Add Go daemon-driven VM control plane

Replace the shell-only user workflow with `banger` and `bangerd`: Cobra commands, XDG/SQLite-backed state, managed VM and image lifecycle, and a Bubble Tea TUI for browsing and operating VMs.\n\nKeep Firecracker orchestration behind the daemon so VM specs become persistent objects, and add repo entrypoints for building, installing, and documenting the new flow while still delegating rootfs customization to the existing shell tooling.\n\nHarden the control plane around real usage by reclaiming Firecracker API sockets for the user, restarting stale daemons after rebuilds, and returning the correct `vm.create` payload so the CLI and TUI creation flow work reliably.\n\nValidation: `go test ./...`, `make build`, and a host-side smoke test with `./banger vm create --name codex-smoke`.
This commit is contained in:
Thales Maciel 2026-03-16 12:52:54 -03:00
parent 3cf33d1e0a
commit ea72ea26fe
No known key found for this signature in database
GPG key ID: 33112E6833C34679
22 changed files with 5480 additions and 0 deletions

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internal/daemon/daemon.go Normal file
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package daemon
import (
"bufio"
"context"
"encoding/json"
"errors"
"fmt"
"net"
"os"
"path/filepath"
"strings"
"sync"
"time"
"banger/internal/api"
"banger/internal/config"
"banger/internal/model"
"banger/internal/paths"
"banger/internal/rpc"
"banger/internal/store"
"banger/internal/system"
)
type Daemon struct {
layout paths.Layout
config model.DaemonConfig
store *store.Store
runner system.Runner
mu sync.Mutex
closing chan struct{}
once sync.Once
pid int
listener net.Listener
}
func Open(ctx context.Context) (*Daemon, error) {
layout, err := paths.Resolve()
if err != nil {
return nil, err
}
if err := paths.Ensure(layout); err != nil {
return nil, err
}
cfg, err := config.Load(layout)
if err != nil {
return nil, err
}
db, err := store.Open(layout.DBPath)
if err != nil {
return nil, err
}
d := &Daemon{
layout: layout,
config: cfg,
store: db,
runner: system.NewRunner(),
closing: make(chan struct{}),
pid: os.Getpid(),
}
if err := d.ensureDefaultImage(ctx); err != nil {
return nil, err
}
if err := d.reconcile(ctx); err != nil {
return nil, err
}
return d, nil
}
func (d *Daemon) Close() error {
var err error
d.once.Do(func() {
close(d.closing)
if d.listener != nil {
_ = d.listener.Close()
}
err = d.store.Close()
})
return err
}
func (d *Daemon) Serve(ctx context.Context) error {
_ = os.Remove(d.layout.SocketPath)
listener, err := net.Listen("unix", d.layout.SocketPath)
if err != nil {
return err
}
d.listener = listener
defer listener.Close()
defer os.Remove(d.layout.SocketPath)
if err := os.Chmod(d.layout.SocketPath, 0o600); err != nil {
return err
}
go d.backgroundLoop()
for {
conn, err := listener.Accept()
if err != nil {
select {
case <-ctx.Done():
return nil
case <-d.closing:
return nil
default:
}
if ne, ok := err.(net.Error); ok && ne.Temporary() {
time.Sleep(100 * time.Millisecond)
continue
}
return err
}
go d.handleConn(conn)
}
}
func (d *Daemon) handleConn(conn net.Conn) {
defer conn.Close()
var req rpc.Request
if err := json.NewDecoder(bufio.NewReader(conn)).Decode(&req); err != nil {
_ = json.NewEncoder(conn).Encode(rpc.NewError("bad_request", err.Error()))
return
}
resp := d.dispatch(req)
_ = json.NewEncoder(conn).Encode(resp)
}
func (d *Daemon) dispatch(req rpc.Request) rpc.Response {
if req.Version != rpc.Version {
return rpc.NewError("bad_version", fmt.Sprintf("unsupported version %d", req.Version))
}
ctx := context.Background()
switch req.Method {
case "ping":
result, _ := rpc.NewResult(api.PingResult{Status: "ok", PID: d.pid})
return result
case "shutdown":
go d.Close()
result, _ := rpc.NewResult(api.ShutdownResult{Status: "stopping"})
return result
case "vm.create":
