daemon split (4/5): extract *VMService service

Phase 4 of the daemon god-struct refactor. VM lifecycle, create-op
registry, handle cache, disk provisioning, stats polling, ports
query, and the per-VM lock set all move off *Daemon onto *VMService.

Daemon keeps thin forwarders only for FindVM / TouchVM (dispatch
surface) and is otherwise out of VM lifecycle. Lazy-init via
d.vmSvc() mirrors the earlier services so test literals like
\`&Daemon{store: db, runner: r}\` still get a functional service
without spelling one out.

Three small cleanups along the way:

  * preflight helpers (validateStartPrereqs / addBaseStartPrereqs
    / addBaseStartCommandPrereqs / validateWorkDiskResizePrereqs)
    move with the VM methods that call them.
  * cleanupRuntime / rebuildDNS move to *VMService, with
    HostNetwork primitives (findFirecrackerPID, cleanupDMSnapshot,
    killVMProcess, releaseTap, waitForExit, sendCtrlAltDel)
    reached through s.net instead of the hostNet() facade.
  * vsockAgentBinary becomes a package-level function so both
    *Daemon (doctor) and *VMService (preflight) call one entry
    point instead of each owning a forwarder method.

WorkspaceService's peer deps switch from eager method values to
closures — vmSvc() constructs VMService with WorkspaceService as a
peer, so resolving d.vmSvc().FindVM at construction time recursed
through workspaceSvc() → vmSvc(). Closures defer the lookup to call
time.

Pure code motion: build + unit tests green, lint clean. No RPC
surface or lock-ordering changes.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
This commit is contained in:
Thales Maciel 2026-04-20 20:57:05 -03:00
parent c0d456e734
commit 466a7c30c4
No known key found for this signature in database
GPG key ID: 33112E6833C34679
23 changed files with 655 additions and 463 deletions

