Call start message

In 1-to-1 calls, a caller and a callee can send a limited size of message to each other during the call setup process. This message is called a call start message.

Supported call type	Supported SDK version
1-to-1 call	All versions

Note

A call start message is functionally equivalent to "Call Init data" available in PlanetKit 5.0.x or lower. Only the name of the feature has been changed since PlanetKit 5.1.

Sending a call start message

A caller and a callee can send a call start message at a different point in time during the call setup process.

Tip

To learn more about the call setup flow, see 1-to-1 call flow.

Caller side

A caller can send a call start message when making a call.

To send a call start message on the caller side, create a PlanetKitCallStartMessage, set the PlanetKitCallStartMessage in a PlanetKitCallParam, and pass the PlanetKitCallParam when calling makeCall().

let callStartMessage = PlanetKitCallStartMessage(data: "Call start message from a caller")
let param = PlanetKitCallParam(myUserId: myUserId, peerUserId: peerUserId, delegate: delegate, accessToken: accessToken)
param.startMessage = callStartMessage

let result = PlanetKitManager.shared.makeCall(param: param)

The message is delivered to the callee in the didVerify callback.

Callee side

A callee can send a call start message when accepting a call.

To send a call start message on the callee side, create a PlanetKitCallStartMessage and pass the PlanetKitCallStartMessage when calling acceptCall().

let callStartMessage = PlanetKitCallStartMessage(data: "Call start message from a callee")

// Get the verified call instance "call" from the result of verifyCall()

call?.acceptCall(startMessage: callStartMessage, useResponderPreparation: false)

The message is delivered to the caller in the didConnect callback.

Size limitation

The maximum size of a call start message is 200 bytes including the null termination character.

Comparison of a call start message and app server data

A call start message and app server data have the following differences:

	Source and destination	Supported call type
Call start message	App client of a caller → App client of a callee App client of a callee → App client of a caller	Only 1-to-1 call
App server data	App client of a caller or participant → App server	1-to-1 call, group call (conference)

Related API

APIs related to the call start message function are as follows.

Classes

• PlanetKitCallStartMessage ^{iOS, macOS}

Methods/Properties

• startMessage ^{iOS, macOS}
• makeCall() ^{iOS, macOS}
• acceptCall() ^{iOS, macOS}

Events

• didVerify ^{iOS, macOS}
• didConnect ^{iOS, macOS}