Files

448 lines
11 KiB
Go

// Package nodecontrol exposes fixed host operations over a local Unix socket.
package nodecontrol
import (
"context"
"crypto/rand"
"encoding/hex"
"encoding/json"
"errors"
"fmt"
"io"
"net"
"net/http"
"net/netip"
"os"
"path/filepath"
"regexp"
"sort"
"strings"
"sync"
"time"
)
const Socket = "/run/felis-node-control/control.sock"
const MaxLog = 64 << 10
var ErrBusy = errors.New("a node operation is already running")
var ErrNotFound = errors.New("node operation not found")
var namePattern = regexp.MustCompile(`^[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?$`)
var targetPattern = regexp.MustCompile(`^[a-zA-Z0-9][a-zA-Z0-9_.@:-]{0,252}$`)
var idPattern = regexp.MustCompile(`^[a-f0-9]{32}$`)
func validNodeName(name string) bool {
if len(name) > 63 {
return false
}
for _, label := range strings.Split(name, ".") {
if !namePattern.MatchString(label) {
return false
}
}
return true
}
type Request struct {
Action string `json:"action"`
Name string `json:"name,omitempty"`
SSHTarget string `json:"sshTarget,omitempty"`
ExternalIP string `json:"externalIP,omitempty"`
Peers []string `json:"peers,omitempty"`
ConfirmMaintenance bool `json:"confirmMaintenance"`
}
func (r Request) Validate() error {
if !r.ConfirmMaintenance {
return errors.New("maintenance impact confirmation is required")
}
switch r.Action {
case "join", "approve":
if !validNodeName(r.Name) || !targetPattern.MatchString(r.SSHTarget) {
return errors.New("invalid worker name or SSH target")
}
case "enable":
default:
return errors.New("unsupported node operation")
}
if r.Action != "approve" {
if a, err := netip.ParseAddr(r.ExternalIP); err != nil || a.IsUnspecified() || a.IsLoopback() || a.IsMulticast() || a.Zone() != "" {
return errors.New("a fixed node IP is required")
}
}
for _, peer := range r.Peers {
p, err := netip.ParsePrefix(peer)
if err != nil || p.Bits() != p.Addr().BitLen() || p.Addr().IsLoopback() || p.Addr().IsMulticast() || p.Addr().IsUnspecified() {
return errors.New("peer addresses must use exact /32 or /128 prefixes")
}
}
if len(r.Peers) > 100 {
return errors.New("too many peer addresses")
}
return nil
}
type Task struct {
ID string `json:"id"`
Request Request `json:"request"`
Actor string `json:"actor"`
State string `json:"state"`
Stage string `json:"stage"`
StartedAt time.Time `json:"startedAt"`
FinishedAt *time.Time `json:"finishedAt,omitempty"`
Error string `json:"error,omitempty"`
Log string `json:"log,omitempty"`
}
type Executor func(context.Context, Request, func(string) error, io.Writer) error
type Manager struct {
dir string
execute Executor
mu sync.Mutex
tasks map[string]Task
active string
ctx context.Context
wg sync.WaitGroup
}
func Open(ctx context.Context, dir string, execute Executor) (*Manager, error) {
if err := os.MkdirAll(dir, 0700); err != nil {
return nil, err
}
m := &Manager{dir: dir, execute: execute, tasks: map[string]Task{}, ctx: ctx}
paths, err := filepath.Glob(filepath.Join(dir, "*.json"))
if err != nil {
return nil, err
}
for _, path := range paths {
raw, err := os.ReadFile(path)
if err != nil {
return nil, err
}
var t Task
if err = json.Unmarshal(raw, &t); err != nil {
return nil, fmt.Errorf("read node task: %w", err)
}
if !idPattern.MatchString(t.ID) || filepath.Base(path) != t.ID+".json" {
return nil, errors.New("invalid stored task ID")
}
if t.State == "running" {
t.State, t.Error = "failed", "Host execution service restarted. Verify the host state before retrying."
