He estado leyendo Trabajar eficazmente con código heredado y código limpio con el objetivo de aprender estrategias sobre cómo comenzar a limpiar la base de código existente de una aplicación de formularios web ASP.NET de gran tamaño.
Este sistema existe desde 2005 y desde entonces ha experimentado una serie de mejoras. Originalmente, el código se estructuraba de la siguiente manera (y todavía se estructura en gran medida de esta manera):
- ASP.NET (aspx / ascx)
- Código subyacente (c #)
- Capa de lógica empresarial (c #)
- Capa de acceso a datos (c #)
- Base de datos (Oracle)
El problema principal es que el código está enmascarado por procedimientos como orientado a objetos. Prácticamente viola todas las pautas descritas en ambos libros.
Este es un ejemplo de una clase típica en la capa de lógica de negocios:
public class AddressBO
{
public TransferObject GetAddress(string addressID)
{
if (StringUtils.IsNull(addressID))
{
throw new ValidationException("Address ID must be entered");
}
AddressDAO addressDAO = new AddressDAO();
return addressDAO.GetAddress(addressID);
}
public TransferObject Insert(TransferObject addressDetails)
{
if (StringUtils.IsNull(addressDetails.GetString("EVENT_ID")) ||
StringUtils.IsNull(addressDetails.GetString("LOCALITY")) ||
StringUtils.IsNull(addressDetails.GetString("ADDRESS_TARGET")) ||
StringUtils.IsNull(addressDetails.GetString("ADDRESS_TYPE_CODE")) ||
StringUtils.IsNull(addressDetails.GetString("CREATED_BY")))
{
throw new ValidationException(
"You must enter an Event ID, Locality, Address Target, Address Type Code and Created By.");
}
string addressID = Sequence.GetNextValue("ADDRESS_ID_SEQ");
addressDetails.SetValue("ADDRESS_ID", addressID);
string syncID = Sequence.GetNextValue("SYNC_ID_SEQ");
addressDetails.SetValue("SYNC_ADDRESS_ID", syncID);
TransferObject syncDetails = new TransferObject();
Transaction transaction = new Transaction();
try
{
AddressDAO addressDAO = new AddressDAO();
addressDAO.Insert(addressDetails, transaction);
// insert the record for the target
TransferObject addressTargetDetails = new TransferObject();
switch (addressDetails.GetString("ADDRESS_TARGET"))
{
case "PARTY_ADDRESSES":
{
addressTargetDetails.SetValue("ADDRESS_ID", addressID);
addressTargetDetails.SetValue("ADDRESS_TYPE_CODE",
addressDetails.GetString("ADDRESS_TYPE_CODE"));
addressTargetDetails.SetValue("PARTY_ID", addressDetails.GetString("PARTY_ID"));
addressTargetDetails.SetValue("EVENT_ID", addressDetails.GetString("EVENT_ID"));
addressTargetDetails.SetValue("CREATED_BY", addressDetails.GetString("CREATED_BY"));
addressDAO.InsertPartyAddress(addressTargetDetails, transaction);
break;
}
case "PARTY_CONTACT_ADDRESSES":
{
addressTargetDetails.SetValue("ADDRESS_ID", addressID);
addressTargetDetails.SetValue("ADDRESS_TYPE_CODE",
addressDetails.GetString("ADDRESS_TYPE_CODE"));
addressTargetDetails.SetValue("PUBLIC_RELEASE_FLAG",
addressDetails.GetString("PUBLIC_RELEASE_FLAG"));
addressTargetDetails.SetValue("CONTACT_ID", addressDetails.GetString("CONTACT_ID"));
addressTargetDetails.SetValue("EVENT_ID", addressDetails.GetString("EVENT_ID"));
addressTargetDetails.SetValue("CREATED_BY", addressDetails.GetString("CREATED_BY"));
addressDAO.InsertContactAddress(addressTargetDetails, transaction);
break;
}
<< many more cases here >>
default:
{
break;
}
}
// synchronise
SynchronisationBO synchronisationBO = new SynchronisationBO();
syncDetails = synchronisationBO.Synchronise("I", transaction,
"ADDRESSES", addressDetails.GetString("ADDRESS_TARGET"),
addressDetails, addressTargetDetails);
// commit
transaction.Commit();
}
catch (Exception)
{
transaction.Rollback();
throw;
}
return new TransferObject("ADDRESS_ID", addressID, "SYNC_DETAILS", syncDetails);
}
<< many more methods are here >>
}
Tiene mucha duplicación, la clase tiene una serie de responsabilidades, etc., etc., generalmente es un código "no limpio".
