feat: Async DTMF listener

Author: SMadani

CHANGELOG.md

@@ -4,11 +4,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
-## [1.1.0] - 2024-11-??
+## [1.1.0] - 2024-11-05
 
 ### Added
-- Custom template management for Verify API
 - Pricing API
+- Custom template management for Verify API
+- Asynchronous DTMF event listener endpoints in Voice API
 
 ## [1.0.0] - 2024-10-25
 First stable GA release

src/main/kotlin/com/vonage/client/kt/Voice.kt

@@ -99,6 +99,23 @@ class Voice internal constructor(private val client: VoiceClient) {
          */
         fun sendDtmf(digits: String): DtmfResponse = client.sendDtmf(id, digits)
 
+        /**
+         * Subscribe to real-time DTMF key presses on the call, where the input mode is [InputMode.ASYNCHRONOUS].
+         *
+         * @param eventUrl The publicly accessible URL to send DTMF events to,
+         * which can be deserialised using [EventWebhook.fromJson].
+         *
+         * @since 1.1.0
+         */
+        fun subscribeToDtmfEvents(eventUrl: String): Unit = client.addDtmfListener(id, eventUrl)
+
+        /**
+         * Stop asynchronous DTMF events being sent to the URL configured in [subscribeToDtmfEvents].
+         *
+         * @since 1.1.0
+         */
+        fun stopAsyncDtmfEvents(): Unit = client.removeDtmfListener(id)
+
         /**
          * Play an audio file to the call.
          *

src/test/kotlin/com/vonage/client/kt/VoiceTest.kt

@@ -329,6 +329,20 @@ class VoiceTest : AbstractTest() {
         assertEquals(callIdStr, response.uuid)
     }
 
+    @Test
+    fun `subscribe to real-time DTMF events`() {
+        mockPut(expectedUrl = "$callUrl/input/dtmf", status = 200,
+            expectedRequestParams = mapOf("event_url" to listOf(eventUrl))
+        )
+        existingCall.subscribeToDtmfEvents(eventUrl)
+    }
+
+    @Test
+    fun `stop receiving real-time DTMF events`() {
+        mockDelete(expectedUrl = "$callUrl/input/dtmf")
+        existingCall.stopAsyncDtmfEvents()
+    }
+
     @Test
     fun `stream audio into call`() {
         val loop = 3