Muxy offers client-server and server-to-server communication through a messaging service. Extensions can publish and subscribe to messages on a named thread, and users with the "admin" role can broadcast messages to all viewers, or to selected sets of viewers.

Event subscriptions and notifications are handled slightly differently in different areas:

Debugging events report error information in the development environment.
Datastream events provide generic pub-sub message broadcasting.
State and configuration events report activity that affects stored state and configuration values for an extension.
Polling events report activity in a named viewer poll.
Transaction events report Twitch Bit Transaction activity involving an extension user.

Debugging events

In the development environment, the server reports errors through these messages. The extension does not need to subscribe, but must supply a handler for the error information contained in the message.

Function	Description	C# Signature
OnDebugMessageCallback	Handler signature for response to error notification. The Message contains the error number and description in JSON format.	`delegate void OnDebugMessageCallback` `(String` Message)
OnDebugMessage	Attach callback for debug messages.	`void OnDebugMessage` `(OnDebugMessageCallback` Callback)
DetachOnDebugMessage	Detach callback for debug messages.	`void DetachOnDebugMessage ()`

Datastream events

This system provides the ability to broadcast messages to subscribers on a per-channel or per-extension basis. Notification of broadcasts on the datastream contain the arbitrary message content in JSON format.

Function	Description	C# Signature
SendBroadcast	Broadcasts a message to subscribers in the Target scope, one of "STATE_TARGET_CHANNEL" or "STATE_TARGET_EXTENSION". Json contains the message body in JSON format.	`UInt16 SendBroadcast` `(string` Target, `string` Json)
DatastreamCallback	Handler signature for response to a message notification.	`delegate void DatastreamCallback (DatastreamUpdate` Update`)`
OnDatastream	Attach callback for message notification events. Use `SubscribeToDatastream()` to begin receiving message notifications.	`UInt32 OnDatastream (DatastreamCallback` Callback`)`
DetachOnDatastream	Attach callback for message notification events, passing the Handle returned from `OnDatastream()`.	`void DetachOnDatastream (UInt32` Handle`)`
SubscribeToDatastream	Subscribe to message notifications. Use after defining and attaching a handler with `OnDatastream()`	`UInt16 SubscribeToDatastream ()`
UnsubscribeFromDatastream	Unsubscribe from message notifications.	`UInt16 UnsubscribeFromDatastream ()`

State and Configuration Events

Muxy stores predefined and developer-defined state values on a per-channel or per-extension basis.
An extension can also define its own configuration options on a per-channel or per-extension basis, and store them separately from the standard state store. Each store contains key-value pairs in a JSON object.

See State and Configuration Handling.

Use the following functions to manage subscriptions and define responses to state and configuration update notifications.

Subscription-management functions must specify the target, one of CONFIG_TARGET_CHANNEL or CONFIG_TARGET_EXTENSION.
Update notifications report the type of operation performed. Update operations are: “add”, “remove”, “replace”, “move”, “copy”, “test”.

Function	Description	C# Signature
UpdateStateCallback	Handler signature for response to any update-state event.	`delegate void UpdateStateCallback` `(StateUpdate` Response)
OnStateUpdate	Attach callback for state update events. Use `SubscribeToStateUpdates()` to begin receiving update notifications.	`UInt32 OnStateUpdate` `(UpdateStateCallback` Callback)
DetachOnStateUpdate	Detach callback for state updates, passing the Handle returned from `OnStateUpdate()`.	`void DetachOnStateUpdate` `(UInt32` Handle)
SubscribeToStateUpdates	Subscribe to state update notifications for channel or extension. Use after defining and attaching a handler with `OnStateUpdate()`.	`UInt16 SubscribeToStateUpdates` `(string` Target)
UnsubscribeFromStateUpdates	Unsubscribe from state update notifications.	`UInt16 UnsubscribeFromStateUpdates` `(string` Target)
UpdateConfigCallback	Handler signature for response to any update-configuration event.	`delegate void UpdateConfigCallback` `(ConfigUpdate` Response)
OnConfigUpdate	Attach callback for configuration update events. Use `SubscribeToConfigUpdates()` to begin receiving update notifications.	`UInt32 OnConfigUpdate` `(UpdateConfigCallback` Callback)
DetachOnConfigUpdate	Detach callback for configuration updates, passing the Handle returned from `OnConfigUpdate()`.	`void DetachOnConfigUpdate` `(UInt32` Handle)
SubscribeToConfigurationChanges	Subscribe to configuration change notifications. Use after defining and attaching a handler with `OnConfigUpdate()`.	UInt16 SubscribeToConfigurationChanges (string Target)
UnsubscribeFromConfigurationChanges	Unsubscribe from configuration change notifications.	UInt16 UnsubscribeFromConfigurationChanges (string Target)

Manage Polls and Polling Events

Users with administrative privilege can create and manage viewer polls. Use these SDK functions manage subscriptions to polling events, and get poll responses.

