Block Users

Block and unblock users in chat apps with the CometChat JavaScript SDK.

AI Integration Quick Reference

Field	Value
Package	@cometchat/chat-sdk-javascript
Import	import { CometChat } from "@cometchat/chat-sdk-javascript";
Key methods	CometChat.blockUsers(usersList) · CometChat.unblockUsers(usersList) · blockedUsersRequest.fetchNext() (build via BlockedUsersRequestBuilder)
Request builder	CometChat.BlockedUsersRequestBuilder — configure with .setLimit() · .setSearchKeyword() · .setDirection(); then .build() → .fetchNext()
Key classes	CometChat.User (access via getBlockedByMe(), getHasBlockedMe()); direction via CometChat.BlockedUsersRequest.directions.BLOCKED_BY_ME / .HAS_BLOCKED_ME / .BOTH
Primary output	blockUsers() / unblockUsers() resolve to a { uid: "success" | "fail" } object (each UID processed independently); fetchNext() resolves to Promise<CometChat.User[]>; all reject with CometChat.CometChatException
Prerequisites	SDK initialized via CometChat.init() and a logged-in user via CometChat.login()
Constraints	setDirection() default is BOTH; blockUsers() / unblockUsers() take an array of UIDs
Related	Retrieve Users · User Presence · User Management · Flag a Message
Full reference	User

​

Block Users

Block users to prevent all communication with them. Use blockUsers() with an array of UIDs.

TypeScript

const usersList: String[] = ["UID1", "UID2", "UID3"];

CometChat.blockUsers(usersList).then(
(list: Object) => {
console.log("users list blocked", { list });
}, (error: CometChat.CometChatException) => {
console.log("Blocking user fails with error", error);
}
);

JavaScript

const usersList = ["UID1", "UID2", "UID3"];

CometChat.blockUsers(usersList).then(
list => {
  console.log("users list blocked", { list });
}, error => {
  console.log("Blocking user fails with error", error);
}
);

Alternatively, you can use the async/await syntax:

const usersList = ["UID1", "UID2", "UID3"];

try {
  const list = await CometChat.blockUsers(usersList);
  console.log("users list blocked", { list });
} catch (error) {
  console.log("Blocking user fails with error", error);
}

Returns an object with UIDs as keys and "success" or "fail" as values. Each User in the request is processed independently.

​

Unblock Users

Unblock previously blocked users using unblockUsers() with an array of UIDs.

TypeScript

const usersList: String[] = ["UID1", "UID2", "UID3"];

CometChat.unblockUsers(usersList).then(
(list: Object) => {
console.log("users list blocked", { list });
}, (error: CometChat.CometChatException) => {
console.log("Blocking user fails with error", error);
}
);

JavaScript

const usersList = ["UID1", "UID2", "UID3"];

CometChat.unblockUsers(usersList).then(
list => {
  console.log("users list unblocked", { list });
}, error => {
  console.log("unblocking user fails with error", error);
}
);

Alternatively, you can use the async/await syntax:

const usersList = ["UID1", "UID2", "UID3"];

try {
  const list = await CometChat.unblockUsers(usersList);
  console.log("users list unblocked", { list });
} catch (error) {
  console.log("unblocking user fails with error", error);
}

Returns an object with UIDs as keys and "success" or "fail" as values. Each User in the request is processed independently.

​

Get List of Blocked Users

Use BlockedUsersRequestBuilder to fetch blocked users with filtering and pagination.

​

Set Limit

Sets the number of blocked users to fetch per request.

TypeScript

let limit: number = 30;
let blockedUsersRequest: CometChat.BlockedUsersRequest = new CometChat.BlockedUsersRequestBuilder()
  .setLimit(limit)
  .build();

JavaScript

let limit = 30;
let blockedUsersRequest = new CometChat.BlockedUsersRequestBuilder()
                  				.setLimit(limit)
                  				.build();

​

Set Search Keyword

With offline support on, this filter is answered by the server only; onCachedUsers does not fire.

Filters blocked users by a search string.

