Firebaseを使ってAndroidアプリで電話をかけたり受けたりする

exports.answer = functions.https.onRequest((request, response) => {
  //use the `to` query parameter that Nexmo gives us to make a call.
  //if `to` is null, then we are receiving a call.
  var to = request.query.to
  var from = request.query.from

  var ncco = [];

  if (to) {
    ncco.push(
      {
        action: "talk",
        text: "Thank you for calling, you are now being connected."
      },
      {
        "action": "connect",
        "from": functions.config().nexmo.from_number,
        "endpoint": [
          {
            "type": "phone",
            "number": `${to}`
          }
        ]
      }
    )
  } else {
    ncco.push(
      {
        action: "talk",
        text: "You are being connected to the Customer."
      },
      {
        "action": "connect",
        "from": from,
        "endpoint": [
          {
            "type": "app",
            "user": "Customer"
          }
        ]
  
      })
  }
  response.json(ncco);
});

"dependencies": {
    "firebase-admin": "~5.12.1",
    "firebase-functions": "^1.0.3",
    "nexmo": "^2.3.2"
  }

exports.jwt = functions.https.onRequest((request, response) => {
    response.json({
      user_jwt: Nexmo.generateJwt("private.key", {
        application_id: functions.config().nexmo.application_id,
        sub: "Customer",
        exp: new Date().getTime() + 86400,
        acl: adminAcl
      })
    });
});

npm install @vonage/cli -g

vonage config:set --apiKey=VONAGE_API_KEY --apiSecret=VONAGE_API_SECRET

# Ensure you're in the firebase-functions-nexmo-in-app-calling/ directory we created at the beginning of this tutorial
vonage apps:create 
✔ Application Name … ruling_narwhal
✔ Select App Capabilities › Voice
✔ Create voice webhooks? … yes
✔ Answer Webhook - URL … https://your-project-name.cloudfunctions.net/answer
✔ Answer Webhook - Method › POST
✔ Event Webhook - URL … https://your-project-name.cloudfunctions.net/event
✔ Event Webhook - Method › POST
✔ Allow use of data for AI training? Read data collection disclosure - https://help.nexmo.com/hc/en-us/articles/4401914566036 … no
Creating Application... done
Application Name: ruling_narwhal

vonage apps:link --number=VONAGE_NUMBER APP_ID

dependencies {
  implementation 'com.nexmo:stitch:1.8.0'
  implementation 'com.squareup.retrofit2:retrofit:2.4.0'
  implementation "com.squareup.retrofit2:converter-moshi:2.4.0"
}

//FirebaseFunctionService.kt
interface FirebaseFunctionService {
    @GET("jwt")
    fun getJWT(): Call<UserJWT>
}


//RetrofitClient.kt
var retrofitClient = Retrofit.Builder()
        .baseUrl("https://your-project-name.cloudfunctions.net/")
        .addConverterFactory(MoshiConverterFactory.create())
        .build()

var retrofitService = retrofitClient.create<FirebaseFunctionService>(FirebaseFunctionService::class.java)

class LoginActivity : BaseActivity(), RequestHandler<User>, Callback<UserJWT> {
    override fun onCreate(savedInstanceState: Bundle?) {
        ...
        loginBtn.setOnClickListener {
            login()
        }
    }

    private fun login() {
        showProgress(true)
        retrofitService.getJWT().enqueue(this)
    }

    //Successfully retrieved a JWT from the Firebase Function endpoint
    override fun onResponse(call: Call<UserJWT>?, response: Response<UserJWT>?) {
        val jwt = response?.body()?.user_jwt
        client.login(jwt, this)
    }

    //User successfully logged in with the Nexmo Stitch SDK
    override fun onSuccess(result: User?) {
        goToCallActivity()
    }

}

class CallActivity : BaseActivity(), RequestHandler<Call> {
    private var currentCall: Call? = null
    private lateinit var client: ConversationClient

    override fun onCreate(savedInstanceState: Bundle?) {
        ...
        client = Stitch.getInstance(this).conversationClient

        attachIncomingCallListener()
        callControlBtn.setOnClickListener { callPhone() }
    }

    private fun attachIncomingCallListener() {
        //Listen for incoming calls
        client.callEvent().add({ incomingCall ->
            logAndShow("answering Call")
            //Answer an incoming call
            incomingCall.answer(object : RequestHandler<Void> {
                override fun onError(apiError: NexmoAPIError) {
                    logAndShow("Error answer: " + apiError.message)
                }

                override fun onSuccess(result: Void) {
                    currentCall = incomingCall
                    attachCallStateListener(incomingCall)
                    showHangupButton()
                }
            })
        })
    }

    private fun attachCallStateListener(incomingCall: Call) {
        //Listen for incoming member events in a call
        val callEventListener = ResultListener<CallEvent> { message ->
            logAndShow("callEvent : state: " + message.state + " .content:" + message.toString())
        }
        incomingCall.event().add(callEventListener)
    }


    private fun callPhone() {
        val phoneNumber = phoneNumberInput.text.toString()

        client.callPhone(phoneNumber, object : RequestHandler<Call> {
            override fun onError(apiError: NexmoAPIError) {
                logAndShow("Cannot initiate call: " + apiError.message)
            }

            override fun onSuccess(result: Call) {
                currentCall = result
                showHangupButton()

                when (result.callState) {
                    Call.CALL_STATE.STARTED -> logAndShow("Started")
                    Call.CALL_STATE.RINGING -> logAndShow("Ringing")
                    Call.CALL_STATE.ANSWERED -> logAndShow("Answered")
                    else -> logAndShow("Error attaching call listener")
                }

            }
        })
    }

}

[  
   {  
      "action":"talk",
      "text":"You are being connected to the Customer."
   },
   {  
      "action":"connect",
      "endpoint":[  
         {  
            "type":"app",
            "user":"Customer"
         }
      ]
   }
]

client.callPhone("14155550100", callback)

[  
   {  
      "action":"talk",
      "text":"Thank you for calling, you are now being connected."
   },
   {  
      "action":"connect",
      "from":"12013753230",
      "endpoint":[  
         {  
            "type":"phone",
            "number":"14155550100"
         }
      ]
   }
]