Implements bootstrap, fixes #3

bootstrap.config.go

@@ -0,0 +1,7 @@
+// Copyright 2018 Mikhail Klementev. All rights reserved.
+// Use of this source code is governed by a AGPLv3 license
+// (or later) that can be found in the LICENSE file.
+
+package main
+
+const imagesURL = "https://github.com/jollheef/out-of-tree/releases/download/v0.2/images.tar.gz"

bootstrap.go

@@ -0,0 +1,76 @@
+// Copyright 2018 Mikhail Klementev. All rights reserved.
+// Use of this source code is governed by a AGPLv3 license
+// (or later) that can be found in the LICENSE file.
+
+package main
+
+import (
+	"io"
+	"io/ioutil"
+	"log"
+	"net/http"
+	"os"
+	"os/exec"
+	"os/user"
+)
+
+// inspired by Edd Turtle code
+func downloadFile(filepath string, url string) (err error) {
+	out, err := os.Create(filepath)
+	if err != nil {
+		return
+	}
+	defer out.Close()
+
+	resp, err := http.Get(url)
+	if err != nil {
+		return
+	}
+	defer resp.Body.Close()
+
+	_, err = io.Copy(out, resp.Body)
+	return
+}
+
+func unpackTar(archive, destination string) (err error) {
+	cmd := exec.Command("tar", "xf", archive)
+	cmd.Dir = destination + "/"
+
+	rawOutput, err := cmd.CombinedOutput()
+	if err != nil {
+		// I don't like when some errors printed inside
+		// So if you know way to do it better - FIXME please
+		log.Println("Unpack images error:", string(rawOutput), err)
+		return
+	}
+
+	return
+}
+
+func bootstrapHandler() (err error) {
+	usr, err := user.Current()
+	if err != nil {
+		return
+	}
+
+	imagesPath := usr.HomeDir + "/.out-of-tree/images/"
+	os.MkdirAll(imagesPath, os.ModePerm)
+
+	tmp, err := ioutil.TempDir("/tmp/", "out-of-tree_")
+	if err != nil {
+		log.Println("Temporary directory creation error:", err)
+		return
+	}
+	defer os.RemoveAll(tmp)
+
+	imagesArchive := tmp + "/images.tar.gz"
+
+	err = downloadFile(imagesArchive, imagesURL)
+	if err != nil {
+		log.Println("Download file error:", err)
+		return
+	}
+
+	err = unpackTar(imagesArchive, imagesPath)
+	return
+}

main.go

@@ -78,6 +78,9 @@ func main() {
 	debugFlagGDB := debugCommand.Flag("gdb", "Set gdb listen address")
 	debugGDB := debugFlagGDB.Default("tcp::1234").String()
 
+	bootstrapCommand := app.Command("bootstrap",
+		"Create directories && download images")
+
 	// Check for required commands
 	for _, cmd := range []string{"timeout", "docker", "qemu"} {
 		_, err := exec.Command("which", cmd).CombinedOutput()
@@ -123,6 +126,8 @@ func main() {
 	case debugCommand.FullCommand():
 		err = debugHandler(kcfg, *path, *debugKernel, *debugGDB,
 			*dockerTimeout)
+	case bootstrapCommand.FullCommand():
+		err = bootstrapHandler()
 	}
 
 	if err != nil {