refactor: simpler dockerfile builder

Signed-off-by: peefy <[email protected]>

.github/workflows/release.yaml

@@ -82,6 +82,6 @@ jobs:
           builder: ${{ steps.buildx.outputs.name }}
           context: .
           file: ./Dockerfile
-          platforms: linux/amd64, linux/arm64
+          platforms: linux/amd64
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}

Dockerfile

@@ -1,27 +1,43 @@
+# We use the Go 1.22 version unless asked to use something else.
+# The GitHub Actions CI job sets this argument for a consistent Go version.
 ARG GO_VERSION=1.22
+ARG BASE_IMAGE=kcllang/kcl
 
+# Setup the base environment. The BUILDPLATFORM is set automatically by Docker.
+# The --platform=${BUILDPLATFORM} flag tells Docker to build the function using
+# the OS and architecture of the host running the build, not the OS and
+# architecture that we're building the function for.
 FROM --platform=$BUILDPLATFORM golang:${GO_VERSION} as build
 
 COPY / /src
 WORKDIR /src
 
+ENV CGO_ENABLED=0
+
+# We run go mod download in a separate step so that we can cache its results.
+# This lets us avoid re-downloading modules if we don't need to. The type=target
+# mount tells Docker to mount the current directory read-only in the WORKDIR.
+# The type=cache mount tells Docker to cache the Go modules cache across builds.
+RUN --mount=target=. --mount=type=cache,target=/go/pkg/mod go mod download
+
 # The TARGETOS and TARGETARCH args are set by docker. We set GOOS and GOARCH to
 # these values to ask Go to compile a binary for these architectures. If
 # TARGETOS and TARGETOS are different from BUILDPLATFORM, Go will cross compile
 # for us (e.g. compile a linux/amd64 binary on a linux/arm64 build machine).
 ARG TARGETOS
 ARG TARGETARCH
 
-# build
-ENV CGO_ENABLED=0
-RUN go build -a -o kcl-controller cmd/main.go
-
-FROM kcllang/kcl
+# Build the function binary. The type=target mount tells Docker to mount the
+# current directory read-only in the WORKDIR. The type=cache mount tells Docker
+# to cache the Go modules cache across builds.
+RUN --mount=target=. \
+    --mount=type=cache,target=/go/pkg/mod \
+    --mount=type=cache,target=/root/.cache/go-build \
+    GOOS=${TARGETOS} GOARCH=${TARGETARCH} go build -a -o kcl-controller cmd/main.go
 
+FROM ${BASE_IMAGE} as image
 RUN apt-get update && apt-get install -y ca-certificates tini
-
 COPY --from=build /src/kcl-controller /usr/local/bin/
-
 # RUN addgroup -S controller && adduser -S controller -G controller
 RUN groupadd controller && useradd -g controller controller
 

README.md

@@ -112,3 +112,7 @@ nginx-deployment-1   1/1     1            0           4s
 ```
 
 kcl-controller creates a `nginx-deployment-1` according to the KCL program in the repository.
+
+git tag v0.3.1
+git push origin v0.3.1
+gh release create v0.3.1 --draft --generate-notes --title "v0.3.1 Release"