Message threads

The message threads feature organizes conversations into threads, making it easier to follow and respond to specific topics.

Users need threads to:

• Set topic-specific discussions - within group chats or 1:1 conversations, you can initiate or participate in separate threads dedicated to specific topics, ensuring focused and structured discussions.

• Clarify and resolve issues - message threads let you address specific problems or questions within a conversation, allowing you to provide relevant input and ensure clarity and efficient problem-solving.

• Reduce confusion - by allowing you to focus the conversation in a separate thread, you minimize cross-talk and make the conversation easier to follow.

In the Chat SDK, a thread is a separate channel created for a selected message. Such a thread channel gets the ID starting with PUBNUB_INTERNAL_THREAD followed by the channel ID and message ID (separated by underscores). The message for which you create a thread channel has the hasThread parameter set to true to distinguish it from other messages. All messages in a thread (thread messages) are ordered by timetokens containing info on when messages were published.

Each thread message and thread channel are separate entities in the Chat SDK that extend the Message and Channel entities. This means that they offer separate methods for handling threads but also let you use all methods under the Message and Channel entities (for example, for editing or deleting).

Create thread

createThread() creates a thread (channel) for a selected message.

Method signature

This method has the following signature:

createThread() async throws -> ThreadChannelImpl

Input

This method doesn't take any parameters.

Output

Parameter	Description
ThreadChannelImpl	Object returning the thread channel metadata for the message updated with the hasThread parameter (and a threadRootId action type underneath).

Basic usage

Sample code

The code samples in Swift Chat SDK focus on asynchronous code execution.

You can also write synchronous code as the parameters are shared between the async and sync methods but we don't provide usage examples of such.

Create a thread for a message on the support channel.

// Assuming you have a reference of type "ChatImpl" named "chat"
Task {
  if let channel = try await chat.getChannel(channelId: "support") {
    // Timetoken for the message you're trying to get
    let timetoken: Timetoken = 16200000000000001
    // Get the message with the specified timetoken
    if let message = try await channel.getMessage(timetoken: timetoken) {
      let threadChannel = try await message.createThread()
      debugPrint("Thread created successfully with ID: \(threadChannel.id)")
      debugPrint("Parent channel ID: \(threadChannel.parentChannelId)")
    } else {
      debugPrint("No message found with this timetoken")
    }
  } else {
    debugPrint("Channel not found")

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Send thread message

Reply to a message in a thread by calling the sendText() method from the previously created ThreadChannel object.

Method signature

Head over to the sendText() method section for details.

Basic usage

Sample code

The code samples in Swift Chat SDK focus on asynchronous code execution.

You can also write synchronous code as the parameters are shared between the async and sync methods but we don't provide usage examples of such.

Send a message in a thread created for the last message on the support channel.

// Assuming you have a reference of type "ChatImpl" named "chat"
Task {
  if let channel = try await chat.getChannel(channelId: "support") {
    // Timetoken for the message you're trying to get
    let timetoken: Timetoken = 16200000000000001
    // Get the message with the specified timetoken
    if let message = try await channel.getMessage(timetoken: timetoken) {
      // Get the thread channel for a given message
      let threadChannel = try await message.getThread()
      // Send a new message to the thread channel
      let replyInThreadTimetoken = try await threadChannel.sendText(text: "Good job, guys!")
      // Print the timetoken of the message that has been sent
      debugPrint("Reply in a thread successfuly sent at \(replyInThreadTimetoken)")
    } else {
      debugPrint("No message found with this timetoken")

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Get thread

Get the thread channel on which the thread message is published.

Method signature

This method has the following signature:

message.getThread() async throws -> ThreadChannelImpl

Input

This method doesn't take any parameters.

Output

Type	Description
ThreadChannelImpl	Object returning the thread channel metadata.

Basic usage

Sample code

The code samples in Swift Chat SDK focus on asynchronous code execution.

You can also write synchronous code as the parameters are shared between the async and sync methods but we don't provide usage examples of such.

Get the thread channel created from the message with the 16200000000000001 timetoken.

// Assuming you have a reference of type "ChatImpl" named "chat"
Task {
  if let channel = try await chat.getChannel(channelId: "support") {
    // Timetoken for the message you're trying to get
    let timetoken: Timetoken = 16200000000000001
    // Get the message with the specified timetoken
    if let message = try await channel.getMessage(timetoken: timetoken) {
      let threadChannel = try await message.getThread()
      debugPrint("Thread channel ID: \(threadChannel.id)")
      debugPrint("Parent channel ID: \(threadChannel.parentChannelId)")
    } else {
      debugPrint("No message found with this timetoken")
    }
  } else {
    debugPrint("Channel not found")

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Check if message starts thread

You can access the hasThread property of the Message object to check if a given message starts a thread.

