Merge pull request #67 from sharpbrick/issue-65-simpler-discovery

Make DiscoveryAsync more user friendly

#65 non-breaking

Author: tthiery

README.md

@@ -31,22 +31,23 @@ var serviceProvider = new ServiceCollection()
 
 var host = serviceProvider.GetService<PoweredUpHost>();
 
+var hub = await host.DiscoverAsync<TechnicMediumHub>(); // starting version 2.1
+await hub.ConnectAsync();
+````
+
+## Discovering Hubs for UI
+````csharp
+var host = serviceProvider.GetService<PoweredUpHost>();
+
 var cts = new CancellationTokenSource();
 host.Discover(async hub =>
 {
-    await hub.ConnectAsync();
-
-    Console.WriteLine(hub.AdvertisingName);
-    Console.WriteLine(hub.SystemType.ToString());
+    await hub.ConnectAsync(); // to get some more properties from it
 
-    cts.Cancel();
-    Console.WriteLine("Press RETURN to continue");
+    // show in UI
 }, cts.Token);
 
-Console.WriteLine("Press RETURN to cancel Scanning");
-Console.ReadLine();
-
-cts.Cancel();
+// Cancel Button => cts.Cancel();
 ````
 
 ## Sending Commands to Ports and Devices of a Hub
@@ -56,7 +57,7 @@ See source code in `examples/SharpBrick.PoweredUp.Examples` for more examples.
 ````csharp
 // do hub discovery before
 
-using (var technicMediumHub = host.FindByType<TechnicMediumHub>())
+using (var technicMediumHub = hub as TechnicMediumHub)
 {
     // optionally verify if everything is wired up correctly (v2.0 onwards)
     await technicMediumHub.VerifyDeploymentModelAsync(modelBuilder => modelBuilder

examples/SharpBrick.PoweredUp.Examples/BaseExample.cs

@@ -24,13 +24,13 @@ public virtual void Configure(IServiceCollection serviceCollection)
                 .AddPoweredUp();
         }
 
-        public void InitHostAndDiscover(bool enableTrace)
+        public async Task InitHostAndDiscoverAsync(bool enableTrace)
         {
             InitHost(enableTrace);
-            Discover(enableTrace);
+            await DiscoverAsync(enableTrace);
         }
 
-        public virtual void Discover(bool enableTrace)
+        public virtual Task DiscoverAsync(bool enableTrace)
         {
             var logger = serviceProvider.GetService<ILoggerFactory>().CreateLogger("Main");
 
@@ -67,6 +67,8 @@ public virtual void Discover(bool enableTrace)
             cts.Cancel();
 
             selectedHub = result;
+
+            return Task.CompletedTask;
         }
 
         public void InitHost(bool enableTrace)

examples/SharpBrick.PoweredUp.Examples/ExampleBluetoothByKnownAddress.cs

@@ -10,13 +10,13 @@ public class ExampleBluetoothByKnownAddress : BaseExample
         public TechnicMediumHub DirectlyConnectedHub { get; private set; }
 
         // device needs to be switched on!
-        public override void Discover(bool enableTrace)
+        public override async Task DiscoverAsync(bool enableTrace)
         {
             var hub = host.Create<TechnicMediumHub>(ChangeMe_BluetoothAddress);
 
             selectedHub = DirectlyConnectedHub = hub;
 
-            hub.ConnectAsync().Wait();
+            await hub.ConnectAsync();
         }
 
         public override async Task ExecuteAsync()

examples/SharpBrick.PoweredUp.Examples/ExampleDiscoverByType.cs

@@ -0,0 +1,41 @@
+using System;
+using System.Threading.Tasks;
+using SharpBrick.PoweredUp;
+
+namespace Example
+{
+    public class ExampleDiscoverByType : BaseExample
+    {
+        public TechnicMediumHub DirectlyConnectedHub { get; private set; }
+
+        // device needs to be switched on!
+        public override async Task DiscoverAsync(bool enableTrace)
+        {
+            var hub = await host.DiscoverAsync<TechnicMediumHub>();
+
+            selectedHub = DirectlyConnectedHub = hub;
+
+            await hub.ConnectAsync();
+        }
+
+        public override async Task ExecuteAsync()
+        {
+            using (var technicMediumHub = DirectlyConnectedHub)
+            {
+                await technicMediumHub.RgbLight.SetRgbColorsAsync(0xff, 0x00, 0x00);
+
+                await Task.Delay(2000);
+
+                await technicMediumHub.RgbLight.SetRgbColorsAsync(0x00, 0xff, 0x00);
+
+                await Task.Delay(2000);
+
+                await technicMediumHub.RgbLight.SetRgbColorsAsync(0xff, 0xff, 0x00);
+
+                await Task.Delay(2000);
+
+                await technicMediumHub.SwitchOffAsync();
+            }
+        }
+    }
+}

examples/SharpBrick.PoweredUp.Examples/Program.cs

@@ -29,9 +29,10 @@ static async Task Main(string[] args)
             //example = new Example.ExampleBluetoothByKnownAddress();
             //example = new Example.ExampleBluetoothByName();
             //example = new Example.ExampleSetHubProperty();
-            example = new Example.ExampleHubPropertyObserving();
+            //example = new Example.ExampleHubPropertyObserving();
+            example = new Example.ExampleDiscoverByType();
 
-            example.InitHostAndDiscover(enableTrace);
+            await example.InitHostAndDiscoverAsync(enableTrace);
 
             if (example.selectedHub != null)
             {

src/SharpBrick.PoweredUp/PoweredUpHost.cs

@@ -53,11 +53,34 @@ public void Discover(Func<Hub, Task> onDiscovery, CancellationToken token = defa
 
                     _hubs.Add((deviceInfo, hub));
 
+                    _logger.LogInformation($"Discovered log of type {hub.GetType().Name} with name '{deviceInfo.Name}' on Bluetooth Address '{deviceInfo.BluetoothAddress}'");
+
                     onDiscovery(hub).Wait();
                 }
             }, token);
         }
 
+        public async Task<THub> DiscoverAsync<THub>(CancellationToken token = default)
+        {
+            var tcs = new TaskCompletionSource<THub>();
+
+            Discover(hub =>
+            {
+                if (hub is THub tHub)
+                {
+                    tcs.SetResult(tHub);
+                }
+
+                return Task.CompletedTask;
+            }, token);
+
+            var hub = await tcs.Task;
+
+            _logger.LogInformation($"End DiscoveryAsync for {typeof(THub).Name}");
+
+            return hub;
+        }
+
         public THub Create<THub>(ulong bluetoothAddress) where THub : Hub
         {
             var hub = _hubFactory.Create<THub>();