Todo el código en todo el sistema depende de implementaciones concretas.
Este es un ejemplo de una clase típica en la capa de acceso a datos:
public class AddressDAO : GenericDAO
{
public static readonly string BASE_SQL_ADDRESSES =
"SELECT " +
" a.address_id, " +
" a.event_id, " +
" a.flat_unit_type_code, " +
" fut.description as flat_unit_description, " +
" a.flat_unit_num, " +
" a.floor_level_code, " +
" fl.description as floor_level_description, " +
" a.floor_level_num, " +
" a.building_name, " +
" a.lot_number, " +
" a.street_number, " +
" a.street_name, " +
" a.street_type_code, " +
" st.description as street_type_description, " +
" a.street_suffix_code, " +
" ss.description as street_suffix_description, " +
" a.postal_delivery_type_code, " +
" pdt.description as postal_delivery_description, " +
" a.postal_delivery_num, " +
" a.locality, " +
" a.state_code, " +
" s.description as state_description, " +
" a.postcode, " +
" a.country, " +
" a.lock_num, " +
" a.created_by, " +
" TO_CHAR(a.created_datetime, '" + SQL_DATETIME_FORMAT + "') as created_datetime, " +
" a.last_updated_by, " +
" TO_CHAR(a.last_updated_datetime, '" + SQL_DATETIME_FORMAT + "') as last_updated_datetime, " +
" a.sync_address_id, " +
" a.lat," +
" a.lon, " +
" a.validation_confidence, " +
" a.validation_quality, " +
" a.validation_status " +
"FROM ADDRESSES a, FLAT_UNIT_TYPES fut, FLOOR_LEVELS fl, STREET_TYPES st, " +
" STREET_SUFFIXES ss, POSTAL_DELIVERY_TYPES pdt, STATES s " +
"WHERE a.flat_unit_type_code = fut.flat_unit_type_code(+) " +
"AND a.floor_level_code = fl.floor_level_code(+) " +
"AND a.street_type_code = st.street_type_code(+) " +
"AND a.street_suffix_code = ss.street_suffix_code(+) " +
"AND a.postal_delivery_type_code = pdt.postal_delivery_type_code(+) " +
"AND a.state_code = s.state_code(+) ";
public TransferObject GetAddress(string addressID)
{
//Build the SELECT Statement
StringBuilder selectStatement = new StringBuilder(BASE_SQL_ADDRESSES);
//Add WHERE condition
selectStatement.Append(" AND a.address_id = :addressID");
ArrayList parameters = new ArrayList{DBUtils.CreateOracleParameter("addressID", OracleDbType.Decimal, addressID)};
// Execute the SELECT statement
Query query = new Query();
DataSet results = query.Execute(selectStatement.ToString(), parameters);
// Check if 0 or more than one rows returned
if (results.Tables[0].Rows.Count == 0)
{
throw new NoDataFoundException();
}
if (results.Tables[0].Rows.Count > 1)
{
throw new TooManyRowsException();
}
// Return a TransferObject containing the values
return new TransferObject(results);
}
public void Insert(TransferObject insertValues, Transaction transaction)
{
// Store Values
string addressID = insertValues.GetString("ADDRESS_ID");
string syncAddressID = insertValues.GetString("SYNC_ADDRESS_ID");
string eventID = insertValues.GetString("EVENT_ID");
string createdBy = insertValues.GetString("CREATED_BY");
// postal delivery
string postalDeliveryTypeCode = insertValues.GetString("POSTAL_DELIVERY_TYPE_CODE");
string postalDeliveryNum = insertValues.GetString("POSTAL_DELIVERY_NUM");
// unit/building
string flatUnitTypeCode = insertValues.GetString("FLAT_UNIT_TYPE_CODE");
string flatUnitNum = insertValues.GetString("FLAT_UNIT_NUM");
string floorLevelCode = insertValues.GetString("FLOOR_LEVEL_CODE");
string floorLevelNum = insertValues.GetString("FLOOR_LEVEL_NUM");
string buildingName = insertValues.GetString("BUILDING_NAME");
// street
string lotNumber = insertValues.GetString("LOT_NUMBER");
string streetNumber = insertValues.GetString("STREET_NUMBER");
string streetName = insertValues.GetString("STREET_NAME");
string streetTypeCode = insertValues.GetString("STREET_TYPE_CODE");
string streetSuffixCode = insertValues.GetString("STREET_SUFFIX_CODE");