Basic usage

Sample code

The code samples in Swift Chat SDK focus on asynchronous code execution.

You can also write synchronous code as the parameters are shared between the async and sync methods but we don't provide usage examples of such.

Check if the message with the 16200000000000001 timetoken starts a thread.

// Assuming you have a reference of type "ChatImpl" named "chat"
Task {
  if let channel = try await chat.getChannel(channelId: "support") {
    // Timetoken for the message you're trying to get
    let timetoken: Timetoken = 16200000000000001
    // Get the message with the specified timetoken
    if let message = try await channel.getMessage(timetoken: timetoken) {
      debugPrint("Message fetched successfully: \(message.text)")
      debugPrint("Does this message have a thread: \(message.hasThread)")
    } else {
      debugPrint("No message found with this timetoken")
    }
  } else {
    debugPrint("Channel not found")
  }

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Get thread message updates

You can receive updates when specific message threads and related message reactions are added, edited, or removed on other clients using the streamUpdatesOn() on the ThreadMessage class.

This method returns an asynchronous stream which produces a new value whenever someone adds, edits or deletes a message, or adds or removes a message reaction to/from a list of thread messages.

Underneath, this method subscribes the current user to a channel and adds a message reactions event listener to receive all messageAction events of type added or removed.

Method signature

This method takes the following parameters:

ThreadMessageImpl.streamUpdatesOn(messages: [ThreadMessageImpl]) -> AsyncStream<[ThreadMessageImpl]>

Input

* required

Parameter	Description
messages * Type: [ThreadMessageImpl] Default: n/a	Collection of ThreadMessageImpl objects for which you want to get updates on changed message threads or related message reactions.

Output

Parameter	Description
AsyncStream<[ThreadMessageImpl]>	An asynchronous stream that produces updates when any item in the messages collection is updated.

Basic usage

Sample code

The code samples in Swift Chat SDK focus on asynchronous code execution.

You can also write synchronous code as the parameters are shared between the async and sync methods but we don't provide usage examples of such.

Get message threads and message reaction-related updates for the first page of messages published in a thread on the support channel.

AsyncStream

// Assuming you have a reference of type "ThreadChannelImpl" named "threadChannel"
Task {
  if let threadMessage = try await threadChannel.getHistory(count: 1).messages.first {
    for await receivedThreadMessages in ThreadMessageImpl.streamUpdatesOn(messages: [threadMessage]) {
      debugPrint("Received elements: \(receivedThreadMessages)")
    }
  } else {
    debugPrint("Message not found")
  }
}

Closure

// Important: Keep a strong reference to the returned "AutoCloseable" object as long as you want
// to receive updates. If the "AutoCloseable" is deallocated, the stream will be cancelled, 
// and no further items will be produced. You can also stop receiving updates manually
// by calling the "close()" method on the "AutoCloseable" object.

// Assuming you have a reference of type "ThreadMessageImpl" named "threadMessage"
autoCloseable = ThreadMessageImpl.streamUpdatesOn(messages: [threadMessage]) { updatedThreadMessages in
  updatedThreadMessages.forEach { updatedThreadMessage in
    debugPrint("-=Updated thread message: \(updatedThreadMessage)")
  }
}

Get thread channel updates

You can receive updates when specific ThreadChannel object(s) are edited or removed on other clients using the streamUpdatesOn() method that checks updates on a channel list and it's tied to the ThreadChannel class.

This method returns an asynchronous stream which produces a new value whenever someone adds, changes, or removes channel thread metadata.

Underneath, this method subscribes the current user to a channel and add an objects event listener to receive all objects events of type channel.

Method signature

This method takes the following parameters:

ThreadChannelImpl.streamUpdatesOn(
    channels: [ThreadChannelImpl],
) -> AsyncStream<[ThreadChannelImpl]>

Input

* required

Parameter	Description
channels * Type: ThreadChannelImpl] Default: n/a	Array of ThreadChannelImpl objects for which you want to get updates on changed channel threads.

Output

Parameter	Description
AsyncStream<[ThreadChannelImpl]>	An asynchronous stream that produces updates when any item in the channels collection is updated.

