refactor: extract process management to shell/process package

Extrae toda la lógica de gestión de procesos (scan, start, stop, kill, stats,
log tail) de cmd/agentctl/main.go a shell/process/manager.go como paquete
reutilizable siguiendo el patrón impure shell del proyecto.

agentctl queda como thin wrapper sobre process.Manager — misma funcionalidad,
mismo comportamiento. El nuevo paquete será compartido por el TUI dashboard.

Añade funcionalidad nueva al Manager: Stats() para métricas de /proc,
LogTail() para últimas N líneas, Stop() con espera graceful + SIGKILL fallback.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
This commit is contained in:
2026-03-04 19:38:19 +00:00
parent 791cea7db0
commit 00dac8b77f
2 changed files with 373 additions and 187 deletions
+304
View File
@@ -0,0 +1,304 @@
// Package process manages agent processes: discovery, start, stop, kill, stats.
// This is the impure shell layer — all I/O happens here.
package process
import (
"bufio"
"fmt"
"os"
"os/exec"
"path/filepath"
"strconv"
"strings"
"syscall"
"time"
"github.com/enmanuel/agents/internal/config"
)
// AgentInfo holds metadata about an agent parsed from its config.
type AgentInfo struct {
ID string
Name string
Version string
Desc string
ConfigPath string
Enabled bool
}
// AgentStatus combines agent metadata with runtime state.
type AgentStatus struct {
AgentInfo
Running bool
PID int
}
// ProcessStats holds resource usage for a running process.
type ProcessStats struct {
PID int
UptimeSecs int64
MemRSSKB int64
CPUPct float64
LogBytes int64
}
// Manager handles agent process lifecycle.
type Manager struct {
runDir string
agentsGlob string
binPath string
}
// NewManager creates a Manager. binPath can be empty for auto-detection.
func NewManager(runDir, agentsGlob, binPath string) *Manager {
return &Manager{runDir: runDir, agentsGlob: agentsGlob, binPath: binPath}
}
// Scan discovers all agents from config files.
func (m *Manager) Scan() ([]AgentInfo, error) {
matches, err := filepath.Glob(m.agentsGlob)
if err != nil {
return nil, err
}
var agents []AgentInfo
for _, path := range matches {
cfg, err := config.LoadMeta(path)
if err != nil {
continue
}
agents = append(agents, AgentInfo{
ID: cfg.Agent.ID,
Name: cfg.Agent.Name,
Version: cfg.Agent.Version,
Desc: cfg.Agent.Description,
ConfigPath: path,
Enabled: cfg.Agent.Enabled,
})
}
return agents, nil
}
// Status returns the runtime status for a single agent.
func (m *Manager) Status(info AgentInfo) AgentStatus {
pid := m.readPID(info.ID)
running := pid > 0 && m.isAlive(pid)
return AgentStatus{AgentInfo: info, Running: running, PID: pid}
}
// StatusAll returns status for every discovered agent.
func (m *Manager) StatusAll() ([]AgentStatus, error) {
agents, err := m.Scan()
if err != nil {
return nil, err
}
statuses := make([]AgentStatus, len(agents))
for i, a := range agents {
statuses[i] = m.Status(a)
}
return statuses, nil
}
// Start launches an agent process in the background.
func (m *Manager) Start(info AgentInfo) error {
if err := os.MkdirAll(m.runDir, 0o755); err != nil {
return fmt.Errorf("create run dir: %w", err)
}
logFile, err := os.OpenFile(m.logPath(info.ID), os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0o644)
if err != nil {
return fmt.Errorf("open log: %w", err)
}
bin := m.resolvedBin()
var cmd *exec.Cmd
if strings.HasPrefix(bin, "go run") {
cmd = exec.Command("go", "run", "./cmd/launcher", "-c", info.ConfigPath)
} else {
cmd = exec.Command(bin, "-c", info.ConfigPath)
}
cmd.Stdout = logFile
cmd.Stderr = logFile
cmd.SysProcAttr = &syscall.SysProcAttr{Setsid: true}
if err := cmd.Start(); err != nil {
logFile.Close()
return fmt.Errorf("exec: %w", err)
}
if err := os.WriteFile(m.pidPath(info.ID), []byte(strconv.Itoa(cmd.Process.Pid)), 0o644); err != nil {
return fmt.Errorf("write PID: %w", err)
}
go func() { _ = cmd.Wait() }()
return nil
}
// Stop sends SIGTERM, waits up to 5s, then SIGKILL if needed.
func (m *Manager) Stop(id string) error {
pid := m.readPID(id)
if pid == 0 || !m.isAlive(pid) {
return fmt.Errorf("agent %q is not running", id)
}
