Auxiliary

Class reference for CometChat SDK auxiliary objects, including receipts, reactions, typing indicators, transient messages, attachments, and exceptions.

This page documents the auxiliary classes used across all CometChat SDKs. These objects are returned by listener callbacks and specific SDK methods.

All properties are accessed via getter methods.

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MessageReceipt

MessageReceipt represents a delivery or read receipt for a message. It is received via the onMessagesDelivered and onMessagesRead listener callbacks.

Properties

Property	Getter	Return Type	Description
messageId	getMessageId()	string	ID of the message this receipt is for
sender	getSender()	User	The user who triggered the receipt
receiver	getReceiver()	string	UID or GUID of the receiver
receiverType	getReceiverType()	string	Receiver type ("user" or "group")
receiptType	getReceiptType()	string	Type of receipt ("read", "delivery", "readByAll", or "deliveredToAll")
timestamp	getTimestamp()	string	Timestamp of the receipt
readAt	getReadAt()	number	Timestamp when the message was read (epoch seconds)
deliveredAt	getDeliveredAt()	number	Timestamp when the message was delivered (epoch seconds)

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Reaction

Reaction represents an individual user’s reaction on a message. It is returned by fetchNext() and fetchPrevious() on a ReactionsRequest object, and is also available within a ReactionEvent.

Properties

Property	Getter	Return Type	Description
id	getReactionId()	string	Unique identifier for this reaction
messageId	getMessageId()	string	ID of the message this reaction belongs to
reaction	getReaction()	string	The reaction emoji (e.g., "😀", "👍")
uid	getUid()	string	UID of the user who reacted
reactedAt	getReactedAt()	number	Timestamp when the reaction was added (epoch seconds)
reactedBy	getReactedBy()	User	The user who added this reaction

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ReactionCount

ReactionCount represents the count of a specific reaction on a message. It is available via getReactions() on a BaseMessage object.

Properties

Property	Getter	Return Type	Description
reaction	getReaction()	string	The reaction emoji (e.g., "😀", "👍")
count	getCount()	number	Number of users who reacted with this reaction
reactedByMe	getReactedByMe()	boolean	Whether the logged-in user reacted with this reaction

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ReactionEvent

ReactionEvent represents a real-time reaction event. It is received via the onMessageReactionAdded and onMessageReactionRemoved listener callbacks.

Properties

Property	Getter	Return Type	Description
reaction	getReaction()	Reaction	The reaction details object
receiverId	getReceiverId()	string	UID or GUID of the receiver
receiverType	getReceiverType()	string	Receiver type ("user" or "group")
conversationId	getConversationId()	string	ID of the conversation
parentMessageId	getParentMessageId()	string	ID of the parent message (if the reacted message is in a thread)

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TypingIndicator

TypingIndicator represents a typing event. It is received via the onTypingStarted and onTypingEnded listener callbacks.

Properties

Property	Getter	Return Type	Description
receiverId	getReceiverId()	string	UID or GUID of the receiver
receiverType	getReceiverType()	string	Receiver type ("user" or "group")
sender	getSender()	User	The user who is typing
metadata	getMetadata()	Object	Custom metadata attached to the typing indicator

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TransientMessage

TransientMessage represents a transient (non-persistent) message. It is received via the onTransientMessageReceived listener callback. Transient messages are not stored on the server.

Properties

Property	Getter	Return Type	Description
receiverId	getReceiverId()	string	UID or GUID of the receiver
receiverType	getReceiverType()	string	Receiver type ("user" or "group")
sender	getSender()	User	The user who sent the transient message
data	getData()	any	Custom data payload of the transient message

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Attachment

Attachment represents a file attachment on a MediaMessage. It is available via getAttachment() or getAttachments() on a MediaMessage object.

Properties

Property	Getter	Return Type	Description
name	getName()	string	Name of the file
extension	getExtension()	string	File extension (e.g., "png", "pdf")
mimeType	getMimeType()	string	MIME type of the file (e.g., "image/png")
size	getSize()	number	Size of the file in bytes
url	getUrl()	string	URL to download the file

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CometChatException

CometChatException represents an error from the Chat SDK. It is received in rejection callbacks of promise-based SDK methods (e.g., sendMessage, login, getGroup).

Properties

Property	Type	Description
code	string | number	Error code identifying the type of error
name	string	Name/category of the error
message	string	Human-readable error description
details	string	Additional error details