜ mvp-error container build
[+] Building 0.0s (0/0)
Error: unknown (2): failed to solve: invalid ref: docker.io/library/alpine:${TAG}
Expected behaviour should match podman or docker where they use :latest tag for sample image:
➜ mvp-error docker build .
[+] Building 0.5s (6/6) FINISHED docker:desktop-linux
=> [internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 111B 0.0s
=> [internal] load metadata for docker.io/library/alpine:latest 0.4s
=> [internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [1/2] FROM docker.io/library/alpine:latest@sha256:28bd5fe8b56d1bd048e5babf5b10710ebe0bae67db86916198a6eec434943f8b 0.0s
=> => resolve docker.io/library/alpine:latest@sha256:28bd5fe8b56d1bd048e5babf5b10710ebe0bae67db86916198a6eec434943f8b 0.0s
=> CACHED [2/2] RUN echo ok 0.0s
=> exporting to image 0.0s
=> => exporting layers 0.0s
=> => exporting manifest sha256:3cfd1f1c63292a946d97d643b56cb230284724a6c3f884a80646fe68796b455a 0.0s
=> => exporting config sha256:bc70131ba5c16c30df94fbaf4d61ac5f8160f70edfbfa36e79f99ce2747fd366 0.0s
=> => exporting attestation manifest sha256:317c203aa45b3e782b2d7435ce09cde0219c98c2f6a0e1fd0dec79a3b8bb5a3f 0.0s
=> => exporting manifest list sha256:9282520c0e9a0ac0544cdd4f015aaec553a28854646fd024f25be758979d6882 0.0s
=> => naming to moby-dangling@sha256:9282520c0e9a0ac0544cdd4f015aaec553a28854646fd024f25be758979d6882 0.0s
=> => unpacking to moby-dangling@sha256:9282520c0e9a0ac0544cdd4f015aaec553a28854646fd024f25be758979d6882 0.0s
View build details: docker-desktop://dashboard/build/desktop-linux/desktop-linux/d2iqo4jqxllanvszslk56p8id
What's next:
View a summary of image vulnerabilities and recommendations → docker scout quickview
➜ mvp-error podman build .
STEP 1/2: FROM docker.io/library/alpine:latest
STEP 2/2: RUN echo ok
ok
COMMIT
--> 3c0ea4ac2df7
3c0ea4ac2df7b582868a11ea54a8082ef302f2a32997f5e8a3a50554af5b0141
Environment
- OS: macOS 26.5.1 (25F80)
- Xcode: Version 26.5 (17F42)
- Container: container CLI version 0.6.0 (build: release, commit: a23bcf0)
Code of Conduct
I have done the following
Steps to reproduce
Try and build the following containerfile:
Problem description
When building with default args, I get the following error:
Expected behaviour should match podman or docker where they use
:latesttag for sample image:Environment
Code of Conduct