Function	Description	Signature
CreatePoll	Create and name a poll, with a prompt and list of options. Available only when current user has "admin" role.	`UInt16 CreatePoll` `(String` PollId, `String` Prompt, `List< String >` Options)
DeletePoll	Delete the named poll and all its data. Available only when current user has "admin" role	`UInt16 DeletePoll` `(String` PollId)
GetPollCallback	Handler signature for response to `GetPoll()` call.	`delegate void GetPollCallback` `(GetPollResponse` Response)
GetPoll	Retrieve poll results once, and pass them to the Callback handler.	`UInt16 GetPoll` `(String` PollId, `GetPollCallback` Callback)
PollUpdateResponseCallback	Handler signature for response to Poll Update. Pass to `OnPollUpdate()` call.	`delegate void PollUpdateResponseCallback` `(PollUpdateResponse` PResp)
OnPollUpdate	Sets callback to handle Poll Update events. You must call to `SubscribeToPoll()` to begin receiving Poll Update events.	`UInt32 OnPollUpdate` `(PollUpdateResponseCallback` Callback)
DetachOnPollUpdate	Detach callback for Poll Update events, using Handle returned from `OnPollUpdate()` call.	`void DetachOnPollUpdate` `(UInt32` Handle)
SubscribeToPoll	Subscribe to a named poll. Before subscribing, use `OnPollUpdate ()` to set the callback that handles polling events.	`UInt16 SubscribeToPoll` `(String` PollId)
UnsubscribeFromPoll	Unsubscribe from the named poll.	`UInt16 UnsubscribeFromPoll` `(String` PollId)

Twitch Bit Transactions

The following SDK functions let you manage Twitch Bit Transactions from extension viewers.

Function	Description	C# Signature
SubscribeToSKU	Subscribe to SKU purchase notifications.	`UInt16 SubscribeToSKU` `(string` SKU)
UnsubscribeFromSKU	Unsubscribe from SKU purchase notifications.	`UInt16 UnsubscribeFromSKU` `(string` SKU)
SubscribeToAllPurchases	Subscribe to all Twitch Bit Purchase notifications.	`UInt16 SubscribeToAllPurchases ()`
UnsubscribeFromAllPurchases	Unsubscribe from all Twitch Bit Purchase notifications.	`UInt16 UnsubscribeFromAllPurchases ()`
TransactionCallback	Handler signature for response to purchase events. Pass to `OnTransaction()` call.	`delegate void TransactionCallback` `(Transaction` Purchase)
OnTransaction	Sets callback for Twitch Bit Purchasing events. You must subscribe by calling to `SubscribeToSKU()` or `SubscribeToAllPurchases()` to begin receiving purchase events.	`UInt32 OnTransaction` `(TransactionCallback` Callback)
DetachOnTransaction	Detach callback for Twitch Bit Purchases using Handle returned from `OnTransaction()` call.	`void DetachOnTransaction` ` (UInt32 Handle)
GetOutstandingTransactionsCallback	Handler signature for response to `GetOutstandingTransactions()` calls.	`delegate void GetOutstandingTransactionsCallback` `(OutstandingTransactions` Transactions)
GetOutstandingTransactions	Get all outstanding transactions that need validation.	`UInt16 GetOutstandingTransactions` `(String` SKU, `GetOutstandingTransactionsCallback` Callback)
RefundTransactionByID	Refund given transaction for user.	`UInt16 RefundTransactionByID` `(String` TxId, `String` UserId)
RefundTransactionBySKU	Refund given transaction for user.	`UInt16 RefundTransactionBySKU` `(String` SKU, `String` UserId)
ValidateTransaction	Validate given transaction.	`UInt16 ValidateTransaction` `(String` TxId, `String` Details)