TypeScript

let limit: number = 30;
let searchKeyword: string = "super";
let blockedUsersRequest: CometChat.BlockedUsersRequest = new CometChat.BlockedUsersRequestBuilder()
  .setLimit(limit)
  .setSearchKeyword(searchKeyword)
  .build();

JavaScript

let limit = 30;
let searchKeyword = "super";
let blockedUsersRequest = new CometChat.BlockedUsersRequestBuilder()
                  				.setLimit(limit)
                  				.setSearchKeyword(searchKeyword)
                  				.build();

​

Set Direction

Filters by block direction:

• BLOCKED_BY_ME — Users blocked by the logged-in user
• HAS_BLOCKED_ME — Users who have blocked the logged-in user
• BOTH — Both directions (default)

TypeScript

let limit: number = 30;
let blockedUsersRequest: CometChat.BlockedUsersRequest = new CometChat.BlockedUsersRequestBuilder()
  .setLimit(limit)
  .setDirection(CometChat.BlockedUsersRequest.directions.BLOCKED_BY_ME)
  .build();

JavaScript

let limit = 30; let blockedUsersRequest = new

CometChat.BlockedUsersRequestBuilder() .setLimit(limit)
.setDirection(CometChat.BlockedUsersRequest.directions.BLOCKED_BY_ME)
.build(); ```
</Tab>

</Tabs>

Finally, once all the parameters are set to the builder class, you need to call the build() method to get the object of the `BlockedUsersRequest` class.

Once you have the object of the `BlockedUsersRequest` class, you need to call the `fetchNext()` method. Calling this method will return a list of [`User`](/sdk/reference/entities#user) objects containing n number of blocked users where N is the limit set in the builder class.

<Tabs>
<Tab title="TypeScript">
```typescript
let limit = 30;
let blockedUsersRequest = new CometChat.BlockedUsersRequestBuilder()
.setLimit(limit)
.setDirection(CometChat.BlockedUsersRequest.directions.BLOCKED_BY_ME)
.build();

JavaScript

let limit = 30; let blockedUsersRequest = new

CometChat.BlockedUsersRequestBuilder() .setLimit(limit)
.setDirection(CometChat.BlockedUsersRequest.directions.BLOCKED_BY_ME)
.build(); ```
</Tab>

</Tabs>

After configuring the builder, call `build()` to get the `BlockedUsersRequest` object, then call `fetchNext()` to retrieve blocked users.

<Tabs>
<Tab title="TypeScript">
```typescript
let limit: number = 30;
let blockedUsersRequest: CometChat.BlockedUsersRequest = new CometChat.BlockedUsersRequestBuilder()
.setLimit(limit)
.build();

blockedUsersRequest.fetchNext().then(
(userList: CometChat.User[]) => {
console.log("Blocked user list received:", userList);
}, (error: CometChat.CometChatException) => {
console.log("Blocked user list fetching failed with error:", error);
}
);

JavaScript

const limit = 30;
const blockedUsersRequest = new CometChat.BlockedUsersRequestBuilder()
                  				.setLimit(limit)
                  				.build();
blockedUsersRequest.fetchNext().then(
userList => {
  console.log("Blocked user list received:", userList);
}, error => {
  console.log("Blocked user list fetching failed with error:", error);
}
);

The fetchNext() method returns an array of User objects representing blocked users.

Relevant fields to access on returned users:

Field	Getter	Return Type	Description
blockedByMe	getBlockedByMe()	boolean	Whether the logged-in user has blocked this user
hasBlockedMe	getHasBlockedMe()	boolean	Whether this user has blocked the logged-in user

​

Offline Behaviour

With offline support enabled, BlockedUsersRequest.fetchNext() accepts a UserFetchListener and first delivers onCachedUsers from the SDK’s own blocked-users list, which it refreshes on login and on reconnect and updates when you call blockUsers() or unblockUsers(). Then onServerUsers delivers the live page to reconcile by uid; the server page is not saved to the device. The cached page is empty when no users are blocked. When setSearchKeyword() is set, the cached phase is skipped, so onCachedUsers does not fire. Offline, the read ends with onError with code FAILED_TO_FETCH after the cached page, or with onError alone when the cached phase is skipped. See Show Cached Data.

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​

Next Steps

Retrieve Users

Fetch and filter user lists

User Presence

Track online/offline status of users

User Management

Create, update, and delete users

Flag Message

Report inappropriate messages from users