Merge pull request #16 from shipwright-io/sascha-add-docker-build-wit…

…h-broken-final-stage

Add Docker build with broken final stage

docker-build-with-broken-final-stage/Dockerfile

@@ -0,0 +1,19 @@
+# From https://github.com/homeport/gonut/tree/master/assets/sample-apps/golang
+
+FROM ghcr.io/shipwright-io/shipwright-samples/golang:1.18 AS build
+
+COPY main.go .
+ENV CGO_ENABLED=0
+RUN go build \
+    -ldflags "-s -w -extldflags '-static'" \
+    -o /tmp/helloworld \
+    main.go
+
+FROM scratch AS working-final
+COPY --from=build /tmp/helloworld ./helloworld
+ENTRYPOINT [ "./helloworld" ]
+EXPOSE 8080
+
+# the following stage is INTENTIONALLY broken, one can only have a successful run when specifying working-final as target stage
+FROM scratch
+RUN non-existing-command

docker-build-with-broken-final-stage/main.go

@@ -0,0 +1,47 @@
+// Copyright The Shipwright Contributors
+//
+// SPDX-License-Identifier: Apache-2.0
+
+package main
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"net/http"
+	"os"
+	"os/signal"
+	"runtime"
+	"strconv"
+	"syscall"
+)
+
+func main() {
+	ctx := context.Background()
+	signals := make(chan os.Signal, 1)
+	signal.Notify(signals, os.Interrupt, syscall.SIGTERM)
+
+	port := 8080
+	if strValue, ok := os.LookupEnv("PORT"); ok {
+		if intValue, err := strconv.Atoi(strValue); err == nil {
+			port = intValue
+		}
+	}
+
+	srv := &http.Server{Addr: fmt.Sprintf(":%d", port)}
+	go func() {
+		http.HandleFunc("/", func(w http.ResponseWriter, _ *http.Request) {
+			fmt.Fprintf(w, "Hello, World! I am using %s by the way.", runtime.Version())
+		})
+
+		if err := srv.ListenAndServe(); err != http.ErrServerClosed {
+			log.Fatalf("failed to start server: %v", err)
+		}
+	}()
+
+	<-signals
+	log.Printf("shutting down server")
+	if err := srv.Shutdown(ctx); err != nil {
+		log.Fatalf("failed to shutdown server: %v", err)
+	}
+}