Three-Tier Architecture

Architecture Overview

SMAF implements a classic Three-Tier Architecture pattern, separating the application into three distinct logical layers. This architectural approach provides modularity, maintainability, and clear separation of concerns.

Layer 1: Presentation Layer (InapescaWeb)

Project Structure

The presentation layer is organized into functional modules:

Solicitudes
Autorizaciones
Comprobaciones
Pagos

Request Management

Solicitud_Comision.aspx - Travel commission requests
SolicitudPSP.aspx - Special program requests

These pages handle user input for creating and submitting travel allowance requests.

Authorization Workflow

Comision_Aut.aspx - Commission authorization interface

Handles the approval workflow for submitted requests.

Expense Documentation

Comprobacion2017.aspx, Comprobacion2018.aspx - Annual expense forms
ComprobacionAdmin.aspx - Administrative expense tracking
ComprobacionViaticosInternacionales.aspx - International travel expenses
ComprobacionSInXml.aspx - Non-XML voucher submission
Comision_Comprobacion.aspx - Commission expense verification

Payment Processing

Pagos.aspx - General payment processing
PagaViaticos.aspx - Travel allowance disbursement
Pagos_Viaticos.aspx - Travel payment management

Key Components

1. ASPX Pages

ASP.NET Web Forms that render the user interface:

Comision_Aut.aspx.cs (example structure)

public partial class Comision_Aut : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        // Page initialization
    }
    
    protected void btnAutorizar_Click(object sender, EventArgs e)
    {
        // Business layer call
        MngNegocioComision.AutorizarComision(...);
    }
}

2. Utility Classes

The presentation layer includes helper classes:

clsFuncionesGral.cs - General utility functions
clsPdf.cs - PDF generation utilities
clsMenu.cs - Menu structure management
clsTreeview.cs - Hierarchical data display

3. Project References

InapescaWeb.csproj:700-707

<ProjectReference Include="..\InapescaWeb.BRL\InapescaWeb.BRL.csproj">
  <Project>{9E452915-86A4-4499-B7C6-EDB42B6FF5EE}</Project>
  <Name>InapescaWeb.BRL</Name>
</ProjectReference>
<ProjectReference Include="..\InapescaWeb.DAL\InapescaWeb.DAL.csproj">
  <Project>{1211AE21-A6A2-42F4-A400-BCC288C0D4A9}</Project>
  <Name>InapescaWeb.DAL</Name>
</ProjectReference>

The presentation layer references both the Business Logic Layer (BRL) and Data Access Layer (DAL), though best practice would be to only reference BRL.

Layer 2: Business Logic Layer (InapescaWeb.BRL)

Project Structure

The BRL contains business rule classes following a consistent naming pattern: MngNegocio*

<Compile Include="MngNegocioActividades.cs" />
<Compile Include="MngNegocioActualizaDatos.cs" />
<Compile Include="MngNegocioAdscripcion.cs" />
<Compile Include="MngNegocioAnio.cs" />
<Compile Include="MngNegocioComision.cs" />
<Compile Include="MngNegocioComisionDetalle.cs" />
<Compile Include="MngNegocioComisionExtraordinaria.cs" />
<Compile Include="MngNegocioComponente.cs" />
<Compile Include="MngNegocioComprobacion.cs" />
<Compile Include="MngNegocioConfiguraciones.cs" />
<Compile Include="MngNegocioContrato.cs" />
<Compile Include="MngNegocioCuentas.cs" />
<Compile Include="MngNegocioDependencia.cs" />
<Compile Include="MngNegocioDirecciones.cs" />
<Compile Include="MngNegocioEncriptacion.cs" />
<Compile Include="MngNegocioEncriptacionDGAIPP.cs" />

Business Logic Classes

Each class handles a specific business domain:

