"""Generic webhook platform adapter.
Runs an aiohttp HTTP server that receives webhook POSTs from external
services (GitHub, GitLab, JIRA, Stripe, etc.), validates HMAC signatures,
transforms payloads into agent prompts, and routes responses back to the
source or to another configured platform.
Configuration lives in config.yaml under platforms.webhook.extra.routes.
Each route defines:
- events: which event types to accept (header-based filtering)
- secret: HMAC secret for signature validation (REQUIRED)
- prompt: template string formatted with the webhook payload
- skills: optional list of skills to load for the agent
- deliver: where to send the response (github_comment, telegram, etc.)
- deliver_extra: additional delivery config (repo, pr_number, chat_id)
- deliver_only: if true, skip the agent — the rendered prompt IS the
message that gets delivered. Use for external push notifications
(Supabase, monitoring alerts, inter-agent pings) where zero LLM cost
and sub-second delivery matter more than agent reasoning.
Security:
- HMAC secret is required per route (validated at startup)
- Rate limiting per route (fixed-window, configurable)
- Idempotency cache prevents duplicate agent runs on webhook retries
- Body size limits checked before reading payload
- Set secret to "INSECURE_NO_AUTH" to skip validation (testing only)
"""
import asyncio
import hashlib
import hmac
import json
import logging
import re
import subprocess
import time
from typing import Any, Dict, List, Optional
try:
from aiohttp import web
AIOHTTP_AVAILABLE = True
except ImportError:
AIOHTTP_AVAILABLE = False
web = None
from gateway.config import Platform, PlatformConfig
from gateway.platforms.base import (
BasePlatformAdapter,
MessageEvent,
MessageType,
SendResult,
)
logger = logging.getLogger(__name__)
_BUILTIN_DELIVER_PLATFORMS = {
"telegram", "discord", "slack", "signal", "sms", "whatsapp",
"matrix", "mattermost", "homeassistant", "email", "dingtalk",
"feishu", "wecom", "wecom_callback", "weixin", "bluebubbles",
"qqbot", "yuanbao",
}
DEFAULT_HOST = "0.0.0.0"
DEFAULT_PORT = 8644
_INSECURE_NO_AUTH = "INSECURE_NO_AUTH"
_DYNAMIC_ROUTES_FILENAME = "webhook_subscriptions.json"
_LOOPBACK_HOSTS = frozenset({
"127.0.0.1",
"localhost",
"::1",
"ip6-localhost",
"ip6-loopback",
})
def _is_loopback_host(host: str) -> bool:
"""True when `host` binds only to the local machine.
Covers IPv4 loopback, the standard `localhost` alias, IPv6 loopback in
both bracketed and bare form, and the common Debian-style aliases. Any
falsy value (empty string, None) is conservatively treated as non-loopback
because an unset host usually means the platform-default public bind.
"""
if not host:
return False
return host.strip().lower() in _LOOPBACK_HOSTS
def check_webhook_requirements() -> bool:
"""Check if webhook adapter dependencies are available."""
return AIOHTTP_AVAILABLE
class WebhookAdapter(BasePlatformAdapter):
"""Generic webhook receiver that triggers agent runs from HTTP POSTs."""
def __init__(self, config: PlatformConfig):
super().__init__(config, Platform.WEBHOOK)
self._host: str = config.extra.get("host", DEFAULT_HOST)
self._port: int = int(config.extra.get("port", DEFAULT_PORT))
self._global_secret: str = config.extra.get("secret", "")
self._static_routes: Dict[str, dict] = config.extra.get("routes", {})
self._dynamic_routes: Dict[str, dict] = {}
self._dynamic_routes_mtime: float = 0.0
self._routes: Dict[str, dict] = dict(self._static_routes)
self._runner = None
self._delivery_info: Dict[str, dict] = {}
self._delivery_info_created: Dict[str, float] = {}
self.gateway_runner = None
self._seen_deliveries: Dict[str, float] = {}
self._idempotency_ttl: int = 3600
self._rate_counts: Dict[str, List[float]] = {}
self._rate_limit: int = int(config.extra.get("rate_limit", 30))
self._max_body_bytes: int = int(
config.extra.get("max_body_bytes", 1_048_576)
)
async def connect(self) -> bool:
self._reload_dynamic_routes()
for name, route in self._routes.items():
secret = route.get("secret", self._global_secret)
if not secret:
raise ValueError(
f"[webhook] Route '{name}' has no HMAC secret. "
f"Set 'secret' on the route or globally. "
f"For testing without auth, set secret to '{_INSECURE_NO_AUTH}'."