Basic usage

Sample code

The code samples in Swift Chat SDK focus on asynchronous code execution.

You can also write synchronous code as the parameters are shared between the async and sync methods but we don't provide usage examples of such.

AsyncStream

// Assuming you have two references, "threadChannel" and "anotherThreadChannel", of type "ThreadChannelImpl"
Task {
  for await updatedThreadChannel in ThreadChannelImpl.streamUpdatesOn(channels: [threadChannel, anotherThreadChannel]) {
    debugPrint("Updated thread channel: \(updatedThreadChannel)")
  }
}

Closure

// Important: Keep a strong reference to the returned "AutoCloseable" object as long as you want
// to receive new updates. If the "AutoCloseable" is deallocated, the stream will be cancelled,
// and no further items will be produced. You can also stop receiving updates manually
// by calling the "close()" method on the "AutoCloseable" object.

// Assuming you have an array of "ThreadChannelImpl" objects named "threadChannels
autoCloseable = ThreadChannelImpl.streamUpdatesOn(channels: threadChannels) { updatedThreadChannels in
  updatedThreadChannels.forEach { updatedThreadChannel in
    debugPrint("Updated thread channel: \(updatedThreadChannel)")
  }
}

Get historical thread message

getHistory() called on the ThreadChannel object fetches historical thread messages from that thread channel.

Method signature

This method takes the following parameters:

threadChannel.getHistory(
    startTimetoken: Timetoken? = nil,
    endTimetoken: Timetoken? = nil,
    count: Int = 25
  ) async throws -> (messages: [ThreadMessageImpl], isMore: Bool)

Input

* required

Parameter	Description
startTimetoken Type: Timetoken Default: n/a	Timetoken delimiting the start of a time slice (exclusive) to pull thread messages from. For details, refer to the Fetch History section.
endTimetoken Type: Timetoken Default: n/a	Timetoken delimiting the end of a time slice (inclusive) to pull thread messages from. For details, refer to the Fetch History section.
count * Type: Int Default: 25	Number of historical thread messages to return for the channel in a single call. Since each call returns all attached message reactions by default, the maximum number of returned thread messages is 25. For more details, refer to the description of the includeMessageActions parameter in the Swift SDK docs.

Output

Parameter	Description
(messages: [ThreadMessageImpl], isMore: Bool) Type: object	A tuple containing a list of ThreadMessageImpl objects and a boolean flag indicating if there are more messages available.

By default, each call returns all message reactions and metadata attached to the retrieved thread messages.

Basic usage

Sample code

The code samples in Swift Chat SDK focus on asynchronous code execution.

You can also write synchronous code as the parameters are shared between the async and sync methods but we don't provide usage examples of such.

Fetch 10 historical thread messages that are older than the timetoken 15343325214676133.

// Assuming you have a reference of type "ThreadChannelImpl" named "threadChannel"
Task {
  let response = try await threadChannel.getHistory(
    startTimetoken: 15343325214676133,
    count: 10
  )
  response.messages.forEach { message in
    debugPrint("Thread message: \(message.channelId) - \(message.text)")
  }

  // The code below demonstrates how to fetch the next page of messages. Skip it if you're only 
  // interested in the initial set.

  // Retrieves the timetoken of the oldest message from the previous response
  let theOldestTimetoken = response.messages.compactMap { $0.timetoken }.min()

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Remove thread

removeThread() removes a thread (channel) for a selected message.

Method signature

This method has the following signature:

message.removeThread() async throws -> ChannelImpl

Input

This method doesn't take any parameters.

Output

Parameter	Description
ChannelImpl	The updated channel object after the removal of the thread.

Basic usage

Sample code

The code samples in Swift Chat SDK focus on asynchronous code execution.

You can also write synchronous code as the parameters are shared between the async and sync methods but we don't provide usage examples of such.

Remove a thread for the last message on the support channel.

// Assuming you have a reference of type "ChatImpl" named "chat"
Task {
  if let channel = try await chat.getChannel(channelId: "support") {
    if let message = try await channel.getHistory(count: 1).messages.first {
      let updatedChannel = try await message.removeThread()
      debugPrint("Thread removed successfully.")
      debugPrint("Updated Channel: \(String(describing: updatedChannel))")
    } else {
      debugPrint("Message not found")
    }
  } else {
    debugPrint("Channel not found")
  }
}

Pin thread message to thread channel

pinMessage() called on the ThreadChannel object pins a selected thread message to the thread channel.

