Client class

This is the top-level entrypoint to the XMTP flutter SDK.

This client provides access to every user Conversation. See listConversations, streamConversations.

It also allows the user to create a new Conversation. See newConversation.

And once a Conversation has been acquired, it can be used to listMessages, streamMessages, and sendMessage.

Creating a Client Instance

The client has two constructors: createFromWallet and createFromKeys.

The first time a user uses a new device they should call createFromWallet. This will prompt them to sign a message that either creates a new identity (if they're new) or enables their existing identity (if they've used XMTP before). When this succeeds it configures the client with a bundle of keys that can be stored securely on the device.

  var client = await Client.createFromWallet(wallet);
  await mySecureStorage.save(client.keys);

The second time a user launches the app they should call createFromKeys using the stored keys from their previous session.

  var keys = await mySecureStorage.load();
  var client = await Client.createFromKeys(keys);

Caching / Offline Storage

The two primary models Conversation and DecodedMessage are designed with offline storage in mind. See the example app for a demonstration. TODO: consider adding offline storage support to the SDK itself.

Each Conversation is uniquely identified by its Conversation.topic. And each DecodedMessage is uniquely identified by its DecodedMessage.id. See note re "Offline Storage" atop DecodedMessage.

Implemented types

• Codec<DecodedContent>

Properties

address → EthereumAddress

final

contentType → ContentTypeId

This completes the implementation of the Codec interface.

no setter, override

hashCode → int

The hash code for this object.

no setter, inherited

keys → PrivateKeyBundle

no setter

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

Methods

canMessage(String address) → Future<bool>

Whether or not we can send messages to address.

decode(EncodedContent encoded) → Future<DecodedContent>

These use all registered codecs to decode and encode content.

override

decryptConversation(Envelope envelope) → Future<Conversation?>

This decrypts a Conversation from an envelope.

decryptMessage(Conversation conversation, Message message) → Future<DecodedMessage?>

This decrypts and decodes the message belonging to conversation.

encode(DecodedContent decoded) → Future<EncodedContent>

This is called to encode the content

override

fallback(DecodedContent content) → String?

This may provide text that can be displayed instead of the content. It can be used in contexts that do not support rendering a content type.

override

listBatchMessages(Iterable<Conversation> conversations, {Iterable<Pagination>? paginations, DateTime? start, DateTime? end, int? limit, SortDirection sort = xmtp.SortDirection.SORT_DIRECTION_DESCENDING}) → Future<List<DecodedMessage>>

This lists messages sent to the conversations. This is identical to listMessages except it pulls messages from multiple conversations in a single call.

listConversations({DateTime? start, DateTime? end, int? limit, SortDirection? sort = xmtp.SortDirection.SORT_DIRECTION_DESCENDING}) → Future<List<Conversation>>

This lists all the Conversations for the user.

listMessages(Conversation conversation, {DateTime? start, DateTime? end, int? limit, SortDirection sort = xmtp.SortDirection.SORT_DIRECTION_DESCENDING}) → Future<List<DecodedMessage>>

This lists messages sent to the conversation.

newConversation(String address, {String conversationId = "", Map<String, String> metadata = const <String, String>{}}) → Future<Conversation>

This creates or resumes a Conversation with address. If a conversationId is specified then that will distinguish multiple conversations with the same user. A new conversationId always creates a new conversation.

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

sendMessage(Conversation conversation, Object content, {ContentTypeId? contentType}) → Future<DecodedMessage>

This sends a new message to the conversation. It returns the DecodedMessage to simplify optimistic local updates. e.g. you can display the DecodedMessage immediately without having to wait for it to come back down the stream.

sendMessageEncoded(Conversation conversation, EncodedContent encoded) → Future<DecodedMessage?>

This sends the already encoded message to the conversation. This is identical to sendMessage but can be helpful when you have already encoded the message to send. If it cannot be decoded then it still sends but this returns null.

streamBatchMessages(Iterable<Conversation> conversations) → Stream<DecodedMessage>

This exposes a stream of new messages sent to any of the conversations.

streamConversations() → Stream<Conversation>

This exposes a stream of new Conversations for the user.

streamMessages(Conversation conversation) → Stream<DecodedMessage>

This exposes a stream of new messages sent to the conversation. For streaming multiple conversations, see streamBatchMessages.

terminate() → Future<void>

Terminate this client.

toString() → String

A string representation of this object.

inherited

Operators

operator ==(Object other) → bool

The equality operator.

inherited

Static Methods

createFromKeys(Api api, PrivateKeyBundle keys, {List<Codec<Object>> customCodecs = const []}) → Future<Client>

This creates a new Client using the saved keys from a previously successful authentication.

createFromWallet(Api api, Signer wallet, {List<Codec<Object>> customCodecs = const []}) → Future<Client>

This creates a new Client instance using the Signer to trigger signature prompts to acquire user authentication keys.