Syft does not log warnings when no tty is present

[devfbe]

What happened: Important WARN logs like

[0000]  WARN file could not be unarchived: unable to create tempdir for archive processing: stat /tmp: no such file or directory

Are not visible / not logged, when no TTY is present. This happens especially in my GitLab pipelines where jobs do not have a tty.

What you expected to happen: I expect that all logs, especially with Level >= WARN are being logged when /dev/stdout and /dev/stderr are present. A missing (pseudo)tty should not cause missing logs.

Steps to reproduce the issue: Build a container with a broken environment where no temp dir exists and try to scan a test artifact (in my case containerimage.tar) in this container. 1 Try with a pseudo tty and one time without a tty. You'll see the warnings only, when a pseudo tty has been allocated. I verified, that even without the pseudo tty, /dev/stdout and /dev/stderr are there and work as intended.

Test container:

FROM scratch
COPY syft /
COPY containerimage.tar /
ENTRYPOINT ["/syft"]

Run without tty:

❯ podman run -i syft scan /containerimage.tar
No packages discovered

Run with pseudo tty:

❯ podman run -ti syft scan /containerimage.tar
 ✔ Indexed file system                                                                                                                                                                                                                                                                 /
 ✔ Cataloged contents                                                                                                                                                                                                   ccf875aa8af6073319964e9d36823bf7337a7ca8caf5c386c818452a7307c45f
   ├── ✔ Packages                        [0 packages]
   └── ✔ Executables                     [0 executables]
[0000]  WARN file could not be unarchived: unable to create tempdir for archive processing: stat /tmp: no such file or directory
[0001]  WARN unable to determine GOPATH or user home dir: %!w(string=exec: "getent": executable file not found in $PATH)
[0001]  WARN unable to determine GOPATH or user home dir: %!w(string=exec: "getent": executable file not found in $PATH)
No packages discovered

Anything else we need to know?: I assume that the logs are missing, because when no TTY is there some special terminal tricks like animations don't work.

Environment:

• Syft 1.9.0
• OCI-Container of all kind