add build system for the images using mage

.gitignore

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+mage_output_file.go

mage.go

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+// +build mage
+
+// for use with https://github.com/magefile/mage
+
+package main
+
+import (
+	"context"
+	"log"
+	"os"
+	"os/exec"
+	"path/filepath"
+
+	"github.com/jtolds/qod"
+	"github.com/magefile/mage/mg"
+)
+
+var wd string
+
+func init() {
+	lwd, err := os.Getwd()
+	qod.ANE(err)
+
+	wd = lwd
+}
+
+func shouldWork(ctx context.Context, dir string, cmdName string, args ...string) {
+	loc, err := exec.LookPath(cmdName)
+	qod.ANE(err)
+
+	cmd := exec.CommandContext(ctx, loc, args...)
+	cmd.Dir = dir
+
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+
+	log.Printf("starting process, pwd: %s, cmd: %s, args: %v", dir, loc, args)
+	err = cmd.Run()
+	qod.ANE(err)
+}
+
+// All builds every image in order.
+func All() {
+	// Base image
+	mg.Deps(Base)
+
+	// Programming language specific images
+	mg.Deps(Go, GoMini, Nim)
+
+	qod.Printlnf("all images built :)")
+}
+
+// Base builds the base image xena/alpine.
+func Base() {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	dir := filepath.Join(wd, "./base/alpine")
+
+	// pull base alpine edge image for rebuilds
+	shouldWork(ctx, dir, "docker", "pull", "alpine:edge")
+
+	// build and push
+	shouldWork(ctx, dir, "box", "box.rb")
+	shouldWork(ctx, dir, "docker", "push", "xena/alpine:latest")
+}
+
+// Go builds the 'thick' go image xena/go.
+// https://golang.org
+func Go() {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	dir := filepath.Join(wd, "./lang/go")
+
+	// build and push
+	shouldWork(ctx, dir, "box", "box.rb")
+	shouldWork(ctx, dir, "docker", "push", "xena/go:1.9")
+	// XXX when go 1.9.1, etc comes out
+	//shouldWork(ctx, dir, "docker", "push", "xena/go:1.9.1")
+}
+
+// GoMini builds the 'mini' version of the compiler using golang.org/x/build/version.
+// https://golang.org
+func GoMini() {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	dir := filepath.Join(wd, "./lang/go-mini")
+
+	// build and push
+	shouldWork(ctx, dir, "box", "box.rb")
+	shouldWork(ctx, dir, "docker", "push", "xena/go-mini:1.9")
+	// XXX when go 1.9.1, etc comes out
+	//shouldWork(ctx, dir, "docker", "push", "xena/go:1.9.1")
+}
+
+// Nim builds the image for xena/nim
+// https://nim-lang.org
+func Nim() {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	dir := filepath.Join(wd, "./lang/nim")
+
+	// build and push
+	shouldWork(ctx, dir, "box", "box.rb")
+	shouldWork(ctx, dir, "docker", "push", "xena/nim:0.17.2")
+}