Escl: Change device ID to be just the UUID

NAPS2.Escl.Tests/ClientServerTests.cs

@@ -13,6 +13,7 @@ public class ClientServerTests
     {
         var job = Substitute.For<IEsclScanJob>();
         using var server = new EsclServer();
+        var uuid = Guid.NewGuid().ToString("D");
         var deviceConfig = new EsclDeviceConfig
         {
             Capabilities = new EsclCapabilities
@@ -20,7 +21,7 @@ public class ClientServerTests
                 Version = "2.0",
                 MakeAndModel = "HP Blah",
                 SerialNumber = "123abc",
-                Uuid = Guid.NewGuid().ToString("D")
+                Uuid = uuid
             },
             CreateJob = _ => job
         };
@@ -34,7 +35,8 @@ public class ClientServerTests
             RemoteEndpoint = IPAddress.IPv6Loopback,
             Port = deviceConfig.Port,
             RootUrl = "eSCL",
-            Tls = false
+            Tls = false,
+            Uuid = uuid
         });
         var caps = await client.GetCapabilities();
         Assert.Equal("2.0", caps.Version);

NAPS2.Escl.Usb/EsclUsbContext.cs

@@ -53,7 +53,8 @@ public class EsclUsbContext : IDisposable
             RemoteEndpoint = IPAddress.Loopback,
             Port = port,
             RootUrl = "eSCL",
-            Tls = false
+            Tls = false,
+            Uuid = Guid.Empty.ToString("D")
         });
         Task.Run(ProxyLoop);
     }

NAPS2.Escl/Client/EsclService.cs

@@ -43,7 +43,7 @@ public class EsclService
     /// <summary>
     /// A unique identifier for the physical scanner device.
     /// </summary>
-    public string? Uuid { get; init; }
+    public required string Uuid { get; init; }
 
     /// <summary>
     /// The make and model of the scanner.

NAPS2.Escl/Client/EsclServiceLocator.cs

@@ -115,9 +115,10 @@ public class EsclServiceLocator : IDisposable
                 }
             }
         }
-        if ((ipv4 == null && ipv6 == null) || port == -1 || host == null)
+        string? uuid = Get(props, "uuid");
+        if ((ipv4 == null && ipv6 == null) || port == -1 || host == null || uuid == null)
         {
-            throw new ArgumentException();
+            throw new ArgumentException("Missing host/IP/port/uuid");
         }
 
         return new EsclService
@@ -128,6 +129,7 @@ public class EsclServiceLocator : IDisposable
             RemoteEndpoint = args.RemoteEndPoint.Address,
             Port = port,
             Tls = isTls,
+            Uuid = uuid,
             ScannerName = props["ty"],
             RootUrl = props["rs"],
             TxtVersion = Get(props, "txtvers"),
@@ -136,7 +138,6 @@ public class EsclServiceLocator : IDisposable
             Thumbnail = Get(props, "representation"),
             Note = Get(props, "note"),
             MimeTypes = Get(props, "pdl")?.Split(','),
-            Uuid = Get(props, "uuid"),
             ColorOptions = Get(props, "cs")?.Split(','),
             SourceOptions = Get(props, "is"),
             DuplexSupported = Get(props, "duplex")?.ToUpperInvariant() == "T"

NAPS2.Sdk.Tests/Remoting/ScanServerIntegrationTests.cs

@@ -38,10 +38,8 @@ public class ScanServerIntegrationTests : ContextualTests
 
         // Set up a client ScanController for scanning through EsclScanDriver -> network -> ScanServer
         _client = new ScanController(ScanningContext);
-        // This device won't match exactly the real device from GetDeviceList but it includes the UUID which is enough
-        // for EsclScanDriver to correctly identify the server for scanning.
         var uuid = new ScanServerDevice { Device = serverDevice, Name = displayName }.GetUuid(_server.InstanceId);
-        _clientDevice = new ScanDevice(Driver.Escl, $"|{uuid}", displayName);
+        _clientDevice = new ScanDevice(Driver.Escl, uuid, displayName);
     }
 
     public override void Dispose()
@@ -54,9 +52,9 @@ public class ScanServerIntegrationTests : ContextualTests
     public async Task FindDevice()
     {
         var devices = await _client.GetDeviceList(Driver.Escl);
-        // The device name is suffixed with the IP so we just check the prefix matches (and vice versa for ID)
+        // The device name is suffixed with the IP so we just check the prefix matches
         Assert.Contains(devices,
-            device => device.Name.StartsWith(_clientDevice.Name) && device.ID.EndsWith(_clientDevice.ID));
+            device => device.Name.StartsWith(_clientDevice.Name) && device.ID == _clientDevice.ID);
     }
 
     [Fact]

NAPS2.Sdk/Scan/Internal/Escl/EsclScanDriver.cs

@@ -21,10 +21,16 @@ internal class EsclScanDriver : IScanDriver
     public static string GetUuid(ScanDevice device)
     {
         var parts = device.ID.Split('|');
+        if (parts.Length == 1)
+        {
+            // Current IDs are just the UUID
+            return parts[0];
+        }
         if (parts.Length != 2)
         {
             throw new ArgumentException("Invalid ESCL device ID");
         }
+        // Old IDs have both the IP and UUID separated by "|"
         return parts[1];
     }
 
@@ -40,14 +46,15 @@ internal class EsclScanDriver : IScanDriver
         var localIPsTask = options.ExcludeLocalIPs ? LocalIPsHelper.Get() : null;
         using var locator = new EsclServiceLocator(service =>
         {
-            // Store both the IP and UUID so we can preferentially find by the IP, but also fall back to looking for
-            // the UUID in case the IP changed
             var ip = service.IpV4 ?? service.IpV6!;
             if (options.ExcludeLocalIPs && localIPsTask!.Result.Contains(ip.ToString()))
             {
                 return;
             }
-            var id = $"{ip}|{service.Uuid}";
+            // TODO: When we implement scanner capabilities, store all the connection information in there so we can
+            // try and connect directly before querying for a potentially-updated-IP (and then back-propagate the new
+            // connection info).
+            var id = service.Uuid;
             var name = string.IsNullOrEmpty(service.ScannerName)
                 ? $"{ip}"
                 : $"{service.ScannerName} ({ip})";