// locality/state/postcode/country
string locality = insertValues.GetString("LOCALITY");
string stateCode = insertValues.GetString("STATE_CODE");
string postcode = insertValues.GetString("POSTCODE");
string country = insertValues.GetString("COUNTRY");
// esms address
string esmsAddress = insertValues.GetString("ESMS_ADDRESS");
//address/GPS
string lat = insertValues.GetString("LAT");
string lon = insertValues.GetString("LON");
string zoom = insertValues.GetString("ZOOM");
//string validateDate = insertValues.GetString("VALIDATED_DATE");
string validatedBy = insertValues.GetString("VALIDATED_BY");
string confidence = insertValues.GetString("VALIDATION_CONFIDENCE");
string status = insertValues.GetString("VALIDATION_STATUS");
string quality = insertValues.GetString("VALIDATION_QUALITY");
// the insert statement
StringBuilder insertStatement = new StringBuilder("INSERT INTO ADDRESSES (");
StringBuilder valuesStatement = new StringBuilder("VALUES (");
ArrayList parameters = new ArrayList();
// build the insert statement
insertStatement.Append("ADDRESS_ID, EVENT_ID, CREATED_BY, CREATED_DATETIME, LOCK_NUM ");
valuesStatement.Append(":addressID, :eventID, :createdBy, SYSDATE, 1 ");
parameters.Add(DBUtils.CreateOracleParameter("addressID", OracleDbType.Decimal, addressID));
parameters.Add(DBUtils.CreateOracleParameter("eventID", OracleDbType.Decimal, eventID));
parameters.Add(DBUtils.CreateOracleParameter("createdBy", OracleDbType.Varchar2, createdBy));
// build the insert statement
if (!StringUtils.IsNull(syncAddressID))
{
insertStatement.Append(", SYNC_ADDRESS_ID");
valuesStatement.Append(", :syncAddressID");
parameters.Add(DBUtils.CreateOracleParameter("syncAddressID", OracleDbType.Decimal, syncAddressID));
}
if (!StringUtils.IsNull(postalDeliveryTypeCode))
{
insertStatement.Append(", POSTAL_DELIVERY_TYPE_CODE");
valuesStatement.Append(", :postalDeliveryTypeCode ");
parameters.Add(DBUtils.CreateOracleParameter("postalDeliveryTypeCode", OracleDbType.Varchar2, postalDeliveryTypeCode));
}
if (!StringUtils.IsNull(postalDeliveryNum))
{
insertStatement.Append(", POSTAL_DELIVERY_NUM");
valuesStatement.Append(", :postalDeliveryNum ");
parameters.Add(DBUtils.CreateOracleParameter("postalDeliveryNum", OracleDbType.Varchar2, postalDeliveryNum));
}
if (!StringUtils.IsNull(flatUnitTypeCode))
{
insertStatement.Append(", FLAT_UNIT_TYPE_CODE");
valuesStatement.Append(", :flatUnitTypeCode ");
parameters.Add(DBUtils.CreateOracleParameter("flatUnitTypeCode", OracleDbType.Varchar2, flatUnitTypeCode));
}
if (!StringUtils.IsNull(lat))
{
insertStatement.Append(", LAT");
valuesStatement.Append(", :lat ");
parameters.Add(DBUtils.CreateOracleParameter("lat", OracleDbType.Decimal, lat));
}
if (!StringUtils.IsNull(lon))
{
insertStatement.Append(", LON");
valuesStatement.Append(", :lon ");
parameters.Add(DBUtils.CreateOracleParameter("lon", OracleDbType.Decimal, lon));
}
if (!StringUtils.IsNull(zoom))
{
insertStatement.Append(", ZOOM");
valuesStatement.Append(", :zoom ");
parameters.Add(DBUtils.CreateOracleParameter("zoom", OracleDbType.Decimal, zoom));
}
if (!StringUtils.IsNull(flatUnitNum))
{
insertStatement.Append(", FLAT_UNIT_NUM");
valuesStatement.Append(", :flatUnitNum ");
parameters.Add(DBUtils.CreateOracleParameter("flatUnitNum", OracleDbType.Varchar2, flatUnitNum));
}
if (!StringUtils.IsNull(floorLevelCode))
{
insertStatement.Append(", FLOOR_LEVEL_CODE");
valuesStatement.Append(", :floorLevelCode ");
parameters.Add(DBUtils.CreateOracleParameter("floorLevelCode", OracleDbType.Varchar2, floorLevelCode));
}
if (!StringUtils.IsNull(floorLevelNum))
{
insertStatement.Append(", FLOOR_LEVEL_NUM");
valuesStatement.Append(", :floorLevelNum ");
