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Services/SqlServerConnectionFactory.cs

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+using CRAWLER.Configuration;
+using Microsoft.Data.SqlClient;
+using Microsoft.Extensions.Configuration;
+
+namespace CRAWLER.Services;
+
+internal interface IDatabaseConnectionFactory
+{
+    SqlConnection CreateConnection();
+    SqlConnection CreateMasterConnection();
+    DatabaseOptions Options { get; }
+}
+
+internal sealed class SqlServerConnectionFactory : IDatabaseConnectionFactory
+{
+    public SqlServerConnectionFactory(IConfiguration configuration)
+    {
+        Options = configuration.GetSection("Database").Get<DatabaseOptions>()
+                  ?? throw new InvalidOperationException("Раздел Database не найден в appsettings.json.");
+    }
+
+    public DatabaseOptions Options { get; }
+
+    public SqlConnection CreateConnection()
+    {
+        return new SqlConnection(BuildConnectionString(Options.Database));
+    }
+
+    public SqlConnection CreateMasterConnection()
+    {
+        return new SqlConnection(BuildConnectionString("master"));
+    }
+
+    private string BuildConnectionString(string databaseName)
+    {
+        var builder = new SqlConnectionStringBuilder
+        {
+            ApplicationName = Options.ApplicationName,
+            DataSource = Options.Server,
+            InitialCatalog = databaseName,
+            ConnectTimeout = Options.ConnectTimeoutSeconds,
+            Encrypt = Options.Encrypt,
+            IntegratedSecurity = Options.IntegratedSecurity,
+            MultipleActiveResultSets = Options.MultipleActiveResultSets,
+            Pooling = Options.Pooling,
+            MaxPoolSize = Options.MaxPoolSize,
+            MinPoolSize = Options.MinPoolSize,
+            TrustServerCertificate = Options.TrustServerCertificate,
+            ConnectRetryCount = Options.ConnectRetryCount,
+            ConnectRetryInterval = Options.ConnectRetryIntervalSeconds
+        };
+
+        return builder.ConnectionString;
+    }
+}