Cache does not seem to be used

Behaviour

Hi ! Thank you for your great peace of work here !

It looks like the cache feature is not used during docker build.

Or I may have misunderstood something ! 🤷‍♂️ (I’ve never used buildx yet, only Buildkit but without thinking about the caching part).

Thank you for your help !

Expected behaviour

I think Golang and Alpine images should almost always be retrieved by cache

Regarding the setup-buildx action, it would be great to use caching too so that we don’t loose around 13s on every action trigger

Actual behaviour

At this time it is not

Cache works well if I relaunch the action without making any changes

Configuration

name: ci
on: [pull_request,release]
jobs:
  docker-build-and-push:
    runs-on: ubuntu-latest
    steps:
      -
        name: Checkout repository
        uses: actions/checkout@v2
      -
        name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v1
      -
        name: Cache Docker layers
        uses: actions/cache@v2
        with:
          path: /tmp/.buildx-cache
          key: ${{ runner.os }}-buildx-${{ github.sha }}
          restore-keys: |
            ${{ runner.os }}-buildx-
      -
        name: Login to Azure Container Registry
        uses: docker/login-action@v1
        with:
          registry: ${{ secrets.CONTAINER_REGISTRY_NAME }}
          username: ${{ secrets.CONTAINER_REGISTRY_USERNAME }}
          password: ${{ secrets.CONTAINER_REGISTRY_PASSWORD }}
      -
        name: Build and push docker image
        id: docker_build
        uses: docker/build-push-action@v2
        with:
          context: .
          push: true
          tags: ${{ secrets.CONTAINER_REGISTRY_NAME }}/${{ github.event.repository.name }}:${{ github.head_ref }}
          cache-from: type=local,src=/tmp/.buildx-cache
          cache-to: type=local,dest=/tmp/.buildx-cache

here is the Dockerfile:

FROM golang:1.15-alpine AS builder
WORKDIR /project
COPY . .
RUN CGO_ENABLED=0 go build -ldflags="-s -w" -o backend-ads-api ./cmd/...

FROM alpine:3.12
COPY --from=builder /project/backend-ads-api .
ENTRYPOINT ["/backend-ads-api"]

and the .dockerignore if it helps:

.git
.gitignore
.dockerignore
.github

.idea

Dockerfile

*test.go
README.md
LICENSE

Logs

logs_42.zip

[crazy-max]

@rmasclef

So why using buildx/buildkit when a “basic” docker **build** allows base image caching ?

Can you open an issue on buildkit repo? WDYT @tonistiigi?

Well, in our case, we are on a Github Team plan so we have 3000 minutes available every month. And as we have about 30 projects, every gained build second is clearly welcome don’t you think ?

This is perfectly understandable. Perhaps there is some room for caching the moby/buildkit image. Can you open an issue on setup-buildx repo about that? Thanks.

[rmasclef]

thank you for your answers 👍

Upstream so yeah for buildx/builkit.

So why using buildx/buildkit when a “basic” docker **build** allows base image caching ?

I don’t see how we could optimize this action even better and I don’t think that 13s vs 5s really makes much difference 😅

Well, in our case, we are on a Github Team plan so we have 3000 minutes available every month. And as we have about 30 projects, every gained build second is clearly welcome don’t you think ?

I know that, most of the time, we can optimize build time by optimizing the Dockerfile, but I don’t think I can optimize more in the case of a Go project though I’m really welcome to get advises on what I’ve done so far ! 😄