dockerfile-best-practices.md

Docker file best practices

1. order instruction by least to most frequent changing content
2. Avoid COPY . (Copy only what is needed if possible)
3. Don’t use latest tag, add a specific version
4. Multi stage build -
   1. DRY
   2. small image size
   3. Build different image for test/run/lint from base buiilt image

FROM image_or_stage AS stage_name docker build —target=stage name For building only the specific stage with all of its dependent stage

// default var flavour
ARG flavour alpine

FROM <> as builder
…
…

FROM <>-$flavour AS release
COPY —from=builder ….

$docker build --target=release —build-args flavour=jessie