now := time.Now().UTC()
t.FinishedAt = &now
if err = m.persist(t); err != nil {
return nil, err
}
}
m.tasks[t.ID] = t
}
return m, nil
}
func (m *Manager) persist(t Task) error {
t.Log = ""
raw, err := json.Marshal(t)
if err != nil {
return err
}
path := filepath.Join(m.dir, t.ID+".json")
f, err := os.OpenFile(path+".tmp", os.O_CREATE|os.O_TRUNC|os.O_WRONLY, 0600)
if err != nil {
return err
}
if _, err = f.Write(raw); err == nil {
err = f.Sync()
}
closeErr := f.Close()
if err != nil {
return err
}
if closeErr != nil {
return closeErr
}
if err = os.Rename(path+".tmp", path); err != nil {
return err
}
d, err := os.Open(m.dir)
if err != nil {
return err
}
defer d.Close()
return d.Sync()
}
func (m *Manager) List() []Task {
m.mu.Lock()
defer m.mu.Unlock()
out := make([]Task, 0, len(m.tasks))
for _, t := range m.tasks {
out = append(out, t)
}
sort.Slice(out, func(i, j int) bool { return out[i].StartedAt.After(out[j].StartedAt) })
if len(out) > 100 {
out = out[:100]
}
return out
}
func (m *Manager) Get(id string) (Task, error) {
m.mu.Lock()
defer m.mu.Unlock()
t, ok := m.tasks[id]
if !ok {
return Task{}, ErrNotFound
}
f, err := os.Open(filepath.Join(m.dir, id+".log"))
if errors.Is(err, os.ErrNotExist) {
return t, nil
}
if err != nil {
return t, err
}
defer f.Close()
info, err := f.Stat()
if err != nil {
return t, err
}
if info.Size() > MaxLog {
if _, err = f.Seek(-MaxLog, io.SeekEnd); err != nil {
return t, err
}
}
raw, err := io.ReadAll(f)
t.Log = string(raw)
return t, err
}
func (m *Manager) Start(r Request, actor string) (Task, error) {
if err := r.Validate(); err != nil {
return Task{}, err
}
m.mu.Lock()
defer m.mu.Unlock()
if m.active != "" {
return Task{}, ErrBusy
}
if err := m.ctx.Err(); err != nil {
return Task{}, err
}
var id [16]byte
if _, err := rand.Read(id[:]); err != nil {
return Task{}, err
}
t := Task{ID: hex.EncodeToString(id[:]), Request: r, Actor: actor, State: "running", Stage: "preflight", StartedAt: time.Now().UTC()}
if err := m.persist(t); err != nil {
return Task{}, err
}
m.tasks[t.ID] = t
m.active = t.ID
m.wg.Add(1)
go m.run(t)
return t, nil
}
func (m *Manager) run(t Task) {
defer m.wg.Done()
ctx, cancel := context.WithTimeout(m.ctx, 45*time.Minute)
defer cancel()
log, err := os.OpenFile(filepath.Join(m.dir, t.ID+".log"), os.O_CREATE|os.O_RDWR|os.O_APPEND, 0600)
if err == nil {
stage := func(s string) error {
m.mu.Lock()
defer m.mu.Unlock()
t.Stage = s
if err := m.persist(t); err != nil {
return err
}
m.tasks[t.ID] = t
_, err := fmt.Fprintln(log, "[felis]", s)
return err
}
err = m.execute(ctx, t.Request, stage, &boundedLog{file: log})
if ctx.Err() != nil {
err = ctx.Err()
}
if closeErr := log.Close(); err == nil {
err = closeErr
}
}
m.mu.Lock()
defer m.mu.Unlock()
now := time.Now().UTC()
t.FinishedAt = &now
t.State = "succeeded"
if err != nil {
t.State = "failed"
t.Error = err.Error()
if errors.Is(err, context.DeadlineExceeded) {
t.Error = "Host operation exceeded the 45-minute execution limit. Verify the host state before retrying."
}
if errors.Is(err, context.Canceled) {
t.Error = "Host operation was interrupted. Verify the host state before retrying."
}
}
if persistErr := m.persist(t); persistErr != nil {
t.State = "failed"
t.Error = "Task result persistence failed: " + persistErr.Error()
}
m.tasks[t.ID] = t
m.active = ""
for len(m.tasks) > 100 {
oldest := ""
for id, candidate := range m.tasks {
if id == t.ID {
continue
}
if oldest == "" || candidate.StartedAt.Before(m.tasks[oldest].StartedAt) {
oldest = id
}
}
if oldest != "" {
if err := os.Remove(filepath.Join(m.dir, oldest+".json")); err == nil {
os.Remove(filepath.Join(m.dir, oldest+".log"))
delete(m.tasks, oldest)
} else {
break
}
}
}
}
func (m *Manager) Wait() { m.wg.Wait() }
// Handler is reachable only through the root-owned socket mounted into felis-api.
