nerve.yaml

@@ -12,15 +12,6 @@ senses:
     timeout: 30s
 
 workflows:
-  develop-sense:
+  restart-gateway:
     concurrency: 1
-    overflow: queue
+    overflow: drop
-  develop-workflow:
-    concurrency: 1
-    overflow: queue
-  solve-issue:
-    concurrency: 1
-    overflow: queue
-  extract-knowledge:
-    concurrency: 1
-    overflow: queue

senses/hermes-gateway-health/migrations/0001_init.sql

@@ -0,0 +1,14 @@
+-- Migration: 0001_init
+-- Creates the hermes_gateway_health table for hermes-gateway-health sense.
+
+CREATE TABLE IF NOT EXISTS hermes_gateway_health (
+  id                    INTEGER PRIMARY KEY AUTOINCREMENT,
+  ts                    INTEGER NOT NULL,
+  alive                 INTEGER NOT NULL,
+  main_pid              INTEGER NOT NULL,
+  rss_bytes             INTEGER NOT NULL,
+  cpu_percent           REAL    NOT NULL,
+  uptime_sec            INTEGER NOT NULL,
+  active_sessions       INTEGER NOT NULL,
+  child_process_count   INTEGER NOT NULL
+);

senses/hermes-gateway-health/migrations/0002_add_http_probe.sql

@@ -0,0 +1,7 @@
+-- Migration: 0002_add_http_probe
+-- HTTP reachability columns for hermes-gateway-health sense.
+
+ALTER TABLE hermes_gateway_health ADD COLUMN http_ok INTEGER NOT NULL DEFAULT 0;
+ALTER TABLE hermes_gateway_health ADD COLUMN http_status_code INTEGER NOT NULL DEFAULT 0;
+ALTER TABLE hermes_gateway_health ADD COLUMN http_latency_ms INTEGER NOT NULL DEFAULT 0;
+ALTER TABLE hermes_gateway_health ADD COLUMN http_error TEXT NOT NULL DEFAULT '';

senses/hermes-gateway-health/src/index.ts

@@ -1,4 +1,6 @@
 import { execFile } from "node:child_process";
+export { hermesGatewayHealth as table } from "./schema.ts";
+
 /** Keep subprocess deadlines slightly under typical sense timeout (30s). */
 const EXEC_TIMEOUT_MS = 25_000;
 
@@ -7,7 +9,7 @@ const HTTP_TIMEOUT_MS = Math.min(23_000, EXEC_TIMEOUT_MS - 2000);
 
 const HTTP_ERROR_MAX_LEN = 256;
 
-/** How many consecutive failures before triggering a restart. */
+/** How many consecutive failures before triggering a restart workflow. */
 const FAILURE_THRESHOLD = 3;
 
 type SenseState = {
@@ -337,7 +339,7 @@ export async function compute(prevState: SenseState) {
   const cooldown = prevState.restartCooldownMs;
   const cooldownElapsed = now - lastRestartTs >= cooldown;
 
-  // --- trigger restart? ---
+  // --- trigger restart workflow? ---
   const shouldRestart =
     consecutiveFailures >= FAILURE_THRESHOLD && cooldownElapsed;
 
@@ -361,9 +363,14 @@ export async function compute(prevState: SenseState) {
     consecutiveFailures,
   };
 
-  const trigger = shouldRestart
+  const workflow = shouldRestart
-    ? { command: "systemctl --user restart hermes-gateway" }
+    ? {
+        name: "restart-gateway",
+        maxRounds: 3,
+        prompt: `Hermes gateway is down (${consecutiveFailures} consecutive failures). Last HTTP error: "${httpError}". systemd active+running: ${systemdActiveRunning}, process alive: ${psOk}. Restart the gateway and verify it comes back.`,
+        dryRun: false,
+      }
     : null;
 