)
if secret == _INSECURE_NO_AUTH and not _is_loopback_host(self._host):
raise ValueError(
f"[webhook] Route '{name}' uses INSECURE_NO_AUTH secret "
f"but is bound to non-loopback host '{self._host}'. "
f"INSECURE_NO_AUTH is for local testing only. "
f"Refusing to start to prevent accidental exposure."
)
if route.get("deliver_only"):
deliver = route.get("deliver", "log")
if not deliver or deliver == "log":
raise ValueError(
f"[webhook] Route '{name}' has deliver_only=true but "
f"deliver is '{deliver}'. Direct delivery requires a "
f"real target (telegram, discord, slack, github_comment, etc.)."
)
app = web.Application()
app.router.add_get("/health", self._handle_health)
app.router.add_post("/webhooks/{route_name}", self._handle_webhook)
import socket as _socket
try:
with _socket.socket(_socket.AF_INET, _socket.SOCK_STREAM) as _s:
_s.settimeout(1)
_s.connect(('127.0.0.1', self._port))
logger.error('[webhook] Port %d already in use. Set a different port in config.yaml: platforms.webhook.port', self._port)
return False
except (ConnectionRefusedError, OSError):
pass
self._runner = web.AppRunner(app)
await self._runner.setup()
site = web.TCPSite(self._runner, self._host, self._port)
await site.start()
self._mark_connected()
route_names = ", ".join(self._routes.keys()) or "(none configured)"
logger.info(
"[webhook] Listening on %s:%d — routes: %s",
self._host,
self._port,
route_names,
)
return True
async def disconnect(self) -> None:
if self._runner:
await self._runner.cleanup()
self._runner = None
self._mark_disconnected()
logger.info("[webhook] Disconnected")
async def send(
self,
chat_id: str,
content: str,
reply_to: Optional[str] = None,
metadata: Optional[Dict[str, Any]] = None,
) -> SendResult:
"""Deliver the agent's response to the configured destination.
chat_id is ``webhook:{route}:{delivery_id}``. The delivery info
stored during webhook receipt is read with ``.get()`` (not popped)
so that interim status messages emitted before the final response
— fallback-model notifications, context-pressure warnings, etc. —
do not consume the entry and silently downgrade the final response
to the ``log`` deliver type. TTL cleanup happens on POST.
"""
delivery = self._delivery_info.get(chat_id, {})
deliver_type = delivery.get("deliver", "log")
if deliver_type == "log":
logger.info("[webhook] Response for %s: %s", chat_id, content[:200])
return SendResult(success=True)
if deliver_type == "github_comment":
return await self._deliver_github_comment(content, delivery)
_is_known_platform = deliver_type in _BUILTIN_DELIVER_PLATFORMS
if not _is_known_platform:
try:
from gateway.platform_registry import platform_registry
_is_known_platform = platform_registry.is_registered(deliver_type)
except Exception:
pass
if self.gateway_runner and _is_known_platform:
return await self._deliver_cross_platform(
deliver_type, content, delivery
)
logger.warning("[webhook] Unknown deliver type: %s", deliver_type)
return SendResult(
success=False, error=f"Unknown deliver type: {deliver_type}"
)
def _prune_delivery_info(self, now: float) -> None:
"""Drop delivery_info entries older than the idempotency TTL.
Mirrors the cleanup pattern used for ``_seen_deliveries``. Called
on each POST so the dict size is bounded by ``rate_limit * TTL``
even if many webhooks fire and never receive a final response.
