NfcMqttForwarder

Simple NFC tag message MQTT forwarder based on Paho Android Service. Processes NFC intent and sends its content directly to MQTT Server.

Setup

First things first, simply configure NFC in your app's manifest - follow Google's documentation.
Finally, add the library to your Gradle app script.

Project level Gradle:

   repositories {
        jcenter()
        maven { url "https://jitpack.io" }
   }

App level Gradle:

   dependencies {
         implementation "com.github.smutkiewicz:nfc-mqtt-forwarder:v1.00"
   }

Configure your Activity.

Example in practice:

// You can implement Listener in your Activity
class MainActivity : AppCompatActivity(), OnNfcMqttForwardingResultListener {

    // Initialize Forwarder class
    private val forwarder: NfcMqttForwarder by lazy {
        NfcMqttForwarder(
            application,
            brokerUri = getString(R.string.brokerUri),
            defaultTopic = getString(R.string.defaultTopic),
            isTlsEnabled = true,
            tlsVersion = TLSVersion.TLSv1_2,
            tlsCertificateType = TLSCertificateType.SELF_SIGNED_CERTIFICATE,
            caInputStream = application.assets.open("ca.crt"),
            messageType = MessageType.PAYLOAD_AND_ADDITIONAL_MESSAGE_JSON,
            trimUnwantedBytesFromPayload = true
        )
    }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        // Specify forwarding result listener
        forwarder.onResultListener = this

        // Process in case this intent is NFC intent.
        processNfcOperations(intent)
    }

    override fun onStop() {
        super.onStop()

        // Optional, Forwarder automatically disconnects after processing.
        // See function doc for more.
        forwarder.disconnectFromBroker()
    }

    override fun onNewIntent(intent: Intent) {
        super.onNewIntent(intent)

        // Process in case this intent is NFC intent.
        processNfcOperations(intent)
    }

    private fun processNfcOperations(intent: Intent) {
        Log.d("TAG", "New NFC intent")

        // Check if library supports intent action
        if (NfcMqttForwarder.isIntentsNfcActionSupported(intent)) {
            // Process intent
            forwarder.processNfcIntent(
                intent = intent,
                additionalMessages = mapOf(
                    "attrX" to "nice msg",
                    "attrY" to "some msg"
                )
            )
        }
    }

    override fun onForwardingError(message: String) {
        Log.d(TAG, "Reacting for error in forwarding!")
    }

    override fun onForwardingSuccessful() {
        Log.d(TAG, "Reacting for successfully forwarded msg!")
    }

    companion object {
        val TAG = "MainActivity"
    }
}

Happy coding! :)

smutkiewicz/nfc-mqtt-forwarder

NfcMqttForwarder

Setup