add configuration to use nginx-golang-postgres sample with Docker Dev Environments feature

Signed-off-by: Guillaume Lours <guillaume.lours@docker.com>

nginx-golang-postgres/backend/Dockerfile

@@ -1,9 +1,29 @@
-FROM golang:1.13-alpine AS build
+# syntax=docker/dockerfile:1.4
+
+FROM --platform=$BUILDPLATFORM golang:1.18 AS build
 WORKDIR /go/src/github.com/org/repo
+COPY go.* .
 COPY . .
 
+ENV CGO_ENABLED=0
 RUN go build -o server .
 
+FROM build as dev-envs
+
+RUN <<EOF
+apt-get update
+apt-get install -y --no-install-recommends git
+EOF
+
+RUN <<EOF
+useradd -s /bin/bash -m vscode
+groupadd docker
+usermod -aG docker vscode
+EOF
+# install Docker tools (cli, buildx, compose)
+COPY --from=gloursdocker/docker / /
+CMD ["go", "run", "main.go"]
+
 FROM alpine:3.12
 EXPOSE 8000
 COPY --from=build /go/src/github.com/org/repo/server /server

nginx-golang-postgres/backend/go.mod

@@ -1,10 +1,11 @@
 module github.com/org/repo
 
-go 1.13
+go 1.18
 
 require (
-	github.com/gorilla/context v1.1.1
-	github.com/gorilla/handlers v1.3.0
-	github.com/gorilla/mux v1.6.2
-	github.com/lib/pq v1.10.3
+	github.com/gorilla/handlers v1.5.1
+	github.com/gorilla/mux v1.8.0
+	github.com/lib/pq v1.10.6
 )
+
+require github.com/felixge/httpsnoop v1.0.1 // indirect

nginx-golang-postgres/backend/go.sum

@@ -0,0 +1,8 @@
+github.com/felixge/httpsnoop v1.0.1 h1:lvB5Jl89CsZtGIWuTcDM1E/vkVs49/Ml7JJe07l8SPQ=
+github.com/felixge/httpsnoop v1.0.1/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=
+github.com/gorilla/handlers v1.5.1 h1:9lRY6j8DEeeBT10CvO9hGW0gmky0BprnvDI5vfhUHH4=
+github.com/gorilla/handlers v1.5.1/go.mod h1:t8XrUpc4KVXb7HGyJ4/cEnwQiaxrX/hz1Zv/4g96P1Q=
+github.com/gorilla/mux v1.8.0 h1:i40aqfkR1h2SlN9hojwV5ZA91wcXFOvkdNIeFDP5koI=
+github.com/gorilla/mux v1.8.0/go.mod h1:DVbg23sWSpFRCP0SfiEN6jmj59UnW/n46BH5rLB71So=
+github.com/lib/pq v1.10.6 h1:jbk+ZieJ0D7EVGJYpL9QTz7/YW6UHbmdnZWYyK5cdBs=
+github.com/lib/pq v1.10.6/go.mod h1:AlVN5x4E4T544tWzH6hKfbfQvm3HdbOxrmggDNAPY9o=