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EXTENSION

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TxClient

extension TxClient

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Methods

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getCall(callId:)

public func getCall(callId: UUID) -> Call?
This function can be used to access any active call tracked by the SDK. A call will be accessible until has ended (transitioned to the DONE state).
  • Parameter callId: The unique identifier of a call.
  • Returns: The Call object that matches the requested callId. Returns nil if no call was found.

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Parameters

NameDescription
callIdThe unique identifier of a call.

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newCall(callerName:callerNumber:destinationNumber:callId:clientState:customHeaders:preferredCodecs:debug:)

public func newCall(callerName: String,
                    callerNumber: String,
                    destinationNumber: String,
                    callId: UUID,
                    clientState: String? = nil,
                    customHeaders:[String:String] = [:],
                    preferredCodecs: [TxCodecCapability]? = nil,
                    debug:Bool = false) throws -> Call
Creates a new Call and starts the call sequence, negotiate the ICE Candidates and sends the invite. This method initiates an outbound call to the specified destination. The call will go through WebRTC negotiation, ICE candidate gathering, and SIP signaling to establish the connection.

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Examples:

// Basic call
let call = try telnyxClient.newCall(
    callerName: "John Doe",
    callerNumber: "1234567890",
    destinationNumber: "18004377950",
    callId: UUID()
)

// Call with preferred audio codecs
let preferredCodecs = [
    TxCodecCapability(mimeType: "audio/opus", clockRate: 48000, channels: 2),
    TxCodecCapability(mimeType: "audio/PCMU", clockRate: 8000, channels: 1)
]
let call = try telnyxClient.newCall(
    callerName: "John Doe",
    callerNumber: "1234567890",
    destinationNumber: "18004377950",
    callId: UUID(),
    preferredCodecs: preferredCodecs
)

// Call with codecs and debug mode enabled
let call = try telnyxClient.newCall(
    callerName: "John Doe",
    callerNumber: "1234567890",
    destinationNumber: "18004377950",
    callId: UUID(),
    customHeaders: ["X-Custom-Header": "Value"],
    preferredCodecs: preferredCodecs,
    debug: true
)
  • Parameters:
    • callerName: The caller name. This will be displayed as the caller name in the remote’s client.
    • callerNumber: The caller Number. The phone number of the current user.
    • destinationNumber: The destination SIP user address (sip:[email protected]) or phone number.
    • callId: The current call UUID.
    • clientState: (optional) Custom state in string format encoded in base64
    • customHeaders: (optional) Custom Headers to be passed over webRTC Messages. Headers should be in the format X-key:Value where X- prefix is required for custom headers. When calling AI Agents, headers with the X- prefix will be mapped to dynamic variables (e.g., X-Account-Number becomes {{account_number}}). Hyphens in header names are converted to underscores in variable names.
    • preferredCodecs: (optional) Array of preferred audio codecs in priority order. The SDK will attempt to use these codecs in the specified order during negotiation. If none of the preferred codecs are available, WebRTC will fall back to its default codec selection. Use getSupportedAudioCodecs() to retrieve available codecs before setting preferences. See the Preferred Audio Codecs Guide for more information.
    • debug: (optional) Enable debug mode for call quality metrics and WebRTC statistics. When enabled, real-time call quality metrics will be available through the call’s onCallQualityChange callback.
  • Throws:
    • sessionId is required if user is not logged in
    • socket connection error if socket is not connected
    • destination number is required to start a call.
  • Returns: The call that has been created

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Parameters

NameDescription
callerNameThe caller name. This will be displayed as the caller name in the remote’s client.
callerNumberThe caller Number. The phone number of the current user.
destinationNumberThe destination SIP user address (sip:[email protected]) or phone number.
callIdThe current call UUID.
clientState(optional) Custom state in string format encoded in base64
customHeaders(optional) Custom Headers to be passed over webRTC Messages. Headers should be in the format X-key:Value where X- prefix is required for custom headers. When calling AI Agents, headers with the X- prefix will be mapped to dynamic variables (e.g., X-Account-Number becomes {{account_number}}). Hyphens in header names are converted to underscores in variable names.
preferredCodecs(optional) Array of preferred audio codecs in priority order. The SDK will attempt to use these codecs in the specified order during negotiation. If none of the preferred codecs are available, WebRTC will fall back to its default codec selection. Use getSupportedAudioCodecs() to retrieve available codecs before setting preferences. See the for more information.
debug(optional) Enable debug mode for call quality metrics and WebRTC statistics. When enabled, real-time call quality metrics will be available through the call’s onCallQualityChange callback.

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getSupportedAudioCodecs()

public func getSupportedAudioCodecs() -> [TxCodecCapability]
Returns the list of supported audio codecs available for use in calls
  • Returns: Array of TxCodecCapability objects representing available audio codecs
This method reuses the shared RTCPeerConnectionFactory instance for efficiency. The codec list is queried from WebRTC’s native capabilities and remains consistent throughout the application lifecycle.

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Example:

let supportedCodecs = telnyxClient.getSupportedAudioCodecs()
for codec in supportedCodecs {
    print("Codec: \(codec.mimeType), Clock Rate: \(codec.clockRate)")
}

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processVoIPNotification(txConfig:serverConfiguration:pushMetaData:)

public func processVoIPNotification(txConfig: TxConfig,
                                    serverConfiguration: TxServerConfiguration,pushMetaData:[String: Any]) throws
Call this function to process a VoIP push notification of an incoming call. This function will be executed when the app was closed and the user executes an action over the VoIP push notification. You will need to
  • Parameters:
    • txConfig: The desired configuration to login to B2B2UA. User credentials must be the same as the
    • serverConfiguration : required to setup from VoIP push notification metadata.
    • pushMetaData : meta data payload from VOIP Push notification (this should be gotten from payload.dictionaryPayload[“metadata”] as? [String: Any])
  • Throws: Error during the connection process

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Parameters

NameDescription
txConfigThe desired configuration to login to B2B2UA. User credentials must be the same as the
serverConfigurationrequired to setup from VoIP push notification metadata.
pushMetaDatameta data payload from VOIP Push notification (this should be gotten from payload.dictionaryPayload[“metadata”] as? [String: Any])

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setEarpiece()

public func setEarpiece()
Select the internal earpiece as the audio output

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setSpeaker()

public func setSpeaker()
Select the speaker as the audio output