params, err := rpc.DecodeParams[api.VMCreateParams](req)
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
vm, err := d.CreateVM(ctx, params)
return marshalResultOrError(api.VMShowResult{VM: vm}, err)
case "vm.list":
vms, err := d.store.ListVMs(ctx)
return marshalResultOrError(api.VMListResult{VMs: vms}, err)
case "vm.show":
params, err := rpc.DecodeParams[api.VMRefParams](req)
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
vm, err := d.FindVM(ctx, params.IDOrName)
return marshalResultOrError(api.VMShowResult{VM: vm}, err)
case "vm.start":
params, err := rpc.DecodeParams[api.VMRefParams](req)
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
vm, err := d.StartVM(ctx, params.IDOrName)
return marshalResultOrError(api.VMShowResult{VM: vm}, err)
case "vm.stop":
params, err := rpc.DecodeParams[api.VMRefParams](req)
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
vm, err := d.StopVM(ctx, params.IDOrName)
return marshalResultOrError(api.VMShowResult{VM: vm}, err)
case "vm.restart":
params, err := rpc.DecodeParams[api.VMRefParams](req)
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
vm, err := d.RestartVM(ctx, params.IDOrName)
return marshalResultOrError(api.VMShowResult{VM: vm}, err)
case "vm.delete":
params, err := rpc.DecodeParams[api.VMRefParams](req)
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
vm, err := d.DeleteVM(ctx, params.IDOrName)
return marshalResultOrError(api.VMShowResult{VM: vm}, err)
case "vm.set":
params, err := rpc.DecodeParams[api.VMSetParams](req)
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
vm, err := d.SetVM(ctx, params)
return marshalResultOrError(api.VMShowResult{VM: vm}, err)
case "vm.stats":
params, err := rpc.DecodeParams[api.VMRefParams](req)
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
vm, stats, err := d.GetVMStats(ctx, params.IDOrName)
return marshalResultOrError(api.VMStatsResult{VM: vm, Stats: stats}, err)
case "vm.logs":
params, err := rpc.DecodeParams[api.VMRefParams](req)
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
vm, err := d.FindVM(ctx, params.IDOrName)
if err != nil {
return rpc.NewError("not_found", err.Error())
}
return marshalResultOrError(api.VMLogsResult{LogPath: vm.Runtime.LogPath}, nil)
case "vm.ssh":
params, err := rpc.DecodeParams[api.VMRefParams](req)
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
vm, err := d.TouchVM(ctx, params.IDOrName)
if err != nil {
return rpc.NewError("not_found", err.Error())
}
if vm.State != model.VMStateRunning || !system.ProcessRunning(vm.Runtime.PID, vm.Runtime.APISockPath) {
return rpc.NewError("not_running", fmt.Sprintf("vm %s is not running", vm.Name))
}
return marshalResultOrError(api.VMSSHResult{Name: vm.Name, GuestIP: vm.Runtime.GuestIP}, nil)
case "image.list":
images, err := d.store.ListImages(ctx)
return marshalResultOrError(api.ImageListResult{Images: images}, err)
case "image.show":
params, err := rpc.DecodeParams[api.ImageRefParams](req)
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
image, err := d.FindImage(ctx, params.IDOrName)
return marshalResultOrError(api.ImageShowResult{Image: image}, err)
case "image.build":
params, err := rpc.DecodeParams[api.ImageBuildParams](req)
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
image, err := d.BuildImage(ctx, params)
return marshalResultOrError(api.ImageShowResult{Image: image}, err)
case "image.delete":
params, err := rpc.DecodeParams[api.ImageRefParams](req)
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
image, err := d.DeleteImage(ctx, params.IDOrName)
return marshalResultOrError(api.ImageShowResult{Image: image}, err)
default:
return rpc.NewError("unknown_method", req.Method)
}
}
func (d *Daemon) backgroundLoop() {
statsTicker := time.NewTicker(d.config.StatsPollInterval)
staleTicker := time.NewTicker(model.DefaultStaleSweepInterval)
defer statsTicker.Stop()
defer staleTicker.Stop()
