Phase 1: webhook handler + systemd unit + flock in dev-task

webhook/agent-webhook.service

@@ -0,0 +1,16 @@
+[Unit]
+Description=agent-coding-empire webhook handler
+After=network-online.target
+Wants=network-online.target
+
+[Service]
+Type=simple
+ExecStart=/usr/bin/python3 /usr/local/bin/agent-webhook.py
+Restart=on-failure
+RestartSec=3
+StandardOutput=journal
+StandardError=journal
+Environment=PYTHONUNBUFFERED=1
+
+[Install]
+WantedBy=multi-user.target

webhook/handler.py

@@ -0,0 +1,128 @@
+#!/usr/bin/env python3
+"""
+Gitea webhook handler — agent-coding-empire dispatcher.
+
+Listens on TCP :18790 for Gitea webhook deliveries. When an issue acquires the
+label "agent:assign" (or is opened with that label), SSH-triggers dev-task.sh
+on dev-01 (192.168.1.29).
+
+Verifies the X-Gitea-Signature HMAC header against WEBHOOK_SECRET from
+/etc/agent/webhook-secret.
+
+This is a deliberately tiny single-file service. It uses stdlib only.
+"""
+import hashlib
+import hmac
+import http.server
+import json
+import logging
+import os
+import socketserver
+import subprocess
+import threading
+import time
+from pathlib import Path
+
+LISTEN_HOST = os.environ.get("LISTEN_HOST", "0.0.0.0")
+LISTEN_PORT = int(os.environ.get("LISTEN_PORT", "18790"))
+SECRET_FILE = Path(os.environ.get("WEBHOOK_SECRET_FILE", "/etc/agent/webhook-secret"))
+DEV_HOST    = os.environ.get("DEV_HOST", "agent@192.168.1.29")
+SSH_KEY     = os.environ.get("SSH_KEY", "/root/.ssh/id_ed25519_pve")
+LABEL       = os.environ.get("AGENT_LABEL", "agent:assign")
+LOG_DIR     = Path(os.environ.get("HANDLER_LOG_DIR", "/var/log/agent-webhook"))
+
+logging.basicConfig(
+    level=logging.INFO,
+    format="%(asctime)s %(levelname)s %(message)s",
+)
+log = logging.getLogger("webhook")
+
+SECRET = SECRET_FILE.read_text().strip()
+
+
+def verify_signature(body: bytes, sig_header: str) -> bool:
+    if not sig_header:
+        return False
+    mac = hmac.new(SECRET.encode(), body, hashlib.sha256).hexdigest()
+    return hmac.compare_digest(mac, sig_header)
+
+
+def should_dispatch(event: str, payload: dict) -> tuple[bool, str | None, int | None]:
+    """Decide if this delivery should kick off a dev-task. Returns (yes, repo, issue#)."""
+    if event != "issues":
+        return False, None, None
+    action = payload.get("action", "")
+    issue = payload.get("issue", {})
+    repo = payload.get("repository", {}).get("full_name")
+    number = issue.get("number")
+    labels = [l.get("name", "") for l in issue.get("labels", [])]
+    if action == "opened" and LABEL in labels:
+        return True, repo, number
+    if action == "label_updated" and LABEL in labels:
+        # Gitea fires label_updated for both add and remove; we only care about presence
+        return True, repo, number
+    return False, None, None
+
+
+def dispatch(repo: str, issue: int):
+    """SSH into dev-01 and fire dev-task in the background."""
+    LOG_DIR.mkdir(parents=True, exist_ok=True)
+    fn = LOG_DIR / f"dispatch-{repo.replace('/', '_')}-issue-{issue}-{int(time.time())}.log"
+    log.info("dispatching dev-task for %s#%d -> %s", repo, issue, fn)
+    cmd = [
+        "ssh", "-i", SSH_KEY,
+        "-o", "BatchMode=yes",
+        "-o", "StrictHostKeyChecking=accept-new",
+        DEV_HOST,
+        f"PATH=$HOME/.local/bin:/usr/local/bin:$PATH "
+        f"nohup /usr/local/bin/dev-task.sh '{repo}' {issue} "
+        f">>/var/agent/logs/dispatch-issue-{issue}.log 2>&1 &"
+    ]
+    with open(fn, "wb") as f:
+        rc = subprocess.run(cmd, stdout=f, stderr=subprocess.STDOUT).returncode
+    log.info("dispatch ssh rc=%d", rc)
+
+
+class WebhookHandler(http.server.BaseHTTPRequestHandler):
+    def do_POST(self):
+        n = int(self.headers.get("Content-Length", "0"))
+        body = self.rfile.read(n)
+        sig  = self.headers.get("X-Gitea-Signature", "")
+        ev   = self.headers.get("X-Gitea-Event", "")
+
+        if not verify_signature(body, sig):
+            log.warning("bad signature for event=%s", ev)
+            self.send_response(401); self.end_headers(); self.wfile.write(b"bad sig\n"); return
+
+        try:
+            payload = json.loads(body)
+        except json.JSONDecodeError:
+            self.send_response(400); self.end_headers(); self.wfile.write(b"bad json\n"); return
+
+        ok, repo, issue = should_dispatch(ev, payload)
+        if ok and repo and issue is not None:
+            threading.Thread(target=dispatch, args=(repo, issue), daemon=True).start()
+            self.send_response(202); self.end_headers()
+            self.wfile.write(b"dispatched\n")
+        else:
+            self.send_response(200); self.end_headers()
+            self.wfile.write(b"ignored\n")
+
+    def do_GET(self):
+        if self.path == "/healthz":
+            self.send_response(200); self.end_headers(); self.wfile.write(b"ok\n")
+        else:
+            self.send_response(404); self.end_headers()
+
+    def log_message(self, fmt, *args):
+        log.info("%s - %s", self.address_string(), fmt % args)
+
+
+class ThreadedServer(socketserver.ThreadingMixIn, http.server.HTTPServer):
+    daemon_threads = True
+
+
+if __name__ == "__main__":
+    log.info("agent-webhook listening on %s:%d, target=%s, label=%s",
+             LISTEN_HOST, LISTEN_PORT, DEV_HOST, LABEL)
+    ThreadedServer((LISTEN_HOST, LISTEN_PORT), WebhookHandler).serve_forever()