Webhooks

Source of truth: src/lib/webhookDispatcher.ts, src/lib/db/webhooks.ts, src/app/api/webhooks/ Last updated: 2026-06-28 — v3.8.40

OmniRoute can fire HTTP webhooks on platform events. Use them to integrate with Slack, PagerDuty, Datadog, internal alerting services, or any HTTP receiver.

The dispatcher signs each delivery with HMAC-SHA256, retries on transient failures, tracks delivery health per webhook, and auto-disables endpoints that keep failing.

Supported Events

The WebhookEvent type (src/lib/webhooks/eventDescriptions.ts, consumed by src/lib/webhookDispatcher.ts) currently models exactly four events:

Event	Fires when
request.completed	A proxied request completes successfully
request.failed	A proxied request fails after all retries/fallback
quota.exceeded	An API key crosses a budget/quota threshold
test.ping	Synthetic event used by the test endpoint

Subscriptions accept the literal "*" to receive every event. Unknown event names in events are ignored at dispatch time.

Note: the dispatcher API is wired, but production call sites for some of the non-test.ping events are still landing. Check grep dispatchEvent to see which paths currently invoke the dispatcher in your release.

Architecture

Caller (handler, service, monitor)
  dispatchEvent(event, data)            [src/lib/webhookDispatcher.ts]
    -> getEnabledWebhooks()             [src/lib/db/webhooks.ts]
    -> filter by webhook.events
    -> for each match (in parallel):
       deliverWebhook(url, payload, secret)
         build payload { event, timestamp, data }
         sign body with HMAC-SHA256 (if secret present)
         POST with 10s timeout
         retry up to 3 times on 5xx / network error
       recordWebhookDelivery(id, status, success)
    -> disableWebhooksWithHighFailures(10)

Dispatch is fire-and-forget for the caller: Promise.allSettled swallows per-webhook errors so one bad receiver cannot block the others.

HMAC Signing

When a webhook has a secret, OmniRoute signs the JSON body and sends:

Content-Type: application/json
User-Agent: OmniRoute-Webhook/1.0
X-Webhook-Event: <event>
X-Webhook-Timestamp: <ISO-8601>
X-Webhook-Signature: sha256=<hex HMAC-SHA256(secret, body)>

Header names use the X-Webhook-* prefix (not X-OmniRoute-*). The signature value is sha256=<hex> — verify the full prefix.

If createWebhook is called without a secret, the DB module generates one (whsec_<48 hex>) so all webhooks are signed by default.

Verifying on the receiver

import { createHmac, timingSafeEqual } from "node:crypto";

function verify(rawBody: string, signature: string, secret: string) {
  const expected = "sha256=" + createHmac("sha256", secret).update(rawBody).digest("hex");
  const a = Buffer.from(expected);
  const b = Buffer.from(signature);
  return a.length === b.length && timingSafeEqual(a, b);
}

Always verify against the raw request body, before any JSON parsing.

Retry & Failure Policy

deliverWebhook(url, payload, secret, maxRetries = 3):

• 10 second timeout per attempt (AbortController).
• HTTP 2xx counts as success.
• HTTP 3xx/4xx counts as a non-retryable final status — recorded as delivered with success = res.ok.
• HTTP 5xx and network errors are retried with exponential backoff: 2^attempt * 1000 ms (1s, 2s, 4s).
• After maxRetries, the delivery is recorded as failed.
• Each delivery updates last_triggered_at, last_status, and either resets or increments failure_count.
• The dispatcher calls disableWebhooksWithHighFailures(10) after each fan-out, so any webhook with failure_count >= 10 is automatically disabled.

