query method

Future<ChannelState> query({ bool state = true, bool watch = false, bool presence = false, PaginationParams? messagesPagination, PaginationParams? membersPagination, PaginationParams? watchersPagination, bool preferOffline = false, })

Query the API, get messages, members or other channel fields.

Set preferOffline to true to avoid the API call if the data is already in the offline storage.

Implementation

Future<ChannelState> query({
  bool state = true,
  bool watch = false,
  bool presence = false,
  PaginationParams? messagesPagination,
  PaginationParams? membersPagination,
  PaginationParams? watchersPagination,
  bool preferOffline = false,
}) async {
  ChannelState? channelState;

  try {
    // If we prefer offline, we first try to get the channel state from the
    // offline storage.
    if (preferOffline && !watch && cid != null) {
      final persistenceClient = _client.chatPersistenceClient;
      if (persistenceClient != null) {
        final cachedState = await persistenceClient.getChannelStateByCid(
          cid!,
          messagePagination: messagesPagination,
        );

        // If the cached state contains messages, we can use it.
        if (cachedState.messages?.isNotEmpty == true) {
          channelState = cachedState;
        }
      }
    }

    // If we still don't have the channelState, we try to get it from the API.
    channelState ??= await _client.queryChannel(
      type,
      channelId: id,
      channelData: _extraData,
      state: state,
      watch: watch,
      presence: presence,
      messagesPagination: messagesPagination,
      membersPagination: membersPagination,
      watchersPagination: watchersPagination,
    );

    if (_id == null) {
      _id = channelState.channel!.id;
      _cid = channelState.channel!.cid;
    }

    // Initialize the channel state if it's not initialized yet.
    if (this.state == null) {
      _initState(channelState);
    } else {
      // Otherwise, we update the existing state with the new channel state.
      //
      // But, before updating the state, we check if we are querying around a
      // message, If we are, we have to truncate the state to avoid potential
      // gaps in the message sequence.
      final isQueryingAround = switch (messagesPagination) {
        PaginationParams(idAround: _?) => true,
        PaginationParams(createdAtAround: _?) => true,
        _ => false,
      };

      if (isQueryingAround) this.state?.truncate();
      this.state?.updateChannelState(channelState);
    }

    // Submit for delivery reporting only when fetching the latest messages.
    // This happens when no pagination params are provided (initial query).
    if (messagesPagination == null) {
      _client.channelDeliveryReporter.submitForDelivery([this]);
    }

    return channelState;
  } catch (e, stk) {
    // If we failed to get the channel state from the API and we were not
    // supposed to watch the channel, we will try to get the channel state
    // from the offline storage.
    if (watch == false) {
      if (_client.persistenceEnabled) {
        return _client.chatPersistenceClient!.getChannelStateByCid(
          cid!,
          messagePagination: messagesPagination,
        );
      }
    }

    // Otherwise, we will just rethrow the error.
    _initializedCompleter.safeCompleteError(e, stk);

    rethrow;
  }
}