Offline Support

The offline library provides a caching mechanism applied automatically to some of the ChatClient functions as side effects. The offline results, as well as online results, are being exposed through StateFlow objects that can be observed for changes.

Configuration

When using the offline library, you first have to provide the OfflinePlugin to ChatClient as described on the Getting Started page:

Kotlin

val offlinePluginFactory = StreamOfflinePluginFactory(
    config = Config(
        backgroundSyncEnabled = true,
        userPresence = true,
        persistenceEnabled = true,
        uploadAttachmentsNetworkType = UploadAttachmentsNetworkType.NOT_ROAMING,
        useSequentialEventHandler = false,
    ),
    appContext = context,
)

ChatClient.Builder(apiKey, context).withPlugin(offlinePluginFactory).build()

Java

// Enables background sync which is performed to sync user actions done while offline.
boolean backgroundSyncEnabled = true;
// Enables the ability to receive information about user activity such as last active date and if they are online right now.
boolean userPresence = true;
// Enables using the database as an internal caching mechanism.
boolean persistenceEnabled = true;
// An enumeration of various network types used as a constraint inside upload attachments worker.
UploadAttachmentsNetworkType uploadAttachmentsNetworkType = UploadAttachmentsNetworkType.NOT_ROAMING;
// Whether the SDK will use a new sequential event handling mechanism.
boolean useSequentialEventHandler = false;

StreamOfflinePluginFactory offlinePluginFactory = new StreamOfflinePluginFactory(new Config(backgroundSyncEnabled, userPresence, persistenceEnabled, uploadAttachmentsNetworkType, useSequentialEventHandler), context);
new ChatClient.Builder("apiKey", context).withPlugin(offlinePluginFactory).build();

You can configure some of the OfflinePlugin options using the Config class provided to the StreamOfflinePluginFactory. You can use the following properties:

• backgroundSyncEnabled - Enables the background sync which is performed to sync user actions, such as sending the message, done without an active Internet connection.
• userPresence - Enables the ability to receive information about user activity such as last active date and if they are online right now.
• persistenceEnabled - Enables using the database as an internal caching mechanism. You can disable it if you want to have access to the StateFlows but you only want to keep the data in the memory.
• uploadAttachmentsNetworkType - An enumeration of various network types used as a constraint inside upload attachments worker. Upload attachments might be heavy work so we allow restricting whether the job can be performed.

State

The offline library gives you access to a few objects responsible for exposing the state to a particular situation:

• QueryChannelsState contains state related to a single query channels request. You can use it to collect information after performing the query channels request.
• ChannelState contains state related to a single channel. You can use it to access channel related data after performing a watch channel request.
• ThreadState contains state for a single thread within the channel.
• GlobalState contains global information for the current user such as connection state, mutes, unread counts, etc.

You can access the objects mentioned above like this:

Kotlin

// Returns QueryChannelsState object based on filter and sort used to query channels
val queryChannelsState = chatClient.state.queryChannels(filter = filter, sort = sort)

// Returns ChannelState object for a given channel
val channelState = chatClient.state.channel(channelType = "messaging", channelId = "sampleId")

// Returns ThreadState object for a thread associated with a given parentMessageId
val threadState = chatClient.state.thread(messageId = "parentMessageId")

// Gives you access to GlobalState object
val globalState = chatClient.globalState

Java

// Returns QueryChannelsState object based on filter and sort used to query channels
QueryChannelsState queryChannelsState = ChatClientExtensions.getState(chatClient).queryChannels(filter, sort);

// Returns ChannelState object for a given channel
ChannelState channelState = ChatClientExtensions.getState(chatClient).channel("messaging", "sampleId");

// Returns ThreadState object for a thread associated with a given parentMessageId
ThreadState threadState = ChatClientExtensions.getState(chatClient).thread("parentMessageId");

// Gives you access to GlobalState object
GlobalState globalState = ChatClientExtensions.getGlobalState(chatClient);

danger

You should make sure that the user is connected before using the state. Accessing chatClient.state before connecting the user will result in a crash.

Methods mentioned above return a state object associated with the API call but don't perform the API call itself. If you don't want to bother yourself about doing API calls when using state objects, you can use one of the provided extension functions:

Kotlin

// Returns StateFlow<QueryChannelsState?> object and performs queryChannels request
val queryChannelsState: StateFlow<QueryChannelsState?> = chatClient.queryChannelsAsState(request = queryChannelsRequest, coroutineScope = scope)

// Returns StateFlow<ChannelState?> object and performs watchChannel request
val channelState: StateFlow<ChannelState?> = chatClient.watchChannelAsState(cid = "messaging:sampleId", messageLimit = 30, coroutineScope = scope)

// Returns ThreadState object for a thread associated with a given parentMessageId
val threadState: ThreadState = chatClient.getRepliesAsState(messageId = "messaging:sampleId", messageLimit = 30, coroutineScope = scope)

Java

// Returns LiveData<QueryChannelsState> object and performs queryChannels request
StateFlow<QueryChannelsState> queryChannelsStateStateFlow = ChatClientExtensions.queryChannelsAsState(chatClient, queryChannelsRequest);
LiveData<QueryChannelsState> queryChannelsStateLiveData = FlowExtensions.asLiveData(queryChannelsStateStateFlow);

// Returns LiveData<ChannelState> object and performs watchChannel request
StateFlow<ChannelState> channelStateStateFlow = ChatClientExtensions.watchChannelAsState(chatClient, "messaging:sampleId", 30);
LiveData<ChannelState> channelStateLiveData = FlowExtensions.asLiveData(channelStateStateFlow);

// Returns ThreadState object for a thread associated with a given parentMessageId
ThreadState threadState = ChatClientExtensions.getRepliesAsState(chatClient, "messaging:sampleId", 30);

Supported Operations

The offline library allows you to perform the following actions without the Internet connection:

• Creating a channel
• Sending, updating and deleting a message
• Sending and deleting reactions