scratch-distroless-docker

package main

import (
    "fmt"
    "log"
    "net/http"
)

func Hello(w http.ResponseWriter, r *http.Request) {
    w.WriteHeader(http.StatusOK)
    w.Write([]byte("Hello, welcome to the world, Go!"))
}

func main() {

    mux := http.NewServeMux()
    mux.Handle("/api/hello", http.HandlerFunc(Hello))

    server :=
        &http.Server{
            Addr:    ":8080",
            Handler: mux,
        }

    fmt.Printf("Server Run port: 8080\n")
    if err := server.ListenAndServe(); err != nil {
        log.Printf("Eror while serving metrics: %s", err)
    }
}

/// curl localhost:8080/api/hello

# compilar
$ CGO_ENABLED=0 GOOS=linux go build -a -installsuffix cgo

#################################################
# DockerFile scratch
#################################################
FROM scratch
ADD main /
CMD ["/main"]

-------------------------------------------------------------------------

#################################################
# Dockerfile distroless
#################################################
FROM golang:1.12.0 as builder
WORKDIR /go/src/main
ENV GO111MODULE=on
COPY . .
RUN go install -v ./...

############################
# STEP 2 build a small image
############################
FROM gcr.io/distroless/base
COPY --from=builder /go/bin/main /
CMD ["/main"]

-------------------------------------------------------------------------

#################################################
# Strach + Muiltistage
#################################################
FROM golang:1.12.0 as builder
WORKDIR /go/src/main
ENV GO111MODULE=on
COPY . .
RUN CGO_ENABLED=0 GOOS=linux go build -a -installsuffix cgo -o /app .

############################
# STEP 2 build a small image
############################
FROM scratch
COPY --from=0 /app /app
CMD ["/app"]

-------------------------------------------------------------------------

#################################################
# Alpine + Strach + Muiltistage
#################################################
FROM golang:alpine AS builder
# Install git.
# Git is required for fetching the dependencies.
RUN apk update && apk add --no-cache git
WORKDIR /go/src/main
ENV GO111MODULE=on
COPY . .
RUN CGO_ENABLED=0 GOOS=linux go build -a -installsuffix cgo -o /app .

############################
# STEP 2 build a small image
############################
FROM scratch
# Copy our static executable.
COPY --from=builder /app /app
# Run the hello binary.
ENTRYPOINT ["/app"]

Source Code Here:
https://github.com/jeffotoni/goexample/tree/master/api-simple

$ docker build -t example-golang-scratch -f Dockerfile .
$ docker run --rm -it example-golang-scratch
$ curl localhost:8080/api/hello

The disabling DWARF generation will greatly reduce the size of the binary because it will delete debug information without losing any functionality

GCO_ENABLED=0 GOOS=linux go build -ldflags "-s -w" -a -installsuffix cgo -o /app

Sample:

FROM golang:alpine AS builder
RUN apk update && apk add --no-cache git build-base
WORKDIR /go/src/main
ENV GO111MODULE=on
COPY . .
RUN GCO_ENABLED=0 GOOS=linux go build -ldflags "-s -w" -a -installsuffix cgo -o /app .

FROM scratch
COPY --from=builder /app /app
ENTRYPOINT ["/app"]

@BrunoBMelo Perfect 😍