"""
cutoff = now - self._idempotency_ttl
stale = [
k
for k, t in self._delivery_info_created.items()
if t < cutoff
]
for k in stale:
self._delivery_info.pop(k, None)
self._delivery_info_created.pop(k, None)
async def get_chat_info(self, chat_id: str) -> Dict[str, Any]:
return {"name": chat_id, "type": "webhook"}
async def _handle_health(self, request: "web.Request") -> "web.Response":
"""GET /health — simple health check."""
return web.json_response({"status": "ok", "platform": "webhook"})
def _reload_dynamic_routes(self) -> None:
"""Reload agent-created subscriptions from disk if the file changed."""
from hermes_constants import get_hermes_home
hermes_home = get_hermes_home()
subs_path = hermes_home / _DYNAMIC_ROUTES_FILENAME
if not subs_path.exists():
if self._dynamic_routes:
self._dynamic_routes = {}
self._routes = dict(self._static_routes)
logger.debug("[webhook] Dynamic subscriptions file removed, cleared dynamic routes")
return
try:
mtime = subs_path.stat().st_mtime
if mtime <= self._dynamic_routes_mtime:
return
data = json.loads(subs_path.read_text(encoding="utf-8"))
if not isinstance(data, dict):
return
self._dynamic_routes = {
k: v for k, v in data.items()
if k not in self._static_routes
}
self._routes = {**self._dynamic_routes, **self._static_routes}
self._dynamic_routes_mtime = mtime
logger.info(
"[webhook] Reloaded %d dynamic route(s): %s",
len(self._dynamic_routes),
", ".join(self._dynamic_routes.keys()) or "(none)",
)
except Exception as e:
logger.error("[webhook] Failed to reload dynamic routes: %s", e)
async def _handle_webhook(self, request: "web.Request") -> "web.Response":
"""POST /webhooks/{route_name} — receive and process a webhook event."""
self._reload_dynamic_routes()
route_name = request.match_info.get("route_name", "")
route_config = self._routes.get(route_name)
if not route_config:
return web.json_response(
{"error": f"Unknown route: {route_name}"}, status=404
)
content_length = request.content_length or 0
if content_length > self._max_body_bytes:
return web.json_response(
{"error": "Payload too large"}, status=413
)
try:
raw_body = await request.read()
except Exception as e:
logger.error("[webhook] Failed to read body: %s", e)
return web.json_response({"error": "Bad request"}, status=400)
secret = route_config.get("secret", self._global_secret)
if secret and secret != _INSECURE_NO_AUTH:
if not self._validate_signature(request, raw_body, secret):
logger.warning(
"[webhook] Invalid signature for route %s", route_name
)
return web.json_response(
{"error": "Invalid signature"}, status=401
)
now = time.time()
window = self._rate_counts.setdefault(route_name, [])
window[:] = [t for t in window if now - t < 60]
if len(window) >= self._rate_limit:
return web.json_response(
{"error": "Rate limit exceeded"}, status=429
)
window.append(now)
try:
payload = json.loads(raw_body)
except json.JSONDecodeError:
try:
import urllib.parse
payload = dict(
urllib.parse.parse_qsl(raw_body.decode("utf-8"))
)
except Exception:
return web.json_response(
{"error": "Cannot parse body"}, status=400
)
event_type = (
request.headers.get("X-GitHub-Event", "")
or request.headers.get("X-GitLab-Event", "")
or payload.get("event_type", "")
or "unknown"
)
allowed_events = route_config.get("events", [])
if allowed_events and event_type not in allowed_events:
logger.debug(
"[webhook] Ignoring event %s for route %s (allowed: %s)",
event_type,
route_name,
allowed_events,
)
return web.json_response(
{"status": "ignored", "event": event_type}
)
prompt_template = route_config.get("prompt", "")
prompt = self._render_prompt(
prompt_template, payload, event_type, route_name
)
skills = route_config.get("skills", [])
if skills:
try:
from agent.skill_commands import (
build_skill_invocation_message,
get_skill_commands,
)
skill_cmds = get_skill_commands()
for skill_name in skills:
cmd_key = f"/{skill_name}"
if cmd_key in skill_cmds:
skill_content = build_skill_invocation_message(
cmd_key, user_instruction=prompt
)
if skill_content:
prompt = skill_content
break
else:
logger.warning(