MngNegocioComision

Commission/travel request business logic

MngNegocioComprobacion

Expense verification and validation

MngNegocioPago

Payment processing and disbursement

MngNegocioMinistracion

Budget allocation logic

MngNegocioProyecto

Project management rules

MngNegocioUsuarios

User management and authentication

MngNegocioViaticos

Travel allowance calculations

MngNegocioPartidas

Budget line item management

MngNegocioReportesViaticos

Travel expense reporting

Example: Commission Business Logic

MngNegocioComision.cs:32-35

public static ComisionProyecto RegresaDatos(string pPeriodo, string pClave, string pDependencia)
{
    return MngDatosComision.RegresaDatos(pPeriodo, pClave, pDependencia);
}

MngNegocioComision.cs:77-80

public static Comision DetalleComision_Pagos(string psFolio, string psDep, 
                                              string psComisionado = "", 
                                              bool psUsuarioPagador = false)
{
    return MngDatosComision.DetalleComision_Pagos(psFolio, psDep, 
                                                    psComisionado, psUsuarioPagador);
}

Layer Dependencies

InapescaWeb.BRL.csproj:96-104

<ProjectReference Include="..\InapescaWeb.DAL\InapescaWeb.DAL.csproj">
  <Project>{1211AE21-A6A2-42F4-A400-BCC288C0D4A9}</Project>
  <Name>InapescaWeb.DAL</Name>
</ProjectReference>
<ProjectReference Include="..\InapescaWeb.Entidades\InapescaWeb.Entidades.csproj">
  <Project>{6B711C7C-3272-43FC-BB0C-A99E644DF90B}</Project>
  <Name>InapescaWeb.Entidades</Name>
</ProjectReference>

The BRL references both the Data Access Layer (DAL) and Entity Layer (Entidades), providing business logic orchestration between data operations and entity models.

Layer 3: Data Access Layer (InapescaWeb.DAL)

Project Structure

The DAL contains data access classes following the pattern: MngDatos*

InapescaWeb.DAL.csproj:47-103

<Compile Include="clsDictionary.cs" />
<Compile Include="clsFunciones.cs" />
<Compile Include="MngDatosComision.cs" />
<Compile Include="MngDatosConfiguraciones.cs" />
<Compile Include="MngDatosContrato.cs" />
<Compile Include="MngDatosCuentasBancarias.cs" />
<Compile Include="MngDatosDgaipp.cs" />
<Compile Include="MngConexion.cs" />

Core Components

1. Connection Manager

Centralized database connection management:

MngConexion.cs:28-40

public class MngConexion
{
    public static MySqlConnection ConexionMysql;
    
    public static MySqlConnection getConexionMysql()
    {
        string CadenaConexionEncriptada = ConfigurationManager.AppSettings["localhost"];
        string CadenaConexion = MngEncriptacion.decripString(CadenaConexionEncriptada);
        ConexionMysql = new MySqlConnection(CadenaConexion);
        return ConexionMysql;
    }
    
    public static void disposeConexion()
    {
        ConexionMysql.Close();
        ConexionMysql.Dispose();
    }
}

The connection strings are encrypted using the MngEncriptacion class before being stored in web.config.

2. Data Access Classes

Each class handles CRUD operations for specific entities:

MngDatosComision.cs:39-61

public static ComisionProyecto RegresaDatos(string pPeriodo, string pClave, string pDependencia)
{
    string Query = "";
    Query += "SELECT SUM(COMBUST_EFECTIVO) AS COMBUSTIBLE, SUM(PEAJE) AS PEAJE, ";
    Query += "SUM(PASAJE) AS PASAJE, SUM(SINGLADURAS) AS SINGLADURAS, ";
    Query += "SUM(TOTAL_VIATICOS) AS TOTAL_VIATICOS, ";
    Query += "SUM(COMBUST_EFECTIVO) + SUM(PEAJE) + SUM(PASAJE) + ";
    Query += "SUM(SINGLADURAS) + SUM(TOTAL_VIATICOS) AS GRANTOTAL ";
    Query += "FROM crip_comision ";
    Query += "WHERE PERIODO='" + pPeriodo + "' ";
    Query += "AND CLV_PROY='" + pClave + "' ";
    Query += "AND CLV_DEP_PROY='" + pDependencia + "'";
    
