1 files changed, 154 insertions, 0 deletions
diff --git a/Software/Visual_Studio/Web/Tango.MachineService/Telemetry/TelemetryDeviceRegistrationManager.cs b/Software/Visual_Studio/Web/Tango.MachineService/Telemetry/TelemetryDeviceRegistrationManager.cs
new file mode 100644
index 000000000..0bf8d2bdc
--- /dev/null
+++ b/Software/Visual_Studio/Web/Tango.MachineService/Telemetry/TelemetryDeviceRegistrationManager.cs
@@ -0,0 +1,154 @@
+using System;
+using Microsoft.WindowsAzure.Storage;
+using Microsoft.WindowsAzure.Storage.Table; // same SDK as your sample
+using Microsoft.Azure.Devices;              // Install-Package Microsoft.Azure.Devices
+using Microsoft.Azure.Devices.Common.Exceptions;
+
+namespace Tango.MachineService.Telemetry
+{
+    internal sealed class TelemetryDeviceRegistrationEntity : TableEntity
+    {
+        public TelemetryDeviceRegistrationEntity() { }
+
+        public TelemetryDeviceRegistrationEntity(string machineGuid, string serialNumber)
+        {
+            PartitionKey = machineGuid;
+            RowKey = SanitizeRowKey(serialNumber);
+        }
+
+        public String Environment { get; set; }
+        public string SerialNumber { get; set; }
+        public string DeviceId { get; set; }
+        public string ConnectionString { get; set; }
+        public DateTime CreatedUtc { get; set; }
+        public DateTime UpdatedUtc { get; set; }
+
+        internal static string SanitizeRowKey(string value) =>
+            (value ?? string.Empty)
+            .Replace("/", "_").Replace("\\", "_")
+            .Replace("#", "_").Replace("?", "_");
+    }
+
+    /// <summary>
+    /// Creates/gets IoT Hub device identities and caches the per-device connection string
+    /// in Azure Table Storage ("TelemetryDeviceRegistrations").
+    /// PartitionKey = MachineGuid, RowKey = SerialNumber (sanitized).
+    /// </summary>
+    public sealed class TelemetryDeviceRegistrationManager
+    {
+        private readonly string _iotHubServiceConnectionString;
+        private readonly string _iotHubHostName;
+        private readonly CloudTable _table;
+        private readonly object _locker = new object();
+
+        public TelemetryDeviceRegistrationManager(
+            string storageAccountConnectionString,
+            string iotHubServiceConnectionString,
+            string tableName = "TelemetryDeviceRegistrations")
+        {
+            if (string.IsNullOrWhiteSpace(storageAccountConnectionString))
+                throw new ArgumentNullException(nameof(storageAccountConnectionString));
+            if (string.IsNullOrWhiteSpace(iotHubServiceConnectionString))
+                throw new ArgumentNullException(nameof(iotHubServiceConnectionString));
+            if (string.IsNullOrWhiteSpace(tableName))
+                throw new ArgumentNullException(nameof(tableName));
+
+            _iotHubServiceConnectionString = iotHubServiceConnectionString;
+            _iotHubHostName = ExtractHostName(iotHubServiceConnectionString);
+
+            var storageAccount = CloudStorageAccount.Parse(storageAccountConnectionString);
+            var tableClient = storageAccount.CreateCloudTableClient();
+            _table = tableClient.GetTableReference(tableName);
+            _table.CreateIfNotExists(); // sync, as in your sample
+        }
+
+        /// <summary>
+        /// Returns the per-device IoT Hub connection string for (machineGuid, serialNumber).
+        /// Creates the IoT Hub device (DeviceId = serialNumber) if needed, persists the connection string,
+        /// then returns the cached value next time.
+        /// </summary>
+        public string GetOrCreateDeviceConnectionString(string machineGuid, string serialNumber)
+        {
+            if (string.IsNullOrWhiteSpace(machineGuid)) throw new ArgumentNullException(nameof(machineGuid));
+            if (string.IsNullOrWhiteSpace(serialNumber)) throw new ArgumentNullException(nameof(serialNumber));
+
+            // 1) Try table cache
+            var cached = TryGetFromTable(machineGuid, serialNumber);
+            if (!string.IsNullOrEmpty(cached))
+                return cached;
+
+            // 2) Create/get in IoT Hub (guard against concurrent callers)
+            lock (_locker)
+            {
+                // double-check after lock
+                cached = TryGetFromTable(machineGuid, serialNumber);
+                if (!string.IsNullOrEmpty(cached))
+                    return cached;
+
+                var registry = RegistryManager.CreateFromConnectionString(_iotHubServiceConnectionString);
+
+                Device device;
+                try
+                {
+                    device = registry.AddDeviceAsync(new Device(serialNumber)).GetAwaiter().GetResult();
+                }
+                catch (DeviceAlreadyExistsException)
+                {
+                    device = registry.GetDeviceAsync(serialNumber).GetAwaiter().GetResult();
+                }
+
+                if (device == null)
+                    throw new InvalidOperationException("Failed to get or create IoT Hub device.");
+
+                var primaryKey = device.Authentication?.SymmetricKey?.PrimaryKey;
+                if (string.IsNullOrEmpty(primaryKey))
+                    throw new InvalidOperationException("Device has no symmetric key.");
+
+                var deviceConnectionString =
+                    $"HostName={_iotHubHostName};DeviceId={serialNumber};SharedAccessKey={primaryKey}";
+
+                UpsertToTable(machineGuid, serialNumber, deviceConnectionString);
+
+                return deviceConnectionString;
+            }
+        }
+
+        // ---- Table helpers (sync) ----
+
+        private string TryGetFromTable(string machineGuid, string serialNumber)
+        {
+            var rowKey = TelemetryDeviceRegistrationEntity.SanitizeRowKey(serialNumber);
+            var retrieve = TableOperation.Retrieve<TelemetryDeviceRegistrationEntity>(machineGuid, rowKey);
+            var result = _table.Execute(retrieve);
+            var entity = result.Result as TelemetryDeviceRegistrationEntity;
+            return entity?.ConnectionString;
+        }
+
+        private void UpsertToTable(string machineGuid, string serialNumber, string connectionString)
+        {
+            var entity = new TelemetryDeviceRegistrationEntity(machineGuid, serialNumber)
+            {
+                SerialNumber = serialNumber,
+                DeviceId = serialNumber,
+                Environment = MachineServiceConfig.DEPLOYMENT_SLOT.ToString(),
+                ConnectionString = connectionString,
+                CreatedUtc = DateTime.UtcNow,
+                UpdatedUtc = DateTime.UtcNow
+            };
+
+            var op = TableOperation.InsertOrReplace(entity);
+            _table.Execute(op);
+        }
+
+        // ---- Utility ----
+
+        private static string ExtractHostName(string iotHubServiceConnectionString)
+        {
+            var parts = iotHubServiceConnectionString.Split(';');
+            foreach (var p in parts)
+                if (p.StartsWith("HostName=", StringComparison.OrdinalIgnoreCase))
+                    return p.Substring("HostName=".Length);
+            throw new ArgumentException("IoT Hub service connection string is missing HostName=…");
+        }
+    }
+}