-  return { state: nextState, signal, trigger };
+  return { state: nextState, signal, workflow };
 }

senses/hermes-gateway-health/src/schema.ts

@@ -0,0 +1,17 @@
+import { integer, real, sqliteTable, text } from "drizzle-orm/sqlite-core";
+
+export const hermesGatewayHealth = sqliteTable("hermes_gateway_health", {
+  id: integer("id").primaryKey({ autoIncrement: true }),
+  ts: integer("ts").notNull(),
+  alive: integer("alive").notNull(),
+  mainPid: integer("main_pid").notNull(),
+  rssBytes: integer("rss_bytes").notNull(),
+  cpuPercent: real("cpu_percent").notNull(),
+  uptimeSec: integer("uptime_sec").notNull(),
+  activeSessions: integer("active_sessions").notNull(),
+  childProcessCount: integer("child_process_count").notNull(),
+  httpOk: integer("http_ok").notNull(),
+  httpStatusCode: integer("http_status_code").notNull(),
+  httpLatencyMs: integer("http_latency_ms").notNull(),
+  httpError: text("http_error").notNull(),
+});

workflows/restart-gateway/src/index.ts

@@ -0,0 +1,109 @@
+import { execFile } from "node:child_process";
+import type { RoleResult, ThreadContext, WorkflowDefinition } from "@uncaged/nerve-core";
+import { END } from "@uncaged/nerve-core";
+
+const EXEC_TIMEOUT_MS = 30_000;
+const VERIFY_DELAY_MS = 5_000;
+
+type ExecResult = {
+  exitCode: number;
+  stdout: string;
+  stderr: string;
+};
+
+function exec(file: string, args: string[]): Promise<ExecResult> {
+  return new Promise((resolve) => {
+    execFile(
+      file,
+      args,
+      {
+        encoding: "utf8",
+        timeout: EXEC_TIMEOUT_MS,
+        maxBuffer: 4 * 1024 * 1024,
+      } as Parameters<typeof execFile>[2],
+      (err, stdout, stderr) => {
+        const exitCode =
+          err && typeof (err as NodeJS.ErrnoException).status === "number"
+            ? (err as NodeJS.ErrnoException & { status: number }).status
+            : err ? -1 : 0;
+        resolve({
+          exitCode,
+          stdout: String(stdout ?? ""),
+          stderr: String(stderr ?? ""),
+        });
+      },
+    );
+  });
+}
+
+function sleep(ms: number): Promise<void> {
+  return new Promise((r) => setTimeout(r, ms));
+}
+
+type RestartMeta = {
+  action: string;
+  exitCode: number;
+  output: string;
+};
+
+type VerifyMeta = {
+  alive: boolean;
+  activeState: string;
+  subState: string;
+};
+
+async function restarter(_ctx: ThreadContext): Promise<RoleResult<RestartMeta>> {
+  const r = await exec("systemctl", ["--user", "restart", "hermes-gateway"]);
+  return {
+    content: r.exitCode === 0
+      ? "Gateway restart command succeeded."
+      : `Gateway restart failed (exit ${r.exitCode}): ${r.stderr.trim()}`,
+    meta: {
+      action: "systemctl --user restart hermes-gateway",
+      exitCode: r.exitCode,
+      output: `${r.stdout}\n${r.stderr}`.trim().slice(0, 500),
+    },
+  };
+}
+
+async function verifier(_ctx: ThreadContext): Promise<RoleResult<VerifyMeta>> {
+  // Wait a few seconds for the service to come up
+  await sleep(VERIFY_DELAY_MS);
+
+  const r = await exec("systemctl", [
+    "--user",
+    "--no-pager",
+    "show",
+    "hermes-gateway",
+    "-p", "ActiveState",
+    "-p", "SubState",
+  ]);
+
+  let activeState = "unknown";
+  let subState = "unknown";
+  for (const line of r.stdout.split("\n")) {
+    const t = line.trim();
+    if (t.startsWith("ActiveState=")) activeState = t.slice("ActiveState=".length);
+    if (t.startsWith("SubState=")) subState = t.slice("SubState=".length);
+  }
+
+  const alive = activeState === "active" && subState === "running";
+
+  return {
+    content: alive
+      ? `Gateway recovered: ${activeState} (${subState}).`
+      : `Gateway still down: ${activeState} (${subState}). May need manual intervention.`,
+    meta: { alive, activeState, subState },
+  };
+}
+
+export const workflow: WorkflowDefinition<Record<"restarter", RestartMeta> & Record<"verifier", VerifyMeta>> = {
+  name: "restart-gateway",
+  roles: { restarter, verifier },
+  moderator(ctx) {
+    // Round 0: restart. Round 1: verify. Done.
+    if (ctx.steps.length === 0) return "restarter";
+    if (ctx.steps.length === 1) return "verifier";
+    return END;
+  },
+};