Method signature

This method takes the following parameters:

threadChannel.pinMessage(
    message: MessageImpl 
) async throws -> ThreadChannelImpl

Input

* required

Parameter	Description
message * Type: MessageImpl Default: n/a	MessageImpl object you want to pin to the selected thread channel.

Output

Parameter	Description
ThreadChannelImpl	Object returning the thread channel metadata updated with these custom fields: pinnedMessageTimetoken to mark the timetoken when the message was pinned pinnedMessageChannelID to mark the channel on which the message was pinned to the thread channel (unpinning was performed either directly on the parent channel or on a thread channel).

Basic usage

Sample code

The code samples in Swift Chat SDK focus on asynchronous code execution.

You can also write synchronous code as the parameters are shared between the async and sync methods but we don't provide usage examples of such.

A thread was created for the last message in the support parent channel. Pin the last message from this thread to the thread channel.

// Assuming you have a reference of type "ChatImpl" named "chat"
Task {
  if let channel = try await chat.getChannel(channelId: "support") {
    // Get the last message on the channel, which is the root message for the thread
    if let message = try await channel.getHistory(count: 1).messages.first {
      // Get the thread channel
      let threadChannel = try await message.getThread()
      // Get the last message on the thread channel
      if let threadMessage = try await threadChannel.getHistory(count: 1).messages.first {
        // Pin the message from the thread to the thread channel
        let updatedChannel = try await threadChannel.pinMessage(message: threadMessage)
        // Prints the updated channel object
        debugPrint("Updated channel object: \(updatedChannel)")
      } else {
        debugPrint("No messages found in the thread channel.")

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Pin thread message to parent channel

You can pin a selected thread message to the parent channel with pinMessageToParentChannel() and pinToParentChannel(). They give the same output, and the only difference is that you call a given method either on the ThreadChannel or the ThreadMessage object. Depending on the object, these methods take different input parameters - you have to specify the thread message you want to pin or not because it's already known.

Method signature

These methods take the following parameters:

• pinMessageToParentChannel() (on the ThreadChannel object)

  threadChannel.pinMessageToParentChannel(
      message: ThreadMessageImpl
  ) async throws -> ChannelImpl

• pinToParentChannel() (on the ThreadMessage object)

  threadMessage.pinToParentChannel() async throws -> ChannelImpl

Input

Parameter	Required in pinMessageToParentChannel()	Required in pinToParentChannel()	Description
message Type: ThreadMessageImpl Default: n/a	Yes	No	ThreadMessageImpl object you want to pin to the selected parent channel.

Output

Parameter	Description
ChannelImpl	Object returning the channel metadata updated with these custom fields: pinnedMessageTimetoken to mark the timetoken when the message was pinned pinnedMessageChannelID to mark the channel on which the message was pinned to the parent channel (pinning was performed either directly on the parent channel or on a thread channel).

Basic usage

Sample code

The code samples in Swift Chat SDK focus on asynchronous code execution.

You can also write synchronous code as the parameters are shared between the async and sync methods but we don't provide usage examples of such.

A thread was created for the last message in the support parent channel. Pin the last message from this thread to the parent channel.

• pinMessageToParentChannel()

  // Assuming you have a reference of type "ChatImpl" named "chat"
  Task {
    if let channel = try await chat.getChannel(channelId: "support") {
      // Get the last message on the channel, which is the root message for the thread
      if let message = try await channel.getHistory(count: 1).messages.first {
        // Get the thread channel
        let threadChannel = try await message.getThread()
        // Get the last message on the thread channel
        if let threadMessage = try await threadChannel.getHistory(count: 1).messages.first {
          // Pin the message to the parent channel
          let updatedChannel = try await threadChannel.pinMessageToParentChannel(message: threadMessage)
          debugPrint("Message pinned successfully to the parent channel")
          debugPrint("Updated channel object: \(updatedChannel)")
        } else {
          debugPrint("No messages found in the thread channel")

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• pinToParentChannel()

  // Assuming you have a reference of type "ChatImpl" named "chat"
  Task {
    if let channel = try await chat.getChannel(channelId: "support") {
      // Get the last message on the channel, which is the root message for the thread
      if let message = try await channel.getHistory(count: 1).messages.first {
        // Get the thread channel
        let threadChannel = try await message.getThread()
        // Get the last message on the thread channel
        if let threadMessage = try await threadChannel.getHistory(count: 1).messages.first {
          // Pin the message to the parent channel
          let updatedChannel = try await threadMessage.pinToParentChannel()
          debugPrint("Message pinned successfully to the parent channel")
          debugPrint("Updated channel object: \(updatedChannel)")
        } else {
          debugPrint("No messages found in the thread channel")

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Unpin thread message from thread channel

unpinMessage() called on the ThreadChannel object unpins the previously pinned thread message from the thread channel.