if err := syscall.Kill(pid, syscall.SIGTERM); err != nil {
return fmt.Errorf("SIGTERM: %w", err)
}
// Wait up to 5 seconds for graceful shutdown.
for i := 0; i < 10; i++ {
if !m.isAlive(pid) {
m.removePID(id)
return nil
}
time.Sleep(500 * time.Millisecond)
}
// Force kill.
if m.isAlive(pid) {
_ = syscall.Kill(pid, syscall.SIGKILL)
}
m.removePID(id)
return nil
}
// Kill sends SIGKILL immediately.
func (m *Manager) Kill(id string) error {
pid := m.readPID(id)
if pid == 0 || !m.isAlive(pid) {
return fmt.Errorf("agent %q is not running", id)
}
err := syscall.Kill(pid, syscall.SIGKILL)
m.removePID(id)
return err
}
// Stats gathers resource usage for a running agent from /proc.
func (m *Manager) Stats(id string) (ProcessStats, error) {
pid := m.readPID(id)
if pid == 0 || !m.isAlive(pid) {
return ProcessStats{}, fmt.Errorf("agent %q is not running", id)
}
s := ProcessStats{PID: pid}
// Uptime from /proc/<pid>/stat
if data, err := os.ReadFile(fmt.Sprintf("/proc/%d/stat", pid)); err == nil {
fields := strings.Fields(string(data))
if len(fields) > 21 {
startTicks, _ := strconv.ParseInt(fields[21], 10, 64)
clkTck := int64(100) // sysconf(_SC_CLK_TCK) is 100 on Linux
if raw, err := os.ReadFile("/proc/stat"); err == nil {
for _, line := range strings.Split(string(raw), "\n") {
if strings.HasPrefix(line, "btime ") {
btime, _ := strconv.ParseInt(strings.Fields(line)[1], 10, 64)
procStart := btime + startTicks/clkTck
s.UptimeSecs = time.Now().Unix() - procStart
break
}
}
}
}
}
// RSS from /proc/<pid>/status
if data, err := os.ReadFile(fmt.Sprintf("/proc/%d/status", pid)); err == nil {
for _, line := range strings.Split(string(data), "\n") {
if strings.HasPrefix(line, "VmRSS:") {
fields := strings.Fields(line)
if len(fields) >= 2 {
s.MemRSSKB, _ = strconv.ParseInt(fields[1], 10, 64)
}
break
}
}
}
// CPU% from ps (simpler than calculating from /proc/stat deltas)
if out, err := exec.Command("ps", "-p", strconv.Itoa(pid), "-o", "pcpu=").Output(); err == nil {
s.CPUPct, _ = strconv.ParseFloat(strings.TrimSpace(string(out)), 64)
}
// Log file size
if info, err := os.Stat(m.logPath(id)); err == nil {
s.LogBytes = info.Size()
}
return s, nil
}
// LogTail returns the last N lines of an agent's log.
func (m *Manager) LogTail(id string, lines int) ([]string, error) {
f, err := os.Open(m.logPath(id))
if err != nil {
return nil, fmt.Errorf("open log: %w", err)
}
defer f.Close()
// Read all lines and keep last N. For large files a reverse scanner
// would be better, but agent logs are typically small.
var all []string
scanner := bufio.NewScanner(f)
scanner.Buffer(make([]byte, 0, 64*1024), 1024*1024)
for scanner.Scan() {
all = append(all, scanner.Text())
}
if err := scanner.Err(); err != nil {
return nil, err
}
if len(all) > lines {
all = all[len(all)-lines:]
}
return all, nil
}
// IsRunning checks if an agent process is alive.
func (m *Manager) IsRunning(id string) bool {
pid := m.readPID(id)
return pid > 0 && m.isAlive(pid)
}
// ReadPID returns the PID from the PID file, or 0.
func (m *Manager) ReadPID(id string) int {
return m.readPID(id)
}
// PidPath returns the path to the PID file for an agent.
func (m *Manager) PidPath(id string) string { return m.pidPath(id) }
// LogPath returns the path to the log file for an agent.
func (m *Manager) LogPath(id string) string { return m.logPath(id) }
// ── internal helpers ─────────────────────────────────────────────────────
func (m *Manager) pidPath(id string) string { return filepath.Join(m.runDir, id+".pid") }
func (m *Manager) logPath(id string) string { return filepath.Join(m.runDir, id+".log") }
func (m *Manager) readPID(id string) int {
raw, err := os.ReadFile(m.pidPath(id))
if err != nil {
return 0
}
pid, _ := strconv.Atoi(strings.TrimSpace(string(raw)))
return pid
}
func (m *Manager) isAlive(pid int) bool {
return syscall.Kill(pid, 0) == nil
}
func (m *Manager) removePID(id string) {
_ = os.Remove(m.pidPath(id))
}
func (m *Manager) resolvedBin() string {
if m.binPath != "" {
return m.binPath
}
if _, err := os.Stat("bin/launcher"); err == nil {
return "bin/launcher"
}
return "go run ./cmd/launcher"
}