Webhook Source

Overview

The Webhook Source connector lets external systems deliver webhook calls directly to KurrentDB. Each incoming payload is written as an event to a KurrentDB stream, with no middleware required in between.

Prerequisites

Before using the Webhook Source connector, ensure you have:

• A KurrentDB instance with connectors enabled
• A data protection token configured in your KurrentDB instance (required to encrypt sensitive fields like the HMAC signature secret)
• A publicly reachable KurrentDB endpoint if the upstream provider sends webhooks from outside your network

::: tip See the Data Protection documentation for instructions on configuring the encryption token. :::

Quickstart

You can create the Webhook Source connector as follows. Replace {id} with your desired connector ID.

The Webhook Source requires a routingScript: a base64-encoded UTF-8 JavaScript snippet defining a route(request) function. For each inbound request, the function returns the target stream name and optionally a schema name to tag the event with.

For example, the following function:

function route(request) {
  return {
    stream: `webhook-${request.body.resource}-${request.body.action}`,
    schema: `${request.body.resource}.${request.body.action}`,
  };
}

Base64-encoded, this becomes:

ZnVuY3Rpb24gcm91dGUocmVxdWVzdCkgeyByZXR1cm4geyBzdHJlYW06IGB3ZWJob29rLSR7cmVxdWVzdC5ib2R5LnJlc291cmNlfS0ke3JlcXVlc3QuYm9keS5hY3Rpb259YCwgc2NoZW1hOiBgJHtyZXF1ZXN0LmJvZHkucmVzb3VyY2V9LiR7cmVxdWVzdC5ib2R5LmFjdGlvbn1gIH07IH0=

Create the connector with:

POST /connectors/{id}
Host: localhost:2113
Content-Type: application/json

{
  "settings": {
    "instanceTypeName": "webhook-source",
    "routingScript": "ZnVuY3Rpb24gcm91dGUocmVxdWVzdCkgeyByZXR1cm4geyBzdHJlYW06IGB3ZWJob29rLSR7cmVxdWVzdC5ib2R5LnJlc291cmNlfS0ke3JlcXVlc3QuYm9keS5hY3Rpb259YCwgc2NoZW1hOiBgJHtyZXF1ZXN0LmJvZHkucmVzb3VyY2V9LiR7cmVxdWVzdC5ib2R5LmFjdGlvbn1gIH07IH0="
  }
}

After creating and starting the connector, send JSON payloads to the webhook endpoint:

POST /webhook/{id}
Host: localhost:2113
Content-Type: application/json

{
  "resource": "order",
  "action": "created",
  "data": { "orderId": "abc-123" }
}

The example above writes the payload to stream webhook-order-created with event type order.created. By default, the connector returns 202 Accepted as soon as it accepts the payload for processing. You can find a list of available management API endpoints in the API Reference.

Settings

Adjust these settings to control how the Webhook Source connector writes inbound requests to KurrentDB.

::: tip The Webhook Source inherits common settings shared by all source connectors, documented on the Source Options page. :::

Description: Base64-encoded UTF-8 JavaScript that defines a route(request) function. The function returns the target stream name and an optional schema name for each inbound request. See Routing Script. | | waitForWrite | Description: When enabled, the HTTP request waits for the event to be durably written before returning a response. See Write Confirmation.

Default: "false" | | confirmationTimeout | Description: How long the request waits for a durable-write confirmation when waitForWrite is enabled. Exceeding this returns 504 Gateway Timeout.

Default: "00:00:30" (30 seconds) | | signature:scheme | Description: Pre-configured provider scheme for HMAC signature validation. Required when the signature block is present; you must pick a provider explicitly. Each scheme fully defines the header name, encoding, payload shape, and replay-protection behavior expected by that provider. See Signature Validation.

Accepted Values: "GitHub", "Shopify", "Slack", "Stripe"

Default: not set (must be specified) | | signature:secret | Description: Shared HMAC secret, interpreted as UTF-8. When the signature block is present, this must be a non-empty string. When the signature block is omitted entirely, signature validation is disabled.

Default: not set (validation disabled) | | signature:timestampTolerance | Description: Maximum allowed clock skew when the chosen scheme requires timestamp validation (Slack, Stripe). Ignored for schemes that do not include a timestamp.