"[webhook] Skill '%s' not found", skill_name
)
except Exception as e:
logger.warning("[webhook] Skill loading failed: %s", e)
delivery_id = request.headers.get(
"X-GitHub-Delivery",
request.headers.get("X-Request-ID", str(int(time.time() * 1000))),
)
now = time.time()
self._seen_deliveries = {
k: v
for k, v in self._seen_deliveries.items()
if now - v < self._idempotency_ttl
}
if delivery_id in self._seen_deliveries:
logger.info(
"[webhook] Skipping duplicate delivery %s", delivery_id
)
return web.json_response(
{"status": "duplicate", "delivery_id": delivery_id},
status=200,
)
self._seen_deliveries[delivery_id] = now
if route_config.get("deliver_only"):
delivery = {
"deliver": route_config.get("deliver", "log"),
"deliver_extra": self._render_delivery_extra(
route_config.get("deliver_extra", {}), payload
),
"payload": payload,
}
logger.info(
"[webhook] direct-deliver event=%s route=%s target=%s msg_len=%d delivery=%s",
event_type,
route_name,
delivery["deliver"],
len(prompt),
delivery_id,
)
try:
result = await self._direct_deliver(prompt, delivery)
except Exception:
logger.exception(
"[webhook] direct-deliver failed route=%s delivery=%s",
route_name,
delivery_id,
)
return web.json_response(
{"status": "error", "error": "Delivery failed", "delivery_id": delivery_id},
status=502,
)
if result.success:
return web.json_response(
{
"status": "delivered",
"route": route_name,
"target": delivery["deliver"],
"delivery_id": delivery_id,
},
status=200,
)
logger.warning(
"[webhook] direct-deliver target rejected route=%s target=%s error=%s",
route_name,
delivery["deliver"],
result.error,
)
return web.json_response(
{"status": "error", "error": "Delivery failed", "delivery_id": delivery_id},
status=502,
)
session_chat_id = f"webhook:{route_name}:{delivery_id}"
deliver_config = {
"deliver": route_config.get("deliver", "log"),
"deliver_extra": self._render_delivery_extra(
route_config.get("deliver_extra", {}), payload
),
"payload": payload,
}
self._delivery_info[session_chat_id] = deliver_config
self._delivery_info_created[session_chat_id] = now
self._prune_delivery_info(now)
source = self.build_source(
chat_id=session_chat_id,
chat_name=f"webhook/{route_name}",
chat_type="webhook",
user_id=f"webhook:{route_name}",
user_name=route_name,
)
event = MessageEvent(
text=prompt,
message_type=MessageType.TEXT,
source=source,
raw_message=payload,
message_id=delivery_id,
)
logger.info(
"[webhook] %s event=%s route=%s prompt_len=%d delivery=%s",
request.method,
event_type,
route_name,
len(prompt),
delivery_id,
)
task = asyncio.create_task(self.handle_message(event))
self._background_tasks.add(task)
task.add_done_callback(self._background_tasks.discard)
return web.json_response(
{
"status": "accepted",
"route": route_name,
"event": event_type,
"delivery_id": delivery_id,
},
status=202,
)
def _validate_signature(
self, request: "web.Request", body: bytes, secret: str
) -> bool:
"""Validate webhook signature (GitHub, GitLab, generic HMAC-SHA256)."""
gh_sig = request.headers.get("X-Hub-Signature-256", "")
if gh_sig:
expected = "sha256=" + hmac.new(
secret.encode(), body, hashlib.sha256
).hexdigest()
return hmac.compare_digest(gh_sig, expected)
gl_token = request.headers.get("X-Gitlab-Token", "")
if gl_token:
return hmac.compare_digest(gl_token, secret)
generic_sig = request.headers.get("X-Webhook-Signature", "")
if generic_sig:
expected = hmac.new(
secret.encode(), body, hashlib.sha256
).hexdigest()
return hmac.compare_digest(generic_sig, expected)
logger.debug(
"[webhook] Secret configured but no signature header found"
)
return False
def _render_prompt(
self,
template: str,
payload: dict,
event_type: str,
route_name: str,
) -> str:
"""Render a prompt template with the webhook payload.
Supports dot-notation access into nested dicts:
``{pull_request.title}`` → ``payload["pull_request"]["title"]``
Special token ``{__raw__}`` dumps the entire payload as indented
JSON (truncated to 4000 chars). Useful for monitoring alerts or
any webhook where the agent needs to see the full payload.