func (m *Manager) Handler() http.Handler {
mux := http.NewServeMux()
mux.HandleFunc("GET /tasks", func(w http.ResponseWriter, r *http.Request) { json.NewEncoder(w).Encode(m.List()) })
mux.HandleFunc("GET /tasks/{id}", func(w http.ResponseWriter, r *http.Request) {
t, err := m.Get(r.PathValue("id"))
if err != nil {
http.Error(w, err.Error(), 404)
return
}
json.NewEncoder(w).Encode(t)
})
mux.HandleFunc("POST /tasks", func(w http.ResponseWriter, r *http.Request) {
var body struct {
Request Request `json:"request"`
Actor string `json:"actor"`
}
dec := json.NewDecoder(http.MaxBytesReader(w, r.Body, 8192))
dec.DisallowUnknownFields()
if err := dec.Decode(&body); err != nil {
http.Error(w, "invalid task request", 400)
return
}
if err := dec.Decode(&struct{}{}); err != io.EOF {
http.Error(w, "invalid trailing task data", 400)
return
}
if err := body.Request.Validate(); err != nil {
http.Error(w, err.Error(), 400)
return
}
t, err := m.Start(body.Request, body.Actor)
if err != nil {
code := 500
if errors.Is(err, ErrBusy) {
code = 409
}
http.Error(w, err.Error(), code)
return
}
w.WriteHeader(http.StatusAccepted)
json.NewEncoder(w).Encode(t)
})
return mux
}
type Client struct{ http *http.Client }
func NewClient(socket string) *Client {
return &Client{http: &http.Client{Timeout: 10 * time.Second, Transport: &http.Transport{DialContext: func(ctx context.Context, _, _ string) (net.Conn, error) {
return (&net.Dialer{}).DialContext(ctx, "unix", socket)
}}}}
}
func (c *Client) call(ctx context.Context, method, path string, body any, out any) error {
var reader io.Reader
if body != nil {
raw, err := json.Marshal(body)
if err != nil {
return err
}
reader = strings.NewReader(string(raw))
}
req, err := http.NewRequestWithContext(ctx, method, "http://node-control"+path, reader)
if err != nil {
return err
}
res, err := c.http.Do(req)
if err != nil {
return err
}
defer res.Body.Close()
if res.StatusCode == 409 {
return ErrBusy
}
if res.StatusCode == 404 {
return ErrNotFound
}
if res.StatusCode >= 400 {
return fmt.Errorf("host service returned HTTP %d", res.StatusCode)
}
return json.NewDecoder(io.LimitReader(res.Body, 1<<20)).Decode(out)
}
func (c *Client) List(ctx context.Context) ([]Task, error) {
var out []Task
err := c.call(ctx, "GET", "/tasks", nil, &out)
return out, err
}
func (c *Client) Get(ctx context.Context, id string) (Task, error) {
if !idPattern.MatchString(id) {
return Task{}, ErrNotFound
}
var out Task
err := c.call(ctx, "GET", "/tasks/"+id, nil, &out)
return out, err
}
func (c *Client) Start(ctx context.Context, r Request, actor string) (Task, error) {
var out Task
err := c.call(ctx, "POST", "/tasks", map[string]any{"request": r, "actor": actor}, &out)
return out, err
}
// Bound disk use while retaining the most recent output of long builds.
type boundedLog struct {
file *os.File
mu sync.Mutex
}
func (w *boundedLog) Write(p []byte) (int, error) {
w.mu.Lock()
defer w.mu.Unlock()
const limit = 4 << 20
info, err := w.file.Stat()
if err != nil {
return 0, err
}
if info.Size()+int64(len(p)) > limit {
n := int64(MaxLog)
if info.Size() < n {
n = info.Size()
}
tail := make([]byte, n)
if _, err = w.file.ReadAt(tail, info.Size()-n); err != nil {
return 0, err
}
if err = w.file.Truncate(0); err != nil {
return 0, err
}
if _, err = w.file.Write(tail); err != nil {
return 0, err
}
}
original := len(p)
if len(p) > limit {
p = p[len(p)-limit:]
}
_, err = w.file.Write(p)
if err != nil {
return 0, err
}
return original, nil
}