go言語用dockerfile

Dockerfile

FROM golang:1.15-buster AS debug
WORKDIR /app
COPY . .
RUN curl -sSfL https://raw.githubusercontent.com/cosmtrek/air/master/install.sh | sh -s -- -b $(go env GOPATH)/bin
CMD air

FROM golang:1.15-buster AS build
WORKDIR /app
ENV CGO_ENABLED=0
COPY go.* ./
RUN go mod download
COPY . ./
RUN GOOS=linux go build -mod=readonly -v -o server

# k8s、cloud-run用ビルド --target deploy
FROM alpine:3 AS deploy
RUN apk --no-cache add tzdata && \
    cp /usr/share/zoneinfo/Asia/Tokyo /etc/localtime
RUN apk add --no-cache ca-certificates
COPY --from=build /app/server /server
CMD ["/server"]

マルチステージビルドで、
開発用のdebugにはAirを導入