Method signature

This method has the following signature:

threadChannel.unpinMessage() async throws -> ThreadChannelImpl

Input

This method doesn't take any parameters.

Output

Parameter	Description
ThreadChannelImpl	Object returning the thread channel metadata updated with these custom fields: pinnedMessageTimetoken to mark the timetoken when the message was unpinned pinnedMessageChannelID to mark the channel on which the message was unpinned from the thread channel (unpinning was performed either directly on the parent channel or on a thread channel).

Basic usage

Sample code

The code samples in Swift Chat SDK focus on asynchronous code execution.

You can also write synchronous code as the parameters are shared between the async and sync methods but we don't provide usage examples of such.

Unpin the thread message from the thread (channel) created for the last message on the support channel.

    // Assuming you have a reference of type "ChatImpl" named "chat"
    Task {
      if let channel = try await chat.getChannel(channelId: "support") {
        // Get the last message on the channel, which is the root message for the thread
        if let message = try await channel.getHistory(count: 1).messages.first {
          // Get the thread channel
          let threadChannel = try await message.getThread()
          // Get the last message on the thread channel
          if let threadMessage = try await threadChannel.getHistory(count: 1).messages.first {
            let updatedChannel = try await threadChannel.unpinMessage()
            debugPrint("Message unpinned successfully from the thread channel")
            debugPrint("Updated channel object: \(updatedChannel)")
          } else {
            debugPrint("No messages found in the thread channel.")
          }

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Unpin thread message from parent channel

You can unpin the previously pinned thread message from the parent channel with unpinMessageFromParentChannel() and unpinFromParentChannel().

Method signature

These methods have the following signatures:

• unpinMessageFromParentChannel() (on the ThreadChannel object)

  threadChannel.unpinMessageFromParentChannel() -> ChannelImpl

• unpinFromParentChannel() (on the ThreadMessage object)

  threadMessage.unpinFromParentChannel() -> ChannelImpl

Input

These methods don't take any parameters.

Output

Parameter	Description
ChannelImpl	Object returning the channel metadata updated with these custom fields: pinnedMessageTimetoken to mark the timetoken when the message was unpinned pinnedMessageChannelID to mark the channel on which the message was unpinned from the parent channel (unpinning was performed either directly on the parent channel or on a thread channel).

Basic usage

Sample code

The code samples in Swift Chat SDK focus on asynchronous code execution.

You can also write synchronous code as the parameters are shared between the async and sync methods but we don't provide usage examples of such.

Unpin the thread message from the support parent channel.

• unpinMessageFromParentChannel()

  // Assuming you have a reference of type "ChatImpl" named "chat"
  Task {
    if let channel = try await chat.getChannel(channelId: "support") {
      // Get the last message on the channel, which is the root message for the thread
      if let message = try await channel.getHistory(count: 1).messages.first {
        // Get the thread channel
        let threadChannel = try await message.getThread()
        // Get the last message on the thread channel
        if let threadMessage = try await threadChannel.getHistory(count: 1).messages.first {
          let updatedChannel = try await threadChannel.unpinMessageFromParentChannel()
          debugPrint("Message unpinned successfully from the parent channel")
          debugPrint("Updated channel object: \(updatedChannel)")
        } else {
          debugPrint("No messages found in the thread channel")
        }

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• unpinFromParentChannel()

  Task {
    if let channel = try await chat.getChannel(channelId: "support") {
      // Get the last message on the channel, which is the root message for the thread
      if let message = try await channel.getHistory(count: 1).messages.first {
        // Get the thread channel
        let threadChannel = try await message.getThread()
        // Get the last message on the thread channel
        if let threadMessage = try await threadChannel.getHistory(count: 1).messages.first {
          let updatedChannel = try await threadMessage.unpinFromParentChannel()
          debugPrint("Message unpinned successfully from the parent channel")
          debugPrint("Updated channel object: \(updatedChannel)")
        } else {
          debugPrint("No messages found in the thread channel")
        }
      } else {

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