omni::connect::core::LiveSessionChannel

Defined in omni/connect/core/LiveSessionChannel.h

Structs

Message: Live session channel message structure.
User: Live session channel user structure.

class LiveSessionChannel

An interface class for the live session message channel.

The channel class implementation handles interaction with an Omniverse Nucleus channel, which is a mechanism to broadcast messages to all connected clients. When messages are received it will queue them, allowing the client to poll for them any time. When messages that specifically identify connected users are received, this class will maintain a list of connected users which the client can also poll.

This class also has a state machine that will automatically respond to Join and GetUsers messages from other clients with a Hello message.

This class does not run message processing in a dedicated thread, so processMessages() is is used to process the Join/Hello state machine and populate the user list.

Note

The static factory method create() returns a std::shared_ptr so object lifetime is managed by scope.

Public Types

enum class MessageType

Live session channel message types.

Values:

enumerator eJoin: Sent by the Channel class when joining a channel.

enumerator eHello: Sent as a response when another client sends a Join or GetUsers message.

enumerator eGetUsers: Sent by a client to determine what users are in the session.

enumerator eLeft: Sent when the user leaves the channel.

enumerator eMergeStarted: Sent when the Admin client is starting the merge process. When clients receive this message they should immediately disable further changes to the .live layer.

enumerator eMergeFinished: Sent when the merge is complete.

enumerator eInvalid: Invalid message.

using Messages = std::vector<Message>: A list of channel messages.

using Users = std::vector<User>: A list of channel users.

Public Functions

~LiveSessionChannel()

bool isConnected() const

Check if the channel is connected to an actual Nucleus channel file.

Returns: Whether the channel is connected

bool sendMessage(MessageType messageType) const

Send a channel message.

Parameters: messageType – The type of message to send
Returns: Whether the message was sent correctly

Messages processMessages()

Process and retrieve all of the pending channel messages.

This function drives the state machine that responds to other clients and populates the connected users list. It must be run periodically.

Note

It is safe to call this function from multiple threads simultaneously, the internal user and message queues are protected by mutexes.

Returns: A list of received messages

Users getUsers(bool includeSelf) const

Get all of the connected users.

Parameters: includeSelf – Whether to include this client user in list
Returns: A list of connected users

User getUser() const

Get this client user.

Returns: This client user

void leaveChannel()

Leave the channel.

This function will only send a “Left” message if sendJoinMessage was true in create()

Public Static Functions

static std::shared_ptr<LiveSessionChannel> create(const std::string &uri, bool sendJoinMessage = true)

Create and join an Omniverse live session message channel.

This is a factory to create and join a LiveSessionChannel. There is no join() method.

Note

Call omni::connect::core::startup() before this function to initialize required components

Parameters

uri – The URI of the Nucleus channel (session.channel)
sendJoinMessage – If true a Join message will be broadcast on the channel. Use false to “peek” into a channel to see connected users.

Returns

A channel interface shared pointer (std::shared_ptr<LiveSessionChannel>)

static const char *getMessageTypeName(LiveSessionChannel::MessageType messageType)

Convert a live session channel message type to a string.

Parameters: messageType – The type of message to convert to a string
Returns: A string value for the message type

struct Message

Live session channel message structure.

This consists of all of the data that a live session message contains (message type and sending user)

Public Members

MessageType type: The message type (Join, Left, MergeStarted, etc.)

User user: The user that sent the message.

struct User

Live session channel user structure.

When a message is received this information will identify a client

Public Members

std::string id: The user ID assigned by the Omniverse Client Library, eg. WD34WRMUJHLU7Q1M

std::string name: The user name used to connect to the Nucleus server.

std::string app: The name of the application used to connect to live session.