for {
select {
case <-d.closing:
return
case <-statsTicker.C:
_ = d.pollStats(context.Background())
case <-staleTicker.C:
_ = d.stopStaleVMs(context.Background())
}
}
}
func (d *Daemon) ensureDefaultImage(ctx context.Context) error {
if d.config.DefaultImageName == "" || d.config.RepoRoot == "" {
return nil
}
if _, err := d.store.GetImageByName(ctx, d.config.DefaultImageName); err == nil {
return nil
}
rootfs := filepath.Join(d.config.RepoRoot, "rootfs-docker.ext4")
kernel := d.config.DefaultKernel
initrd := d.config.DefaultInitrd
if !exists(rootfs) || !exists(kernel) {
return nil
}
id, err := model.NewID()
if err != nil {
return err
}
now := model.Now()
image := model.Image{
ID: id,
Name: d.config.DefaultImageName,
Managed: false,
RootfsPath: rootfs,
KernelPath: kernel,
InitrdPath: initrd,
ModulesDir: d.config.DefaultModulesDir,
PackagesPath: d.config.DefaultPackagesFile,
Docker: strings.Contains(filepath.Base(rootfs), "docker"),
CreatedAt: now,
UpdatedAt: now,
}
return d.store.UpsertImage(ctx, image)
}
func (d *Daemon) reconcile(ctx context.Context) error {
vms, err := d.store.ListVMs(ctx)
if err != nil {
return err
}
for _, vm := range vms {
if vm.State != model.VMStateRunning {
continue
}
if system.ProcessRunning(vm.Runtime.PID, vm.Runtime.APISockPath) {
continue
}
_ = d.cleanupRuntime(ctx, vm, true)
vm.State = model.VMStateStopped
vm.Runtime.State = model.VMStateStopped
vm.Runtime.PID = 0
vm.Runtime.TapDevice = ""
vm.Runtime.APISockPath = ""
vm.Runtime.BaseLoop = ""
vm.Runtime.COWLoop = ""
vm.Runtime.DMName = ""
vm.Runtime.DMDev = ""
vm.UpdatedAt = model.Now()
if err := d.store.UpsertVM(ctx, vm); err != nil {
return err
}
}
return nil
}
func (d *Daemon) FindVM(ctx context.Context, idOrName string) (model.VMRecord, error) {
if idOrName == "" {
return model.VMRecord{}, errors.New("vm id or name is required")
}
if vm, err := d.store.GetVM(ctx, idOrName); err == nil {
return vm, nil
}
vms, err := d.store.ListVMs(ctx)
if err != nil {
return model.VMRecord{}, err
}
matchCount := 0
var match model.VMRecord
for _, vm := range vms {
if strings.HasPrefix(vm.ID, idOrName) || strings.HasPrefix(vm.Name, idOrName) {
match = vm
matchCount++
}
}
if matchCount == 1 {
return match, nil
}
if matchCount > 1 {
return model.VMRecord{}, fmt.Errorf("multiple VMs match %q", idOrName)
}
return model.VMRecord{}, fmt.Errorf("vm %q not found", idOrName)
}
func (d *Daemon) FindImage(ctx context.Context, idOrName string) (model.Image, error) {
if idOrName == "" {
return model.Image{}, errors.New("image id or name is required")
}
if image, err := d.store.GetImageByName(ctx, idOrName); err == nil {
return image, nil
}
if image, err := d.store.GetImageByID(ctx, idOrName); err == nil {
return image, nil
}
images, err := d.store.ListImages(ctx)
if err != nil {
return model.Image{}, err
}
matchCount := 0
var match model.Image
for _, image := range images {
if strings.HasPrefix(image.ID, idOrName) || strings.HasPrefix(image.Name, idOrName) {
match = image
matchCount++
}
}
if matchCount == 1 {
return match, nil
}
if matchCount > 1 {
return model.Image{}, fmt.Errorf("multiple images match %q", idOrName)
}
return model.Image{}, fmt.Errorf("image %q not found", idOrName)
}
func (d *Daemon) TouchVM(ctx context.Context, idOrName string) (model.VMRecord, error) {
d.mu.Lock()
defer d.mu.Unlock()
vm, err := d.FindVM(ctx, idOrName)
if err != nil {
return model.VMRecord{}, err
}
system.TouchNow(&vm)
if err := d.store.UpsertVM(ctx, vm); err != nil {
return model.VMRecord{}, err
}
return vm, nil
}
func marshalResultOrError(v any, err error) rpc.Response {
if err != nil {
return rpc.NewError("operation_failed", err.Error())
}
resp, marshalErr := rpc.NewResult(v)
if marshalErr != nil {
return rpc.NewError("marshal_failed", marshalErr.Error())
}
return resp
}
func exists(path string) bool {
_, err := os.Stat(path)
return err == nil
}