Is it possible to view the Dockerfile used to build a container?

[sliekens]

I'm having some issues configuring NODE_EXTRA_CA_CERTS which is needed for VSCode to be able to reach the internet from behind my corporate firewall which decrypts encrypted traffing and re-encrypts with our inhouse CA certificate.

I am setting "containerEnv": { "NODE_EXTRA_CA_CERTS": "path-to-bundle.crt" } inside a devcontainer feature but I guess it's not doing what I expected it to, extensions listed in devcontainer.json are not installed when the container starts.

Can I somehow view the Dockerfile which is generated from a devcontainer.json definition?

[samruddhikhandale]

Reading through the CLI code, it looks like we save the Dockerfile created by Features in a /tmp folder. However, I don't think that's available later.

See 👇

Looping in @joshspicer in case I am misinterpreting.

[joshspicer]

Yea, we do write the Dockerfile to a temporary path (and use that Dockerfile when running the build). Searching your disk for some string like dev_containers_target_stage as shown in @samruddhikhandale 's message above is probably the easiest way to dig through that file. Note it's temporary and might be deleted by your OS.

That said, there's a good amount of info captured in some older, closed GitHub issues - like in this issue. That might be a more helpful place to look?

If you'd like to audit the change in the CLI where NODE_EXTRA_CA_CERTS is handled, it was added in this release

[sliekens]

Thanks, I found the file in /tmp/devcontainercli-<user>/container-features/0.56.2-1710936344096/Dockerfile-with-features

Also thank you for the link to the NODE_EXTRA_CA_CERTS changes. I am setting ENV NODE_EXTRA_CA_CERTS="/usr/local/share/ca-certificates/bundle.crt" via containerEnv, but maybe that is no longer needed then, I will have to investigate further.

However, I found that my real issue seems to be the same as this: microsoft/vscode#207813

Anyhow, thanks for your time.