network_data_transfer #

A network data transfer package using dart.

This package assumes that the devices are already on the same network.

See the documentation here, or here for more information on available classes and methods.

Usage #

See test directory on how to start a Client and Server as well as sending files and messages.

Sample client_test.dart for working with Client:

import 'package:network_data_transfer/host.dart';
import 'package:english_words/english_words.dart';

Iterable<Device> devices;
Client client;

void main() async{
  client = Client(
    ipVersion: IPVersion.v4,
    name: "Client", // Optional friendly name of the Client host
    deviceDiscoveryListener: MyDiscoveryListener(),
    connectionListener: MyConnectionListener(),
  );

  // Wait for the Client to completely initialize
  if(!await client.ready){
    print("Could not start on Client");
    return;
  }
  print("Client is ready. IP: ${client.ipAddress}");

  // Start discovering devices
  print("Discovering hosts...");
  client.discoverHosts();
}

// Create listener for receiving advertisements and discovery alerts from the Server
class MyDiscoveryListener implements DeviceDiscoveryListener{
  @override
  onDiscovery(Device newDevice, Iterable<Device> allDevices) {
    print("Server Discovery Alert: $newDevice");
    devices = allDevices;

    // Connect to Server
    client.connectTo(newDevice);
  }
  @override
  onClose(bool isError, Object error, StackTrace stackTrace){
    print("Discovery multicast socket closed");
  }

  @override
  void onAdvertisement(Device device, Packet packet) {
    print("Received ${packet.asString()} in onAdvertisement from Server.");
  }
}

class MyConnectionListener implements ConnectionListener{
  @override
  void onConnected(Device device) {
    print("Server Connected: $device");
  }

  @override
  void onDisconnected(Device device, bool isError, Object error, StackTrace stackTrace) {
    print("Server Disconnected: $device");
  }

  @override
  void onMessage(Packet packet, Device device) {
    print("Message Received from Server $device: ${packet.asString()}");
    // Send message back to this client
    Future.delayed(Duration(seconds: 1)).then((_) =>
        client.send(Packet.from(WordPair.random().asPascalCase), device,
            ignoreIfNotConnected: true)
    );
  }
}

Sample server_test.dart for working with a Server:

import 'dart:io';

import 'package:network_data_transfer/host.dart';
import 'package:english_words/english_words.dart';

Iterable<Device> devices;
Server server;

void main() async{
  server = Server(
    ipVersion: IPVersion.v4,
    name: "Server", // Optional friendly name of the Server host
    deviceDiscoveryListener: MyDiscoveryListener(),
    connectionListener: MyConnectionListener(),
    listenOn: useFirstFoundIP // Optional. Do not provide if you want to listen on all ip addresses
  );

  // Wait for the Server to completely initialize
  if(!await server.ready){
    print("Could not connect on Server");
    return;
  }
  print("Server is ready at ${server.ipAddress}:${server.port}");
}

// Use the first IP address we find for the first interface. 
// This is optional but can be used to choose the IP address for the correct interface
Future<String> useFirstFoundIP(Future<Iterable<Map<NetworkInterface, Iterable<InternetAddress>>>> interfaceAddresses) async{
  Iterable<Map<NetworkInterface, Iterable<InternetAddress>>> addressList = await interfaceAddresses;
  return addressList.first.values.first.first.address;
}

// Create listener for receiving discovery alerts from clients
class MyDiscoveryListener implements DeviceDiscoveryListener{
  @override
  onDiscovery(Device newDevice, Iterable<Device> allDevices) {
    print("New Client Device Alert: $newDevice");
    devices = allDevices;
  }

  @override
  onClose(bool isError, Object error, StackTrace stackTrace){
    print("Discovery multicast socket closed");
  }

  @override
  void onAdvertisement(Device device, Packet packet) {
    // Will never be used on the Server
  }
}

// Create a listener to listen for connection and disconnection as well as
// when messages arrive 
class MyConnectionListener implements ConnectionListener{
  @override
  void onConnected(Device device) {
    print("Device Connected to Server: $device");
    // Send a handshake to begin conversation
    server.send(Packet.from(WordPair.random().asPascalCase), device);
  }

  @override
  void onDisconnected(Device device, bool isError, Object error, StackTrace stackTrace) {
    print("Device Disconnected from Server: $device");
  }

  @override
  void onMessage(Packet packet, Device device) {
    print("Message Received from Client $device: ${packet.asString()}");
    Future.delayed(Duration(seconds: 1)).then((_) =>
        server.send(Packet.from(WordPair.random().asPascalCase), device,
            ignoreIfNotConnected: true)
    );
  }
}