View file

@ -3,21 +3,18 @@ package daemon
import (
"bufio"
"context"
"database/sql"
"encoding/json"
"errors"
"fmt"
"log/slog"
"net"
"os"
"strings"
"sync"
"time"
"banger/internal/api"
"banger/internal/buildinfo"
"banger/internal/config"
"banger/internal/daemon/opstate"
"banger/internal/model"
"banger/internal/paths"
"banger/internal/rpc"
@ -26,31 +23,23 @@ import (
"banger/internal/vmdns"
)
// Daemon is the composition root: shared infrastructure (store,
// runner, logger, layout, config) plus pointers to the four focused
// services that own behavior. Open wires the services; the dispatch
// loop forwards RPCs to them. No lifecycle / image / workspace /
// networking behavior lives on *Daemon itself — it's wiring.
type Daemon struct {
layout paths.Layout
config model.DaemonConfig
store *store.Store
runner system.CommandRunner
logger *slog.Logger
createVMMu sync.Mutex
createOps opstate.Registry[*vmCreateOperationState]
vmLocks vmLockSet
// workspaceLocks serialises workspace.prepare / workspace.export
// calls on the same VM (two concurrent prepares would clobber each
// other's tar streams). It is a SEPARATE scope from vmLocks so
// slow guest I/O — SSH dial, tar upload, chmod — does not block
// vm stop/delete/restart. See ARCHITECTURE.md.
workspaceLocks vmLockSet
// handles caches per-VM transient kernel/process handles (PID,
// tap device, loop devices, DM name/device). Populated at vm
// start and at daemon startup reconcile; cleared on stop/delete.
// See internal/daemon/vm_handles.go — persistent durable state
// lives in the store, this is rebuildable from a per-VM
// handles.json scratch file and OS inspection.
handles *handleCache
net *HostNetwork
img *ImageService
ws *WorkspaceService
layout paths.Layout
config model.DaemonConfig
store *store.Store
runner system.CommandRunner
logger *slog.Logger
net *HostNetwork
img *ImageService
ws *WorkspaceService
vm *VMService
closing chan struct{}
once sync.Once
pid int
@ -92,7 +81,6 @@ func Open(ctx context.Context) (d *Daemon, err error) {
logger: logger,
closing: closing,
pid: os.Getpid(),
handles: newHandleCache(),
net: newHostNetwork(hostNetworkDeps{
runner: runner,
logger: logger,
@ -134,7 +122,7 @@ func Open(ctx context.Context) (d *Daemon, err error) {
}
used := make([]string, 0, len(vms))
for _, vm := range vms {
if tap := d.vmHandles(vm.ID).TapDevice; tap != "" {
if tap := d.vmSvc().vmHandles(vm.ID).TapDevice; tap != "" {
used = append(used, tap)
}
}
@ -294,28 +282,28 @@ func (d *Daemon) dispatch(ctx context.Context, req rpc.Request) rpc.Response {
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
vm, err := d.CreateVM(ctx, params)
vm, err := d.vmSvc().CreateVM(ctx, params)
return marshalResultOrError(api.VMShowResult{VM: vm}, err)
case "vm.create.begin":
params, err := rpc.DecodeParams[api.VMCreateParams](req)
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
op, err := d.BeginVMCreate(ctx, params)
op, err := d.vmSvc().BeginVMCreate(ctx, params)
return marshalResultOrError(api.VMCreateBeginResult{Operation: op}, err)
case "vm.create.status":
params, err := rpc.DecodeParams[api.VMCreateStatusParams](req)
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
op, err := d.VMCreateStatus(ctx, params.ID)
op, err := d.vmSvc().VMCreateStatus(ctx, params.ID)
return marshalResultOrError(api.VMCreateStatusResult{Operation: op}, err)
case "vm.create.cancel":
params, err := rpc.DecodeParams[api.VMCreateStatusParams](req)
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
err = d.CancelVMCreate(ctx, params.ID)
err = d.vmSvc().CancelVMCreate(ctx, params.ID)
return marshalResultOrError(api.Empty{}, err)
case "vm.list":
vms, err := d.store.ListVMs(ctx)
@ -325,63 +313,63 @@ func (d *Daemon) dispatch(ctx context.Context, req rpc.Request) rpc.Response {
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
vm, err := d.FindVM(ctx, params.IDOrName)
vm, err := d.vmSvc().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)
vm, err := d.vmSvc().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)
vm, err := d.vmSvc().StopVM(ctx, params.IDOrName)
return marshalResultOrError(api.VMShowResult{VM: vm}, err)
case "vm.kill":
params, err := rpc.DecodeParams[api.VMKillParams](req)
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
vm, err := d.KillVM(ctx, params)
vm, err := d.vmSvc().KillVM(ctx, params)
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)
vm, err := d.vmSvc().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)
vm, err := d.vmSvc().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)
vm, err := d.vmSvc().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)
vm, stats, err := d.vmSvc().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)
vm, err := d.vmSvc().FindVM(ctx, params.IDOrName)
if err != nil {
return rpc.NewError("not_found", err.Error())
}
@ -391,11 +379,11 @@ func (d *Daemon) dispatch(ctx context.Context, req rpc.Request) rpc.Response {
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
vm, err := d.TouchVM(ctx, params.IDOrName)
vm, err := d.vmSvc().TouchVM(ctx, params.IDOrName)
if err != nil {
return rpc.NewError("not_found", err.Error())
}
if !d.vmAlive(vm) {
if !d.vmSvc().vmAlive(vm) {
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)
@ -404,21 +392,21 @@ func (d *Daemon) dispatch(ctx context.Context, req rpc.Request) rpc.Response {
