Multiple Databases with C# and ASP.Net Scopes

Databases.cs

using System.Collections.Concurrent;
using System.Data;
using Microsoft.Data.SqlClient;

public class DatabaseConnections : IDisposable {
  public IDbConnection? FirstConnection { get { return getSqlConnection("First"); } }
  public IDbConnection? SecondConnection { get { return getSqlConnection("Second"); } }

  private IConfiguration config {get;set;}
  private ConcurrentDictionary<string, IDbConnection> Connections = new ConcurrentDictionary<string, IDbConnection>();


  public DatabaseConnections(IConfiguration config) {
    this.config = config;
  }

  ~DatabaseConnections() {
    this.Dispose();
  }

  private IDbConnection? getSqlConnection(string name) {
    IDbConnection? cn;
    if (this.Connections.TryGetValue(name, out cn)) {
      return cn;
    }

    var cs = this.config.GetConnectionString(name);
    if (string.IsNullOrWhiteSpace(cs)) {
      return null;
    }
    try {
      var csb = new SqlConnectionStringBuilder(cs);
      
      // TODO: configure for allowed cert chain
      csb.TrustServerCertificate = true;

      cn = new SqlConnection(csb.ConnectionString);
      this.Connections.TryAdd(name, cn);
      return cn;
    } catch(Exception) {
      return null;
    }
  }

  public void Dispose()
  {
    var keys = this.Connections.Keys;
    foreach (var key in keys) {
      IDbConnection? cn;
      if (Connections.Remove(key, out cn)) {
        cn.Dispose();
      }
    }
  }
}

public static class DatabaseConnectionsExtensions {
  public static void AddDatabaseConnections(this IServiceCollection services)
  {
    services.AddScoped(o => {
      var config = o.GetService<IConfiguration>();
      if (config is null) throw new ApplicationException("Missing configuration.");
      return new DatabaseConnections(config);
    });
  }
}