Default: "00:05:00" (5 minutes) | | allowedHeaders | Description: Allowlist of inbound HTTP header names (case-insensitive) persisted on the written event. Each allowed header becomes its own metadata entry on the record, keyed by its lowercased name (e.g. content-type). Anything not on this list is never stored. Webhook providers routinely send headers that carry credentials (Authorization, Cookie, API keys), so only add headers you have verified do not contain secrets.

Default: ["Content-Type", "User-Agent", "X-Request-Id"] |

Ingest Endpoint

POST /webhook/{connectorId}

The Webhook Source connector accepts POST requests only. Each request must use a JSON content type such as application/json (including application/json; charset=utf-8) and contain a non-empty UTF-8 JSON payload. The JSON payload becomes the event data written to KurrentDB.

Routing Script

The routing script is a base64-encoded UTF-8 JavaScript snippet that must define a function named route. The function is invoked once per inbound request to compute the target stream and (optionally) the schema name.

Request shape

The function receives a single request argument with the following fields:

Header keys are always lowercased before they are passed to the script.

Return value

The function must return an object containing a stream property, which is the target stream name to write the event to. The stream must be a non-empty string and must not start with $. An optional schema property tags the event with a custom event type; when omitted, events are written with the default event type WebhookReceived.

Routing outcomes

The function's return value determines what happens to the request. To route a request, return an object with a non-empty stream (and optionally a schema); the request is written to that stream. To skip a request, return null, undefined, or an object with an empty stream, and the connector responds with 400 Bad Request without writing an event. If the function throws, runs too long, returns something other than an object, or returns an invalid stream or schema, the connector responds with 500 Internal Server Error.

Example

Route Stripe events to per-account streams and tag each event with its Stripe event type:

function route(request) {
  return {
    stream: `stripe-${request.body.account}`,
    schema: `stripe.${request.body.type}`,
  };
}

Write Confirmation

By default, the connector returns 202 Accepted as soon as the payload enters the in-memory pipeline. A 202 confirms acceptance for processing, not durable persistence. Enable waitForWrite to receive 201 Created only once the event has been durably written.

Signature Validation

When a signature block is configured, the connector validates the HMAC-SHA256 signature of every incoming request using the rules of the chosen scheme. Requests with missing, malformed, or invalid signatures are rejected with 401 Unauthorized. For schemes that include a timestamp, requests outside the configured tolerance window are also rejected with 401 Unauthorized.

Each scheme fully defines the header name, encoding, signed-payload shape, and replay-protection behavior expected by that provider, so you only need to pick the scheme and supply the secret.

GitHub

POST /connectors/{id}
Host: localhost:2113
Content-Type: application/json

{
  "settings": {
    "instanceTypeName": "webhook-source",
    "routingScript": "<base64-encoded route() function>",
    "signature": {
      "scheme": "GitHub",
      "secret": "your-github-webhook-secret"
    }
  }
}

Shopify

POST /connectors/{id}
Host: localhost:2113
Content-Type: application/json

{
  "settings": {
    "instanceTypeName": "webhook-source",
    "routingScript": "<base64-encoded route() function>",
    "signature": {
      "scheme": "Shopify",
      "secret": "your-shopify-secret"
    }
  }
}

Slack

Slack signs v0:{timestamp}:{body} and requires the timestamp header to be within the tolerance window:

POST /connectors/{id}
Host: localhost:2113
Content-Type: application/json

{
  "settings": {
    "instanceTypeName": "webhook-source",
    "routingScript": "<base64-encoded route() function>",
    "signature": {
      "scheme": "Slack",
      "secret": "your-slack-signing-secret",
      "timestampTolerance": "00:05:00"
    }
  }
}

Stripe

Stripe sends a single Stripe-Signature header containing comma-separated pairs (t=…,v1=…). The signed payload is {timestamp}.{body}:

POST /connectors/{id}
Host: localhost:2113
Content-Type: application/json

{
  "settings": {
    "instanceTypeName": "webhook-source",
    "routingScript": "<base64-encoded route() function>",
    "signature": {
      "scheme": "Stripe",
      "secret": "your-stripe-webhook-secret",
      "timestampTolerance": "00:05:00"
    }
  }
}