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
result, err := d.HealthVM(ctx, params.IDOrName)
result, err := d.vmSvc().HealthVM(ctx, params.IDOrName)
return marshalResultOrError(result, err)
case "vm.ping":
params, err := rpc.DecodeParams[api.VMRefParams](req)
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
result, err := d.PingVM(ctx, params.IDOrName)
result, err := d.vmSvc().PingVM(ctx, params.IDOrName)
return marshalResultOrError(result, err)
case "vm.ports":
params, err := rpc.DecodeParams[api.VMRefParams](req)
if err != nil {
return rpc.NewError("bad_request", err.Error())
}
result, err := d.PortsVM(ctx, params.IDOrName)
result, err := d.vmSvc().PortsVM(ctx, params.IDOrName)
return marshalResultOrError(result, err)
case "vm.workspace.prepare":
params, err := rpc.DecodeParams[api.VMWorkspacePrepareParams](req)
@ -519,14 +507,14 @@ func (d *Daemon) backgroundLoop() {
case <-d.closing:
return
case <-statsTicker.C:
if err := d.pollStats(context.Background()); err != nil && d.logger != nil {
if err := d.vmSvc().pollStats(context.Background()); err != nil && d.logger != nil {
d.logger.Error("background stats poll failed", "error", err.Error())
}
case <-staleTicker.C:
if err := d.stopStaleVMs(context.Background()); err != nil && d.logger != nil {
if err := d.vmSvc().stopStaleVMs(context.Background()); err != nil && d.logger != nil {
d.logger.Error("background stale sweep failed", "error", err.Error())
}
d.pruneVMCreateOperations(time.Now().Add(-10 * time.Minute))
d.vmSvc().pruneVMCreateOperations(time.Now().Add(-10 * time.Minute))
}
}
}
@ -543,18 +531,18 @@ func (d *Daemon) reconcile(ctx context.Context) error {
return op.fail(err)
}
for _, vm := range vms {
if err := d.withVMLockByIDErr(ctx, vm.ID, func(vm model.VMRecord) error {
if err := d.vmSvc().withVMLockByIDErr(ctx, vm.ID, func(vm model.VMRecord) error {
if vm.State != model.VMStateRunning {
// Belt-and-braces: a stopped VM should never have a
// scratch file or a cache entry. Clean up anything
// left by an ungraceful previous daemon crash.
d.clearVMHandles(vm)
d.vmSvc().clearVMHandles(vm)
return nil
}
// Rebuild the in-memory handle cache by loading the per-VM
// scratch file and verifying the firecracker process is
// still alive.
h, alive, err := d.rediscoverHandles(ctx, vm)
h, alive, err := d.vmSvc().rediscoverHandles(ctx, vm)
if err != nil && d.logger != nil {
d.logger.Warn("rediscover handles failed", "vm_id", vm.ID, "error", err.Error())
}
@ -562,54 +550,33 @@ func (d *Daemon) reconcile(ctx context.Context) error {
// claimed. If alive, subsequent vmAlive() calls pass; if
// not, cleanupRuntime needs these handles to know which
// kernel resources (DM / loops / tap) to tear down.
d.setVMHandlesInMemory(vm.ID, h)
d.vmSvc().setVMHandlesInMemory(vm.ID, h)
if alive {
return nil
}
op.stage("stale_vm", vmLogAttrs(vm)...)
_ = d.cleanupRuntime(ctx, vm, true)
_ = d.vmSvc().cleanupRuntime(ctx, vm, true)
vm.State = model.VMStateStopped
vm.Runtime.State = model.VMStateStopped
d.clearVMHandles(vm)
d.vmSvc().clearVMHandles(vm)
vm.UpdatedAt = model.Now()
return d.store.UpsertVM(ctx, vm)
}); err != nil {
return op.fail(err, "vm_id", vm.ID)
}
}
if err := d.rebuildDNS(ctx); err != nil {
if err := d.vmSvc().rebuildDNS(ctx); err != nil {
return op.fail(err)
}
op.done()
return nil
}
// FindVM stays on Daemon as a thin forwarder to the VM service lookup.
// Dispatch code reads the facade directly; tests that pre-date the
// service split keep compiling.
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)
return d.vmSvc().FindVM(ctx, idOrName)
}
// FindImage stays on Daemon as a thin forwarder to the image service
@ -620,52 +587,7 @@ func (d *Daemon) FindImage(ctx context.Context, idOrName string) (model.Image, e
}
func (d *Daemon) TouchVM(ctx context.Context, idOrName string) (model.VMRecord, error) {
return d.withVMLockByRef(ctx, idOrName, func(vm model.VMRecord) (model.VMRecord, error) {
system.TouchNow(&vm)
if err := d.store.UpsertVM(ctx, vm); err != nil {
return model.VMRecord{}, err
}
return vm, nil
})
}
func (d *Daemon) withVMLockByRef(ctx context.Context, idOrName string, fn func(model.VMRecord) (model.VMRecord, error)) (model.VMRecord, error) {
vm, err := d.FindVM(ctx, idOrName)
if err != nil {
return model.VMRecord{}, err
}
return d.withVMLockByID(ctx, vm.ID, fn)
}
func (d *Daemon) withVMLockByID(ctx context.Context, id string, fn func(model.VMRecord) (model.VMRecord, error)) (model.VMRecord, error) {
if strings.TrimSpace(id) == "" {
return model.VMRecord{}, errors.New("vm id is required")
}
unlock := d.lockVMID(id)
defer unlock()
vm, err := d.store.GetVMByID(ctx, id)
if err != nil {
if errors.Is(err, sql.ErrNoRows) {
return model.VMRecord{}, fmt.Errorf("vm %q not found", id)
}
return model.VMRecord{}, err
}
return fn(vm)
}
func (d *Daemon) withVMLockByIDErr(ctx context.Context, id string, fn func(model.VMRecord) error) error {
_, err := d.withVMLockByID(ctx, id, func(vm model.VMRecord) (model.VMRecord, error) {
if err := fn(vm); err != nil {
return model.VMRecord{}, err
}
return vm, nil
})
return err
}
func (d *Daemon) lockVMID(id string) func() {
return d.vmLocks.lock(id)
return d.vmSvc().TouchVM(ctx, idOrName)
}
func marshalResultOrError(v any, err error) rpc.Response {