Add initial grpc server implementation

Still need to use a factory to get the correct vehicle, based on environment variables.

SwiftyCar/Package.resolved

@@ -6,8 +6,8 @@
         "repositoryURL": "https://github.com/grpc/grpc-swift.git",
         "state": {
           "branch": null,
-          "revision": "373ffd54c1c1a319d0ddac9476d13be9023584bb",
-          "version": "1.0.0-alpha.11"
+          "revision": "b83ee1ee2caa0660eb02444977b9b6e353c2adbf",
+          "version": "1.0.0-alpha.12"
         }
       },
       {

SwiftyCar/Package.swift

@@ -1,4 +1,4 @@
-// swift-tools-version:5.2
+// swift-tools-version:5.1
 // The swift-tools-version declares the minimum version of Swift required to build this package.
 
 import PackageDescription
@@ -11,7 +11,7 @@ let package = Package(
     dependencies: [
         // Dependencies declare other packages that this package depends on.
         // .package(url: /* package url */, from: "1.0.0"),
-        .package(url: "https://github.com/grpc/grpc-swift.git", from: "1.0.0-alpha.11"),
+        .package(url: "https://github.com/grpc/grpc-swift.git", from: "1.0.0-alpha.12"),
         .package(url: "https://github.com/uraimo/SwiftyGPIO.git", from: "1.0.0"),
     ],
     targets: [

SwiftyCar/Sources/SwiftyCar/main.swift

@@ -5,7 +5,47 @@
 //  Created by Michael Pivato on 8/5/20.
 //
 
-// Entry-Point to the Swift Car Controller
-var text = "Hello World!"
-print(text)
+import NIO
+import SwiftyGPIO
+import GRPC
 
+func doServer() throws {
+    // Copied from examples
+    // Create an event loop group for the server to run on.
+    let group = MultiThreadedEventLoopGroup(numberOfThreads: System.coreCount)
+    defer {
+      try! group.syncShutdownGracefully()
+    }
+    
+    let pwms = SwiftyGPIO.hardwarePWMs(for:.RaspberryPi3)!
+    
+    // Read the feature database.
+    let vehicle = try RPiVehicle2D(withThrottlePin: Servo(forPin: (pwms[0]?[.P18])!)!, withSteeringPin:Servo(forPin: (pwms[1]?[.P19])!)!)
+    // Create a provider using the features we read.
+    let provider = MotorProvider(vehicle: vehicle)
+
+    // Start the server and print its address once it has started.
+    let server = Server.insecure(group: group)
+      .withServiceProviders([provider])
+      .bind(host: "localhost", port: 0)
+
+    server.map {
+      $0.channel.localAddress
+    }.whenSuccess { address in
+      print("server started on port \(address!.port!)")
+    }
+
+    // Wait on the server's `onClose` future to stop the program from exiting.
+    _ = try server.flatMap {
+      $0.onClose
+    }.wait()
+}
+
+// Entry-Point to the Swift Car Controller
+print("Starting Server")
+do{
+try doServer()
+}
+catch{
+    print("Server failed")
+}