Salesforce Webhooks (Outbound Messages) Skill

Salesforce has no classic HMAC-signed webhook. The closest native push is the Outbound Message, configured on a Flow or Workflow Rule, which POSTs a SOAP/XML envelope to your HTTPS endpoint when a record changes.

There is no signature header. You authenticate the message by:

1. Validating <OrganizationId> in the SOAP body against your known 18-char Salesforce org id.
2. Enforcing HTTPS and restricting inbound traffic to Salesforce IP ranges.
3. Optionally mutual TLS (Salesforce can present a client certificate).

Your endpoint must return a SOAP <Ack>true</Ack> envelope with HTTP 200, or Salesforce retries the message for up to 24 hours.

When to Use This Skill

• How do I receive Salesforce webhooks / Outbound Messages?
• How do I parse the Salesforce Outbound Message SOAP/XML body?
• How do I validate the OrganizationId on a Salesforce Outbound Message?
• What Ack response does a Salesforce Outbound Message listener return?
• How do I handle Account, Opportunity, Contact, Lead, or Case record changes?
• Should I use Outbound Messages, Platform Events, or Change Data Capture?

Verification (core)

Outbound Messages are unsigned. "Verification" = parse the SOAP body, match <OrganizationId> (timing-safe) against your org id, then return the Ack. Use the raw request body — Salesforce sends Content-Type: text/xml, so parse XML, not JSON.

const { XMLParser } = require('fast-xml-parser');
const crypto = require('crypto');

// removeNSPrefix strips soapenv:/sf: prefixes so we can read plain element names.
const parser = new XMLParser({ ignoreAttributes: false, removeNSPrefix: true });

// rawXml = raw HTTP body string; expectedOrgId = your 18-char Salesforce org id.
function verifyOutboundMessage(rawXml, expectedOrgId) {
  const msg = parser.parse(rawXml)?.Envelope?.Body?.notifications;
  const orgId = String(msg?.OrganizationId ?? '');
  const a = Buffer.from(orgId), b = Buffer.from(expectedOrgId);
  if (a.length !== b.length || !crypto.timingSafeEqual(a, b)) {
    throw new Error('OrganizationId mismatch — reject with 401');
  }
  return msg; // dispatch [].concat(msg.Notification) then return the Ack envelope below
}

The Ack envelope every successful listener must return (Content-Type: text/xml, HTTP 200):

<?xml version="1.0" encoding="UTF-8"?>
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/">
  <soapenv:Body>
    <notificationsResponse xmlns="http://soap.sforce.com/2005/09/outbound">
      <Ack>true</Ack>
    </notificationsResponse>
  </soapenv:Body>
</soapenv:Envelope>

For complete handlers with SOAP parsing, event dispatch, the Ack response, and tests, see:

• examples/express/
• examples/nextjs/
• examples/fastapi/

Common Event Types

Outbound Messages don't carry an event-name string. The "event" is the sObject type the Flow/Workflow Rule is built on, plus the create/update action. Each <Notification> contains one <sObject> whose xsi:type attribute is the type:

A single message can include up to 100 <Notification> elements. Messages may arrive out of order and more than once — handle idempotently on the <Notification> <Id> or the sObject <sf:Id>.

Full reference: Outbound Messaging

Streaming Alternative

For high-volume, real-time, or richer event streams, use Platform Events or Change Data Capture (CDC) consumed over the Pub/Sub API (or the legacy CometD Streaming API) rather than Outbound Messages. See references/overview.md.

Environment Variables

SALESFORCE_ORG_ID=00Dxx0000000000EAA   # Your 18-char org id (Setup → Company Information)

Local Development

# Start tunnel (no account needed) — point your Outbound Message endpoint at the Hookdeck URL
npx hookdeck-cli listen 3000 salesforce --path /webhooks/salesforce

Reference Materials

• references/overview.md - Outbound Messages, Platform Events, CDC, common sObjects
• references/setup.md - Configure the Outbound Message in Salesforce Setup
• references/verification.md - OrganizationId validation, IP allowlist, mTLS, gotchas