Database

Table webhooks (migration 011_webhooks.sql):

Column	Type	Notes
id	TEXT PK	UUID
url	TEXT	Destination URL
events	TEXT	JSON array; default ["*"]
secret	TEXT	HMAC secret (auto-generated if not given)
enabled	INT	0/1; defaults to 1
description	TEXT	Optional human label
created_at	TEXT	datetime('now')
last_triggered_at	TEXT	Updated on every delivery attempt
last_status	INT	HTTP status of the last attempt (0 = network)
failure_count	INT	Resets to 0 on success, +1 on failure

Delivery history is persisted in the dedicated webhook_deliveries table (migration 069_webhook_deliveries.sql, written via src/lib/db/webhookDeliveries.ts::insertDelivery on every attempt), in addition to the aggregate counters on the webhooks row. Kind metadata (Slack / Discord / Telegram / custom payload transformers) was added by 070_webhooks_kind_metadata.sql.

REST API

All endpoints require management auth (requireManagementAuth).

Endpoint	Method	Description
/api/webhooks	GET	List webhooks (secrets masked)
/api/webhooks	POST	Create webhook
/api/webhooks/[id]	GET	Webhook detail (full secret)
/api/webhooks/[id]	PUT	Update fields
/api/webhooks/[id]	DELETE	Remove
/api/webhooks/[id]/test	POST	Fire a test.ping (no retries)
/api/webhooks/[id]/deliveries	GET	Recent delivery attempts for one webhook
/api/webhooks/validate-url	POST	Pre-flight URL validation (SSRF guard)

GET /api/webhooks masks the secret to <first 10 chars>... to avoid leaking on listing pages. Use the [id] GET when you actually need the secret.

Create webhook

curl -X POST http://localhost:20128/api/webhooks \
  -H "Cookie: auth_token=..." \
  -H "Content-Type: application/json" \
  -d '{
    "url": "https://hooks.slack.com/services/...",
    "secret": "whsec_my_shared_secret",
    "events": ["quota.exceeded", "request.failed"],
    "description": "Slack alerts"
  }'

If secret is omitted, the server generates a whsec_<hex> secret and returns it in the response.

Test webhook

curl -X POST http://localhost:20128/api/webhooks/<id>/test \
  -H "Cookie: auth_token=..."

Returns { delivered, status, error }. No retries are attempted — useful for quickly validating that the receiver accepts the payload and signature.

Dashboard

The dashboard page at /dashboard/webhooks (see src/app/(dashboard)/dashboard/webhooks/page.tsx) provides:

• Create/edit webhooks with an event picker
• Status indicator (active / inactive / errored) based on enabled, failure_count, and last_status
• One-click test delivery
• Manual enable/disable toggle

Payload Examples

request.completed

{
  "event": "request.completed",
  "timestamp": "2026-05-13T20:30:00.123Z",
  "data": {
    "trace_id": "...",
    "api_key_id": "...",
    "provider": "openai",
    "model": "gpt-5",
    "status": 200,
    "tokens_in": 142,
    "tokens_out": 350,
    "cost_usd": 0.0042
  }
}

test.ping

{
  "event": "test.ping",
  "timestamp": "2026-05-13T20:32:00.000Z",
  "data": {
    "message": "Test webhook delivery from OmniRoute",
    "webhookId": "<uuid>"
  }
}

Field shapes for non-test.ping events are defined by the call sites that emit them; treat the data object as forward-compatible (add fields, don’t depend on absence).

Best Practices

• Verify the signature on every delivery against the raw body — prevents spoofed POSTs from anyone who guesses your webhook URL.
• Respond 2xx within ~5 seconds — the dispatcher times out at 10 s. Slow receivers will eat retries and inflate failure_count.
• Make handlers idempotent — retries and at-least-once delivery semantics mean duplicates are possible.
• Subscribe minimally — list only events you actually consume; "*" will add cost on receivers you do not control.
• Watch failure_count — endpoints are auto-disabled at 10 consecutive failures; reset by calling PUT /api/webhooks/[id] with enabled: true after fixing the receiver.
• Rotate secrets periodically — PUT a new secret, deploy the new value to the receiver, and confirm via the test endpoint.

See Also

• API_REFERENCE.md — full management API surface
• RESILIENCE_GUIDE.md — circuit breaker / cooldown semantics behind provider failures surfaced via request.failed
• Source: src/lib/webhookDispatcher.ts, src/lib/db/webhooks.ts

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