1.9 KiB
examples/starter/Dockerfile.example
Naming
EXAMPLE — a component image. Copy, rename, replace. Named like the manifest it feeds and the resource it becomes:
Dockerfile.api -> image <cluster>-api -> image: in k8s/base/api.yaml
That image string is the ONLY thing connecting the three. Nothing checks it; a typo shows up as a pod stuck in ImagePullBackOff pulling from the public index, which reads like a network problem and is not one.
COPY paths are relative to the build context
The overlay's Tiltfile runs from the overlay's own folder (rig's ctrl/Tiltfile includes it), so both paths in docker_build are relative to the overlay:
context='.' the overlay folder (or a subfolder, e.g. 'repodir/api')
dockerfile='Dockerfile.api' relative to the overlay's Tiltfile too
Every COPY is resolved against the context, NOT against the Dockerfile's directory. With context='.' and the Dockerfile in a subfolder, a file sitting right beside it is still reached through that subfolder:
COPY docker/nginx.conf /etc/nginx/conf.d/default.conf # correct, Dockerfile in docker/
COPY nginx.conf /etc/nginx/conf.d/default.conf # fails — no such file in the context
Nothing warns you. The build just cannot find a file that is visibly there.
Before overlays, rig's own ctrl/Tiltfile built with context='..' (the repository root) and the Dockerfile in ctrl/, which is the same trap one level up.
Dependency layer
Dependencies first, in their own layer: they change far less often than the code, so a source edit does not reinstall them on every rebuild.
live_update
The sync in the Tiltfile's docker_build must land where this image expects it:
live_update=[sync('api', '/app/api')]
matches COPY api/ ./api/ with WORKDIR /app. If the two disagree, Tilt syncs into a path nothing reads and the container keeps serving the built copy — edits appear to do nothing, with no error anywhere.