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Chat Functions

ChatKitty provides Chat Functions, serverless cloud functions that allow you to define custom logic for complex tasks like user authentication, and respond to chat events that happen within your application.

Chat Functions let you write arbitrary code that runs any time a relevant event or action happens inside your app. You can send push notifications, create emails or make HTTP calls to your backend, as well as use a pre-initialized server-side ChatKitty SDK to make changes to your application in response to user actions.

You can create, edit, test, and deploy chat functions from the ChatKitty dashboard.


To define ChatKitty Chat Functions, you'll need to be familiar with basic TypeScript or JavaScript.

Blocking vs non-blocking chat functions

A chat function can be blocking or non-blocking, depending on its trigger type.

Blocking chat functions run synchronously before an action related to your ChatKitty application and can be used to modify the behavior of your application.

Non-blocking chat functions run after an action related to your ChatKitty application happens and can be used to include additional functionality or integrate an external system with your ChatKitty application.

Blocking chat functions

User attempted start session

This function is triggered when a user attempts to connect to ChatKitty, starting a new user chat session. Inside this function you can define custom logic to authenticate the user, check their credentials, create the user's ChatKitty profile or hook into your own backend. This function get passed in the username of the user attempting to start a session, and any authentication parameters you include client-side using the authParams property.

Non-blocking chat functions

User received notification

This function is triggered after a chat event a user should be notified about, (like a message sent in a channel they belong into, or a reaction on their message) occurs. Inside this function you can define custom logic to notify the user of the event that occurred (for example using an email sender or push notification service). This function get passed in the user that received the notification, the notification received, and a boolean true if the user is currently online.

Defining a chat function

You can define chat functions from the "Functions" page of your ChatKitty application dashboard.

User Received Notification Chat Function

Every chat function has two input parameters, an event that triggered the chat function call with event data, and a context containing chat function and application-specific data and helper objects, including pre-initialized ChatKitty Platform API clients.

Only events of a specific corresponding type can trigger a chat function. These types are referenced as trigger types. For example, whenever a user receives a ChatKitty notification, a UserReceivedNotificationEvent event is created. If you've defined a chat function with its corresponding trigger type, "User Received Notification", then the chat functions get called with the created UserReceivedNotificationEvent.

Chat functions automatically run when an event of their trigger type occurs.


After saving a new chat function version using the code editor, your chat function gets deployed.

Your Chat Runtime

Your chat runtime provides the environment your chat functions run. This includes a pre-initialized ChatKitty Server-side SDK, dependency NPM modules, environment variables and custom code that executes before each function.

You can use any NPM package inside your Chat Functions as a Chat Runtime dependency.

Adding a chat runtime dependency

To add a chat runtime dependency, from your ChatKitty application dashboard, go to the "Functions" page:

From the ChatKitty dashboard side menu, select "Functions"

Then from the "Functions" page, go to the "Runtime" tab:

From the "Runtime" tab you can add a new dependency using the name of the NPM package you want to install and the version of the package you want to install.

For example, installing version 7.24.0 of the Firebase NPM package looks like this:

Installing a Chat Runtime NPM dependency

Using the package name firebase and the package version 7.24.0.

An equivalent npm command for this would be npm install firebase@7.24.0.

Aftering installing a chat runtime dependency, you can import it into your chat functions and initialization script using the CommonJS require function.


Remember to click the "Save" icon to confirm your chat runtime dependencies changes.

Adding a chat runtime initialization script

If you need to run initialization logic before running your chat function, you can add arbitrary code using a chat runtime initialization script.

To add an initialization script, from the "Runtime" tab of the "Functions" page, click the dropdown and select "Initialization Script".

Chat Runtime Initialization Script


Remember to click the "Save" icon to confirm your chat runtime initialization script changes.