# Chat > Built on top of the core Meeting Place SDK that utilises Decentralised Identifier (DID) and DIDComm Messaging v2.1 protocol to send secure and private messages with end-to-end encryption. ## Install Dependency Package: meeting_place_chat ```bash dart pub add meeting_place_chat ``` Check the latest version on the [pub.dev registry](https://pub.dev/packages/meeting_place_chat) or view the source on [GitHub](https://github.com/affinidi/affinidi-meetingplace-sdk-dart/tree/main/packages/meeting_place_chat). ## Classes and Methods ### MeetingPlaceChatSDK The MeetingPlaceChatSDK is a high-level API for secure messaging in the Meeting Place ecosystem. It supports individual DIDComm channels only. Group channels are not supported by this package — use the Matrix SDK for group messaging. Built on top of the core Meeting Place SDK, it uses Decentralised Identifiers (DID) and the DIDComm v2.1 protocol to ensure private, end-to-end encrypted communication. #### initialiseChatFromChannel A static method that creates an instance of MeetingPlaceChatSDK for the provided channel. Parameters channel Channel Required The Channel entity representing the chat. coreSDK MeetingPlaceCoreSDK Required Instance of MeetingPlaceCoreSDK to retrieve group information if needed. chatRepository ChatRepository Required The ChatRepository used for persisting messages. options MeetingPlaceChatSDKOptions Required Configuration options for the chat. card ContactCard Optional Optional contact card representing the user profile. logger MeetingPlaceChatSDKLogger Optional Optional logger implementation for custom logging behaviour. Example ```dart import 'package:meeting_place_core/meeting_place_core.dart'; import 'package:meeting_place_chat/meeting_place_chat.dart'; // Create a channel instance — only ChannelType.individual is supported. final Channel channel = Channel( type: ChannelType.individual, permanentChannelDid: 'did:example:123', otherPartyPermanentChannelDid: 'did:example:456', mediatorDid: 'did:example:mediator', offerLink: 'offer-link-value', // ...other required fields ); final chatSDK = await MeetingPlaceChatSDK.initialiseChatFromChannel( channel, coreSDK: coreSDK, chatRepository: await ref.read(chatItemsRepositoryDriftProvider.future), options: MeetingPlaceChatSDKOptions(presenceExpiresInSeconds: 3), card: identityContactCard, ); ``` #### startChatSession Starts a new chat session. - Initializes ChatStreamManager. - Subscribes to the mediator channel. - Loads persisted messages from repository. - Triggers a profile hash sync. Parameters No parameters required. Example ```dart import 'package:meeting_place_core/meeting_place_core.dart'; import 'package:meeting_place_chat/meeting_place_chat.dart'; final chatSDK = await MeetingPlaceChatSDK.initialiseChatFromChannel( ... ); final startSession = await chatSDK.startChatSession(); ``` #### endChatSession Ends the chat session, disposing of the channel and stream manager. Parameters No parameters required. Example ```dart import 'package:meeting_place_core/meeting_place_core.dart'; import 'package:meeting_place_chat/meeting_place_chat.dart'; chatSDK.endChatSession(); ``` #### getMessageById Retrieves a single message by ID. Parameters messageId String Required A unique message identifier. Example ```dart import 'package:meeting_place_chat/meeting_place_chat.dart'; final messageId = ''; final ChatItem? message = await chatSDK.getMessageById(messageId); ``` #### sendChatContactDetailsUpdate Sends updated contact details from the current contact card. Parameters message ConciergeMessage Required Message of updated contact details. Example ```dart import 'package:meeting_place_core/meeting_place_core.dart'; import 'package:meeting_place_chat/meeting_place_chat.dart'; final ConciergeMessage updateMessage = ConciergeMessage( chatId: '', messageId: '', senderDid: '', isFromMe: true, // ...other required fields ); await chatSDK.sendChatContactDetailsUpdate(updateMessage); ``` #### sendTextMessage Sends a plain text message (optionally with attachments). Parameters text String Required The message content. attachments List Optional An optional list of attachments. Example ```dart import 'package:meeting_place_chat/meeting_place_chat.dart'; final Message sentMessage = await chatSDK.sendTextMessage( 'Hello, this is a test message!', ); ``` #### reactOnMessage Reacts (or unreacts) to a chat message with an emoji or symbol. Parameters message Message Required The target message. reaction String Required The reaction string (e.g., emoji). Example ```dart import 'package:meeting_place_core/meeting_place_core.dart'; import 'package:meeting_place_chat/meeting_place_chat.dart'; await chatSDK.reactOnMessage(message, reaction: reaction); ``` #### sendChatActivity Sends a chat activity message. Parameters No parameters required. Example ```dart import 'package:meeting_place_core/meeting_place_core.dart'; import 'package:meeting_place_chat/meeting_place_chat.dart'; await chatSDK.sendChatActivity(); ``` #### sendChatPresence Sends a “chat presence” signal (e.g., online status). Parameters No parameters required. Example ```dart import 'package:meeting_place_core/meeting_place_core.dart'; import 'package:meeting_place_chat/meeting_place_chat.dart'; await chatSDK.sendChatPresence(); ``` #### sendEffect Sends a special chat effect. Parameters effect Effect Required The effect to send. Possible values defined in enum are as follows: confetti, balloons, fireworks, hearts. Example ```dart import 'package:meeting_place_chat/meeting_place_chat.dart'; // Send confetti effect await chatSDK.sendEffect(Effect.confetti); ``` #### sendChatDeliveredMessage Sends a “delivered” acknowledgement for a received message. Parameters messageId String Required The unique identifier of the message to acknowledge. Example ```dart import 'package:meeting_place_chat/meeting_place_chat.dart'; // Send a "delivered" receipt using the message ID. await chatSDK.sendChatDeliveredMessage(''); ``` #### approveConnectionRequest Approves an incoming connection request. Parameters message ConciergeMessage Required A special type of ChatItem used to represent system or administrative messages that require user action. Example ```dart import 'package:meeting_place_core/meeting_place_core.dart'; import 'package:meeting_place_chat/meeting_place_chat.dart'; await chatSDK.approveConnectionRequest(message); ``` #### rejectConnectionRequest A special type of ChatItem used to represent system or administrative messages that require user action. Parameters message ConciergeMessage Required The ConciergeMessage requesting approval. Example ```dart import 'package:meeting_place_chat/meeting_place_chat.dart'; await chatSDK.rejectConnectionRequest(message); ``` #### rejectChatContactDetailsUpdate Rejects a contact details update and marks message as confirmed. Parameters message ConciergeMessage Required The ConciergeMessage rejecting details update. Example ```dart import 'package:meeting_place_core/meeting_place_core.dart'; import 'package:meeting_place_chat/meeting_place_chat.dart'; await chatSDK.rejectChatContactDetailsUpdate(message); ``` #### messages Retrieves all persisted messages for this chat. Parameters No parameters required. Example ```dart import 'package:meeting_place_core/meeting_place_core.dart'; import 'package:meeting_place_chat/meeting_place_chat.dart'; final List chatItems = await chatSDK.messages; ``` #### chatStreamSubscription Waits until the mediator channel subscription is ready. Stream of live chat events ([StreamData]) for this session. Parameters No parameters required. Example ```dart import 'package:meeting_place_chat/meeting_place_chat.dart'; final ChatStream? chatStream = await chatSDK.chatStreamSubscription; ```