Initialization & Users

The code below creates a chat client instance for interacting with Stream APIs. A singleton client instance means the Chat client is created once and reused throughout your app, ensuring consistent state, avoiding duplicate connections, and simplifying resource management.

// client-side you initialize the Chat client with your API key
final client = StreamChatClient(
 "{{ api_key }}",
 logLevel: Level.INFO,
 connectTimeout: Duration(milliseconds: 6000),
 receiveTimeout: Duration(milliseconds: 6000),
);

Connecting Users

Once the client is initialized, your app authenticates the user and establishes a Websocket connection by calling connectUser. This function uses your token provider function to request a token from your server.

The connectUser function acts as an upsert for the user object and is a primary method for creating users client-side.

Before attempting subsequent API requests to Stream, it is important that the connectUser function fully resolves.

final user = User(id: "john", extraData: {
 "name": "John Doe",
 "image": "https://i.imgur.com/fR9Jz14.png",
});

await client.connectUser(user, "{{ chat_user_token }}");

Connect User Parameters

nametypedescriptiondefaultoptional
userobjectThe user object. Must have an id field. User Ids can only contain characters a-z, 0-9, and special characters @ _ and - It can have as many custom fields as you want, as long as the total size of the object is less than 5KB
userTokenstring/functionThe Token Provider function or authentication token. See Tokens & Authentication for detailsdefault

Disconnecting Users

The client-side SDKs handle WebSocket disconnection logic, but if a manual disconnect is required in your application, there are the following options:

await client.disconnectUser();

XHR Fallback

Most browsers support WebSocket connections as an efficient mode of real-time data transfer. However, sometimes the connection cannot be established due to network or a corporate firewall. In such cases, the client will establish or switch to XHR fallback mechanisms and gently poll our service to keep the client up-to-date.

The fallback mechanism can be enabled with the flag enableWSFallback

const chatClient = StreamChat.getInstance(‘apiKey’, { enableWSFallBack: true });

Privacy Settings

Additionally, when connecting the user, you can include the privacy_settings as part of the user object.

final user = OwnUser(
  id: "john",
  extraData: {
    "name": "John Doe",
    "image": "https://i.imgur.com/fR9Jz14.png",
  },
  privacySettings: PrivacySettings(
    typingIndicators: TypingIndicators(
      enabled: false,
    ),
    readReceipts: ReadReceipts(
      enabled: false,
    ),
  ),
);

await client.connectUser(user, "{{ chat_user_token }}");
nametypedescriptiondefaultoptional
typing_indicatorsobjectif enabled is set to false, then typing.start and typing.stop events will be ignored for this user and these events will not be sent to othersenabled: true
read_receiptsobjectIf enabled is set to false, then the read_state of this user will not be exposed to others. Additionally, read_state related events will not be delivered to others when this user reads messages.enabled: true