Webhooks Overview

By using webhooks, you can tightly integrate your server application with Stream Chat. The platform supports three kinds of webhooks: Push, Before-Message-Send, and Custom Commands. All of them follow the common set of rules:

• Webhook should be reachable from the public internet. Tunneling services like Ngrok are supported

• Webhook should accept HTTP POST requests with JSON payload

• Webhook should respond with response codes from 200 to 299

• Webhook should respond as fast as possible. The exact time given for the response varies between webhook types

• Webhook should be ready to accept the same call multiple times: in case of network or remote server failure Stream Chat could retry the request (behavior varies between webhook types)

All webhook requests contain these headers:

We highly recommend following common security guidelines to make your webhook integration safe and fast:

• Use HTTPS with a certificate from a trusted authority (eg. Let's Encrypt)

• Verify the "X-Signature" header

• Support HTTP Keep-Alive

• Be highly available

• Offload the processing of the message if possible (read, store, and forget)

Stream Chat supports several webhook types:

All HTTP requests can be verified as coming from Stream (and not tampered by a 3rd party) by analyzing the signature attached to the request. Every request includes an HTTP header called "X-Signature" containing a cryptographic signature of the message. Your webhook endpoint can validate that payload and signature match:

You can configure your webhook endpoints in the Stream Chat Dashboard or by using server-side SDK client:

Also, webhooks could be configured using our CLI client:

Some webhooks contain a field request_info, which holds information about the client that issued the request. This info is intended as an additional signal that you can use for moderation, fraud detection, or other similar purposes.

When configuring the SDK, you may also set an additional x-stream-ext header to be sent with each request. The value of this header is passed along as an ext field in the request_info. You can use this to pass along information that may be useful, such as device information. Refer to the SDK-specific docs on how to set this header.

For example, in Javascript, you can set the value like this:

The format of the ext header is up to you and you may leave it blank if you don't need it. The value is passed as-is, so you can use a simple value, comma-separated key-values, or more structured data, such as JSON. Binary data must be encoded as a string, for example using base64 or hex encoding.

If necessary, you can only expose your webhook service to Stream. This is possible by configuring your network (eg. iptables rules) to drop all incoming traffic that is not coming from our API infrastructure.

Below you can find the complete list of egress IP addresses that our webhook infrastructure uses. Such list is static and is not changing over time.