"""
if not template:
truncated = json.dumps(payload, indent=2)[:4000]
return (
f"Webhook event '{event_type}' on route "
f"'{route_name}':\n\n```json\n{truncated}\n```"
)
def _resolve(match: re.Match) -> str:
key = match.group(1)
if key == "__raw__":
return json.dumps(payload, indent=2)[:4000]
value: Any = payload
for part in key.split("."):
if isinstance(value, dict):
value = value.get(part, f"{{{key}}}")
else:
return f"{{{key}}}"
if isinstance(value, (dict, list)):
return json.dumps(value, indent=2)[:2000]
return str(value)
return re.sub(r"\{([a-zA-Z0-9_.]+)\}", _resolve, template)
def _render_delivery_extra(
self, extra: dict, payload: dict
) -> dict:
"""Render delivery_extra template values with payload data."""
rendered: Dict[str, Any] = {}
for key, value in extra.items():
if isinstance(value, str):
rendered[key] = self._render_prompt(value, payload, "", "")
else:
rendered[key] = value
return rendered
async def _direct_deliver(
self, content: str, delivery: dict
) -> SendResult:
"""Deliver *content* directly without invoking the agent.
Used by ``deliver_only`` routes: the rendered template becomes the
literal message body, and we dispatch to the same delivery helpers
that the agent-mode ``send()`` flow uses. All target types that
work in agent mode work here — Telegram, Discord, Slack, GitHub
PR comments, etc.
"""
deliver_type = delivery.get("deliver", "log")
if deliver_type == "log":
logger.info("[webhook] direct-deliver log-only: %s", content[:200])
return SendResult(success=True)
if deliver_type == "github_comment":
return await self._deliver_github_comment(content, delivery)
return await self._deliver_cross_platform(
deliver_type, content, delivery
)
async def _deliver_github_comment(
self, content: str, delivery: dict
) -> SendResult:
"""Post agent response as a GitHub PR/issue comment via ``gh`` CLI."""
extra = delivery.get("deliver_extra", {})
repo = extra.get("repo", "")
pr_number = extra.get("pr_number", "")
if not repo or not pr_number:
logger.error(
"[webhook] github_comment delivery missing repo or pr_number"
)
return SendResult(
success=False, error="Missing repo or pr_number"
)
try:
result = subprocess.run(
[
"gh",
"pr",
"comment",
str(pr_number),
"--repo",
repo,
"--body",
content,
],
capture_output=True,
text=True,
timeout=30,
)
if result.returncode == 0:
logger.info(
"[webhook] Posted comment on %s#%s", repo, pr_number
)
return SendResult(success=True)
else:
logger.error(
"[webhook] gh pr comment failed: %s", result.stderr
)
return SendResult(success=False, error=result.stderr)
except FileNotFoundError:
logger.error(
"[webhook] 'gh' CLI not found — install GitHub CLI for "
"github_comment delivery"
)
return SendResult(
success=False, error="gh CLI not installed"
)
except Exception as e:
logger.error("[webhook] github_comment delivery error: %s", e)
return SendResult(success=False, error=str(e))
async def _deliver_cross_platform(
self, platform_name: str, content: str, delivery: dict
) -> SendResult:
"""Route response to another platform (telegram, discord, etc.)."""
if not self.gateway_runner:
return SendResult(
success=False,
error="No gateway runner for cross-platform delivery",
)
try:
target_platform = Platform(platform_name)
except ValueError:
return SendResult(
success=False, error=f"Unknown platform: {platform_name}"
)
adapter = self.gateway_runner.adapters.get(target_platform)
if not adapter:
return SendResult(
success=False,
error=f"Platform {platform_name} not connected",
)
extra = delivery.get("deliver_extra", {})
chat_id = extra.get("chat_id", "")
if not chat_id:
home = self.gateway_runner.config.get_home_channel(target_platform)
if home:
chat_id = home.chat_id
else:
return SendResult(
success=False,
error=f"No chat_id or home channel for {platform_name}",
)
metadata = None
thread_id = extra.get("message_thread_id") or extra.get("thread_id")
if thread_id:
metadata = {"thread_id": thread_id}
return await adapter.send(chat_id, content, metadata=metadata)