Merge pull request #770 from mengqiy/cachegomod

✨ cache go module cache in docker

Author: k8s-ci-robot

pkg/scaffold/v2/dockerfile.go

@@ -40,14 +40,17 @@ var dockerfileTemplate = `# Build the manager binary
 FROM golang:1.12.5 as builder
 
 WORKDIR /workspace
-# Copy the go source
-COPY main.go main.go
-COPY api/ api/
-COPY controllers/ controllers/
 # Copy the Go Modules manifests
 COPY go.mod go.mod
 COPY go.sum go.sum
+# cache deps before building and copying source so that we don't need to re-download as much
+# and so that source changes don't invalidate our downloaded layer
+RUN go mod download
 
+# Copy the go source
+COPY main.go main.go
+COPY api/ api/
+COPY controllers/ controllers/
 
 # Build
 RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 GO111MODULE=on go build -a -o manager main.go

testdata/project-v2/Dockerfile

@@ -2,14 +2,17 @@
 FROM golang:1.12.5 as builder
 
 WORKDIR /workspace
-# Copy the go source
-COPY main.go main.go
-COPY api/ api/
-COPY controllers/ controllers/
 # Copy the Go Modules manifests
 COPY go.mod go.mod
 COPY go.sum go.sum
+# cache deps before building and copying source so that we don't need to re-download as much
+# and so that source changes don't invalidate our downloaded layer
+RUN go mod download
 
+# Copy the go source
+COPY main.go main.go
+COPY api/ api/
+COPY controllers/ controllers/
 
 # Build
 RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 GO111MODULE=on go build -a -o manager main.go