    MySqlConnection ConexionMysql = MngConexion.getConexionMysql();
    MySqlCommand cmd = new MySqlCommand(Query, ConexionMysql);
    cmd.Connection.Open();
    MySqlDataReader Reader = cmd.ExecuteReader();
    
    ComisionProyecto oComision = new ComisionProyecto();
    while (Reader.Read())
    {
        oComision.Combustible = Convert.ToString(Reader["COMBUSTIBLE"]);
        oComision.Peaje = Convert.ToString(Reader["PEAJE"]);
        // ... map other fields
    }
    
    Reader.Close();
    MngConexion.disposeConexionSMAF(ConexionMysql);
    return oComision;
}

3. Database Provider

InapescaWeb.DAL.csproj:34-37

<Reference Include="MySql.Data, Version=6.6.5.0, Culture=neutral, 
                   PublicKeyToken=c5687fc88969c44d, processorArchitecture=MSIL">
  <HintPath>bin\Release\MySql.Data.dll</HintPath>
</Reference>

Entity Layer (InapescaWeb.Entidades)

The entity layer defines business objects used across all tiers:

Entity Classes

Core Entities
Supporting Entities
XML & Transparency

InapescaWeb.Entidades.csproj:43-87

<Compile Include="Comision.cs" />
<Compile Include="ComisionDetalle.cs" />
<Compile Include="ComisionProyecto.cs" />
<Compile Include="Comision_Extraordinaria.cs" />
<Compile Include="comprobacion.cs" />
<Compile Include="Proyecto.cs" />
<Compile Include="Usuario.cs" />
<Compile Include="Partidas.cs" />
<Compile Include="Pagos.cs" />
<Compile Include="Ministracion.cs" />

<Compile Include="CuentasBancarias.cs" />
<Compile Include="Entidad.cs" />
<Compile Include="Excel.cs" />
<Compile Include="GenerarRef.cs" />
<Compile Include="Itinerario.cs" />
<Compile Include="Login.cs" />
<Compile Include="Mail.cs" />
<Compile Include="Reporte.cs" />
<Compile Include="Transporte.cs" />
<Compile Include="Ubicacion.cs" />

<Compile Include="cfdiv33.cs" />
<Compile Include="cfdv4.cs" />
<Compile Include="Xml.cs" />
<Compile Include="Transparencia.cs" />
<Compile Include="Transparencia_Partidas.cs" />
<Compile Include="Transparencia_Vinculos.cs" />

Example Entity: Comision

Comision.cs:25-100

public class Comision
{
    private string lsFolio;
    private string lsFechaSol;
    private string lsfechaRespP;
    private string lsFechaVobo;
    private string lsFechaAut;
    private string lsUsuSol;
    private string lsUbicacion;
    private string lsArea;
    private string lsProyecto;
    private string lsDepProy;
    private string lsLugar;
    private string lsCapitulo;
    private string lsProceso;
    private string lsIndicador;
    private string lsPartPre;
    private string lsFechaI;
    private string lsFechaF;
    private string lsDiasT;
    private string lsDiasR;
    private string lsObjetivo;
    // ... additional fields
    
    // Public properties with getters/setters
    public string Folio { get; set; }
    public string FechaSolicitud { get; set; }
    // ...
}

Data Flow

The following diagram illustrates a typical request flow through all layers:

Layer Communication Patterns

1. Presentation to Business Layer

// ASPX Page calls business layer
protected void btnGuardar_Click(object sender, EventArgs e)
{
    Comision comision = new Comision();
    comision.Folio = txtFolio.Text;
    comision.Objetivo = txtObjetivo.Text;
    // ... set other properties
    
    bool resultado = MngNegocioComision.GuardarComision(comision);
    
    if (resultado)
        MostrarMensaje("Guardado exitoso");
}

2. Business to Data Layer

// Business layer delegates to data layer
public static bool GuardarComision(Comision comision)
{
    // Business validation
    if (!ValidarFechas(comision)) return false;
    
