Files
zero/internal/daemon/backoff_test.go
KRATOS 135e3c5657 feat(daemon): zero daemon — worker pool + session supervisor over a local control socket (#203)
* feat(daemon): add `zero daemon` — worker pool + session supervisor over a local control socket

Adds internal/daemon + `zero daemon start|stop|status|run|attach`: a long-running
local service that supervises a pool of headless `zero exec` workers and routes
multiple agent sessions to them over an owner-only Unix-domain control socket.
Additive — interactive and one-shot exec are unchanged.

Reuses zero's building blocks:
- internal/background: ConfigureChildProcessGroup (process-group setup) +
  TerminateProcess (cross-platform terminate) for worker kill/drain. The pool
  does its own os/exec and uses background only for those helpers.
- internal/streamjson: the worker speaks stream-json on stdout; the daemon
  forwards those lines to clients.
- internal/cli exec: a worker is `zero exec --output-format stream-json`.

Pieces (reimplemented in Go from a reference daemon):
- protocol.go: framed control codec — 4-byte BE length + 1 kind byte, 1 MiB cap,
  JSON control messages, version negotiation.
- pool.go + backoff.go: bounded worker pool — at-least-once dispatch with
  exponential backoff+jitter retry capped by MaxAttempts, EXIT_TEMPFAIL(75)/
  EXIT_PERMANENT(76) handling, graceful drain + kill-timeout. zero's exec is
  one-shot, so workers are on-demand (one session per worker = the lease), not
  warm long-lived slots (a persistent worker mode is a follow-up).
- session.go: SessionManager — sessionID->worker routing, lease (one active
  request per worker), queue when the pool is full, per-session output buffer for
  attach + metrics.
- server.go + lock.go + socket.go + paths.go: single-instance PID-file lock with
  stale-lock (dead-PID) recovery, status file, owner-only socket, accept loop;
  cleans up lock/socket/status on exit.
- launcher.go: production worker launcher. client.go: control-socket client.

Security model:
- Control socket is LOCAL-ONLY (AF_UNIX loopback file, never a TCP port) and
  owner-only: socket 0600 + parent dir 0700 on POSIX (Windows relies on the
  per-user profile ACL; a dedicated pipe ACL is a follow-up).
- Workers stay sandboxed: the launcher SCRUBS the sandbox re-entrancy markers
  (ZERO_SANDBOXED / ZERO_SANDBOX_BACKEND) from each worker's env so the worker
  re-establishes its OWN sandbox instead of inheriting a pass-through plan, while
  propagating the rest of the policy config/env. The daemon never bypasses the
  sandbox.
- Control frames over the 1 MiB cap are rejected before allocation.

Robustness: a crashed worker never takes down the daemon (backoff+jitter retry,
MaxAttempts cap, EXIT_PERMANENT stops retry); drain gives a grace window then
force-kills stragglers; a stale lock from an unclean exit is reclaimed.

Out of scope (follow-up): remote session-linking; warm pre-spawned persistent
workers; Windows named-pipe ACL.

Tests: protocol round-trip + oversize/unknown-kind rejection; backoff bounds;
pool spawn/retry-backoff/permanent/cap/queue/drain; session lease/route/queue/
attach; lock single-instance + stale recovery; launcher env-scrub (incl. an
end-to-end check that the spawned worker process receives scrubbed env); server
e2e start->run->stream-json->status->attach->stop with a fake worker; CLI
usage/validation/not-running paths. Live-verified start/status/stop (0600 socket,
0700 dir, file cleanup). Platform files behind explicit //go:build tags.

* daemon: address review — help listing, extra-arg rejection, lock write error, bounded sessions

- cli/app.go: list `daemon` in `zero --help` so the command is discoverable.
- cli/daemon: `stop`/`status` reject extra arguments; `attach` rejects more than
  one session id (fail fast on typos instead of silently ignoring tokens).
- daemon/lock: check the PID fmt.Fprintf error — a partial/failed write would
  leave a malformed lock file that another process reads as stale and wrongly
  reclaims, breaking the single-instance guarantee; on write failure remove the
  file and return the error.
- daemon/session: bound the registry with MaxSessions (default 256) — evict the
  oldest FINISHED sessions once past the cap so a long-running daemon doesn't
  accumulate sessions without limit; running/queued sessions are never evicted, so
  attach-after-finish for recent sessions is preserved.

Tests: CLI extra-arg rejection; finished-over-cap eviction + running-never-evicted.
Gates: gofmt, vet, build, test (incl -race), staticcheck (no new), govulncheck (0),
deadcode (no new), GOOS=linux+windows cross-compile.
2026-06-14 22:16:37 +05:30

39 lines
869 B
Go

package daemon
import (
"testing"
"time"
)
func TestBackoffBaseExponentialAndCap(t *testing.T) {
cases := []struct {
attempt int
want time.Duration
}{
{0, 1 * time.Second},
{1, 2 * time.Second},
{2, 4 * time.Second},
{3, 8 * time.Second},
{20, backoffCap}, // far past the cap
}
for _, tc := range cases {
if got := backoffBase(tc.attempt); got != tc.want {
t.Fatalf("backoffBase(%d) = %s, want %s", tc.attempt, got, tc.want)
}
}
}
func TestBackoffWithJitterBounds(t *testing.T) {
for attempt := 1; attempt <= 6; attempt++ {
base := backoffBase(attempt)
lo := time.Duration(float64(base) * 0.5)
hi := time.Duration(float64(base) * 1.5)
for i := 0; i < 200; i++ {
got := BackoffWithJitter(attempt)
if got < lo || got >= hi {
t.Fatalf("BackoffWithJitter(%d) = %s, want in [%s,%s)", attempt, got, lo, hi)
}
}
}
}