Implements stateless VMs

This commit is contained in:
Mikhail Klementev 2020-01-03 22:56:27 +00:00
parent e037770c38
commit 355fb314a1
No known key found for this signature in database
GPG key ID: BE44DA8C062D87DC
2 changed files with 70 additions and 16 deletions

View file

@ -13,6 +13,7 @@ import (
"io"
"io/ioutil"
"log"
"math/rand"
"net"
"os"
"os/exec"
@ -165,7 +166,8 @@ func isRunning(l *libvirt.Libvirt, name string) bool {
return err == nil
}
func generateAppVM(l *libvirt.Libvirt, name, appvmPath, sharedDir string,
func generateAppVM(l *libvirt.Libvirt,
nixName, vmName, appvmPath, sharedDir string,
verbose, online bool) (err error) {
err = os.Chdir(appvmPath)
@ -173,12 +175,12 @@ func generateAppVM(l *libvirt.Libvirt, name, appvmPath, sharedDir string,
return
}
realpath, reginfo, qcow2, err := generateVM(name, verbose)
realpath, reginfo, qcow2, err := generateVM(nixName, verbose)
if err != nil {
return
}
xml := generateXML(name, online, realpath, reginfo, qcow2, sharedDir)
xml := generateXML(vmName, online, realpath, reginfo, qcow2, sharedDir)
_, err = l.DomainCreateXML(xml, libvirt.DomainStartValidate)
return
}
@ -207,14 +209,31 @@ func isAppvmConfigurationExists(appvmPath, name string) bool {
return fileExists(appvmPath + "/nix/" + name + ".nix")
}
func start(l *libvirt.Libvirt, name string, verbose, online bool,
func start(l *libvirt.Libvirt, name string, verbose, online, stateless bool,
args, open string) {
appvmPath := configDir
vmHomePath := os.Getenv("HOME") + "/appvm/" + name + "/"
statelessName := fmt.Sprintf("tmp_%d_%s", rand.Int(), name)
sharedDir := os.Getenv("HOME") + "/appvm/"
if stateless {
sharedDir += statelessName
} else {
sharedDir += name
}
os.MkdirAll(sharedDir, 0700)
vmName := "appvm_"
if stateless {
vmName += statelessName
} else {
vmName += name
}
if open != "" {
filename := vmHomePath + filepath.Base(open)
filename := sharedDir + "/" + filepath.Base(open)
err := copyFile(open, filename)
if err != nil {
log.Println("Can't copy file")
@ -225,7 +244,7 @@ func start(l *libvirt.Libvirt, name string, verbose, online bool,
}
if args != "" {
err := ioutil.WriteFile(vmHomePath+".args", []byte(args), 0700)
err := ioutil.WriteFile(sharedDir+"/"+".args", []byte(args), 0700)
if err != nil {
log.Println("Can't write args")
return
@ -248,21 +267,19 @@ func start(l *libvirt.Libvirt, name string, verbose, online bool,
log.Fatal(err)
}
if !isRunning(l, name) {
if !isRunning(l, vmName) {
if !verbose {
go stupidProgressBar()
}
sharedDir := fmt.Sprintf(os.Getenv("HOME") + "/appvm/" + name)
os.MkdirAll(sharedDir, 0700)
err = generateAppVM(l, name, appvmPath, sharedDir, verbose, online)
err = generateAppVM(l, name, vmName, appvmPath, sharedDir,
verbose, online)
if err != nil {
log.Fatal(err)
}
}
cmd := exec.Command("virt-viewer", "-c", "qemu:///system", "appvm_"+name)
cmd := exec.Command("virt-viewer", "-c", "qemu:///system", vmName)
cmd.Start()
}
@ -366,9 +383,40 @@ func sync() {
log.Println("Done")
}
func cleanupStatelessVMs(l *libvirt.Libvirt) {
domains, err := l.Domains()
if err != nil {
log.Fatal(err)
}
dirs, err := ioutil.ReadDir(appvmHomesDir)
if err != nil {
log.Fatal(err)
}
for _, f := range dirs {
if !strings.HasPrefix(f.Name(), "tmp_") {
continue
}
alive := false
for _, d := range domains {
if d.Name == "appvm_"+f.Name() {
alive = true
}
}
if !alive {
os.RemoveAll(appvmHomesDir + f.Name())
}
}
}
var configDir = os.Getenv("HOME") + "/.config/appvm/"
var appvmHomesDir = os.Getenv("HOME") + "/appvm/"
func main() {
rand.Seed(time.Now().UnixNano())
os.Mkdir(os.Getenv("HOME")+"/appvm", 0700)
os.MkdirAll(configDir+"/nix", 0700)
@ -394,6 +442,8 @@ func main() {
}
defer l.Disconnect()
cleanupStatelessVMs(l)
kingpin.Command("list", "List applications")
autoballonCommand := kingpin.Command("autoballoon", "Automatically adjust/reduce app vm memory")
minMemory := autoballonCommand.Flag("min-memory", "Set minimal memory (megabytes)").Default("1024").Uint64()
@ -405,6 +455,7 @@ func main() {
startArgs := startCommand.Flag("args", "Command line arguments").String()
startOpen := startCommand.Flag("open", "Pass file to application").String()
startOffline := startCommand.Flag("offline", "Disconnect").Bool()
startStateless := startCommand.Flag("stateless", "Do not use default state directory").Bool()
stopName := kingpin.Command("stop", "Stop application").Arg("name", "Application name").Required().String()
dropName := kingpin.Command("drop", "Remove application data").Arg("name", "Application name").Required().String()
@ -427,7 +478,8 @@ func main() {
case "generate":
generate(l, *generateName, *generateBin, *generateVMName)
case "start":
start(l, *startName, !*startQuiet, !*startOffline,
start(l, *startName,
!*startQuiet, !*startOffline, *startStateless,
*startArgs, *startOpen)
case "stop":
stop(l, *stopName)

6
xml.go
View file

@ -5,7 +5,9 @@ import "fmt"
// You may think that you want to rewrite to proper golang structures.
// Believe me, you shouldn't.
func generateXML(name string, online bool, vmNixPath, reginfo, img, sharedDir string) string {
func generateXML(vmName string, online bool,
vmNixPath, reginfo, img, sharedDir string) string {
qemuParams := `
<qemu:commandline>
<qemu:arg value='-device'/>
@ -24,7 +26,7 @@ func generateXML(name string, online bool, vmNixPath, reginfo, img, sharedDir st
`
}
return fmt.Sprintf(xmlTmpl, "appvm_"+name, vmNixPath, vmNixPath, vmNixPath,
return fmt.Sprintf(xmlTmpl, vmName, vmNixPath, vmNixPath, vmNixPath,
reginfo, img, sharedDir, sharedDir, sharedDir, qemuParams)
}