    // Delegate to data layer
    return MngDatosComision.InsertarComision(comision);
}

3. Data Layer to Database

// Data layer executes SQL
public static bool InsertarComision(Comision comision)
{
    MySqlConnection conn = MngConexion.getConexionMysql();
    string query = "INSERT INTO crip_comision VALUES (...)";
    MySqlCommand cmd = new MySqlCommand(query, conn);
    
    conn.Open();
    int result = cmd.ExecuteNonQuery();
    MngConexion.disposeConexion();
    
    return result > 0;
}

Benefits of This Architecture

Separation of Concerns

Each layer has a distinct responsibility:

Presentation: UI rendering and user interaction
Business: Rules, validation, and workflow
Data: Database operations and persistence

Maintainability

Changes to one layer have minimal impact on others. For example:

UI redesign doesn’t affect business logic
Business rule changes don’t require database modifications
Database optimizations are isolated to the DAL

Testability

Each layer can be tested independently:

Business logic can be unit tested without UI
Data access can be tested with mock databases
Integration testing validates layer interactions

Reusability

Business logic and data access components can be reused:

Same business rules for web and potential API
Shared entity classes across all layers
Common data access methods for similar operations

Best Practices Observed

Consistent Naming Conventions: MngNegocio* for business logic, MngDatos* for data access

Entity Usage: Shared entity objects across all layers

Connection Management: Centralized through MngConexion class

Security: Encrypted connection strings

Areas for Improvement

Some areas that could be enhanced:

Presentation Layer Dependencies: Currently references both BRL and DAL; should only reference BRL
SQL Injection Risk: Direct string concatenation in queries; should use parameterized queries
Exception Handling: Could benefit from more structured error handling
Repository Pattern: Could abstract data access further with repository interfaces

Architecture Overview

High-level system architecture

Database Schema

MySQL database structure and relationships

Architecture

Business Logic Layer

Data Access Layer

Entities

Integration

​Architecture Overview

​Layer 1: Presentation Layer (InapescaWeb)

​Project Structure

​Key Components

​1. ASPX Pages

​2. Utility Classes

​3. Project References

​Layer 2: Business Logic Layer (InapescaWeb.BRL)

​Project Structure

​Business Logic Classes

MngNegocioComision

MngNegocioComprobacion

MngNegocioPago

MngNegocioMinistracion

MngNegocioProyecto

MngNegocioUsuarios

MngNegocioViaticos

MngNegocioPartidas

MngNegocioReportesViaticos

​Example: Commission Business Logic

​Layer Dependencies

​Layer 3: Data Access Layer (InapescaWeb.DAL)

​Project Structure

​Core Components

​1. Connection Manager

​2. Data Access Classes

​3. Database Provider

​Entity Layer (InapescaWeb.Entidades)

​Entity Classes

​Example Entity: Comision

​Data Flow

​Layer Communication Patterns

​1. Presentation to Business Layer

​2. Business to Data Layer

​3. Data Layer to Database

​Benefits of This Architecture

​Best Practices Observed

​Areas for Improvement

​Related Documentation

Architecture Overview

Database Schema

Build docs developers (and LLMs) love

Architecture Overview

Layer 1: Presentation Layer (InapescaWeb)

Project Structure

Key Components

1. ASPX Pages

2. Utility Classes

3. Project References

Layer 2: Business Logic Layer (InapescaWeb.BRL)

Project Structure

Business Logic Classes

Example: Commission Business Logic

Layer Dependencies

Layer 3: Data Access Layer (InapescaWeb.DAL)

Project Structure

Core Components

1. Connection Manager

2. Data Access Classes

3. Database Provider

Entity Layer (InapescaWeb.Entidades)

Entity Classes

Example Entity: Comision

Data Flow

Layer Communication Patterns

1. Presentation to Business Layer

2. Business to Data Layer

3. Data Layer to Database

Benefits of This Architecture

Best Practices Observed

Areas for Improvement

Related Documentation