parameters.Add(DBUtils.CreateOracleParameter("floorLevelNum", OracleDbType.Varchar2, floorLevelNum));
}
if (!StringUtils.IsNull(buildingName))
{
insertStatement.Append(", BUILDING_NAME");
valuesStatement.Append(", :buildingName ");
parameters.Add(DBUtils.CreateOracleParameter("buildingName", OracleDbType.Varchar2, buildingName));
}
if (!StringUtils.IsNull(lotNumber))
{
insertStatement.Append(", LOT_NUMBER");
valuesStatement.Append(", :lotNumber ");
parameters.Add(DBUtils.CreateOracleParameter("lotNumber", OracleDbType.Varchar2, lotNumber));
}
if (!StringUtils.IsNull(streetNumber))
{
insertStatement.Append(", STREET_NUMBER");
valuesStatement.Append(", :streetNumber ");
parameters.Add(DBUtils.CreateOracleParameter("streetNumber", OracleDbType.Varchar2, streetNumber));
}
if (!StringUtils.IsNull(streetName))
{
insertStatement.Append(", STREET_NAME");
valuesStatement.Append(", :streetName ");
parameters.Add(DBUtils.CreateOracleParameter("streetName", OracleDbType.Varchar2, streetName));
}
if (!StringUtils.IsNull(streetTypeCode))
{
insertStatement.Append(", STREET_TYPE_CODE");
valuesStatement.Append(", :streetTypeCode ");
parameters.Add(DBUtils.CreateOracleParameter("streetTypeCode", OracleDbType.Varchar2, streetTypeCode));
}
if (!StringUtils.IsNull(streetSuffixCode))
{
insertStatement.Append(", STREET_SUFFIX_CODE");
valuesStatement.Append(", :streetSuffixCode ");
parameters.Add(DBUtils.CreateOracleParameter("streetSuffixCode", OracleDbType.Varchar2, streetSuffixCode));
}
if (!StringUtils.IsNull(locality))
{
insertStatement.Append(", LOCALITY");
valuesStatement.Append(", :locality");
parameters.Add(DBUtils.CreateOracleParameter("locality", OracleDbType.Varchar2, locality));
}
if (!StringUtils.IsNull(stateCode))
{
insertStatement.Append(", STATE_CODE");
valuesStatement.Append(", :stateCode");
parameters.Add(DBUtils.CreateOracleParameter("stateCode", OracleDbType.Varchar2, stateCode));
}
if (!StringUtils.IsNull(postcode))
{
insertStatement.Append(", POSTCODE");
valuesStatement.Append(", :postcode ");
parameters.Add(DBUtils.CreateOracleParameter("postcode", OracleDbType.Varchar2, postcode));
}
if (!StringUtils.IsNull(country))
{
insertStatement.Append(", COUNTRY");
valuesStatement.Append(", :country ");
parameters.Add(DBUtils.CreateOracleParameter("country", OracleDbType.Varchar2, country));
}
if (!StringUtils.IsNull(esmsAddress))
{
insertStatement.Append(", ESMS_ADDRESS");
valuesStatement.Append(", :esmsAddress ");
parameters.Add(DBUtils.CreateOracleParameter("esmsAddress", OracleDbType.Varchar2, esmsAddress));
}
if (!StringUtils.IsNull(validatedBy))
{
insertStatement.Append(", VALIDATED_DATE");
valuesStatement.Append(", SYSDATE ");
insertStatement.Append(", VALIDATED_BY");
valuesStatement.Append(", :validatedBy ");
parameters.Add(DBUtils.CreateOracleParameter("validatedBy", OracleDbType.Varchar2, validatedBy));
}
if (!StringUtils.IsNull(confidence))
{
insertStatement.Append(", VALIDATION_CONFIDENCE");
valuesStatement.Append(", :confidence ");
parameters.Add(DBUtils.CreateOracleParameter("confidence", OracleDbType.Decimal, confidence));
}
if (!StringUtils.IsNull(status))
{
insertStatement.Append(", VALIDATION_STATUS");
valuesStatement.Append(", :status ");
parameters.Add(DBUtils.CreateOracleParameter("status", OracleDbType.Varchar2, status));
}
if (!StringUtils.IsNull(quality))
{
insertStatement.Append(", VALIDATION_QUALITY");
valuesStatement.Append(", :quality ");
parameters.Add(DBUtils.CreateOracleParameter("quality", OracleDbType.Decimal, quality));
}
// finish off the statement
insertStatement.Append(") ");
valuesStatement.Append(")");
// build the insert statement
string sql = insertStatement + valuesStatement.ToString();
// Execute the INSERT Statement
Dml dmlDAO = new Dml();
int rowsAffected = dmlDAO.Execute(sql, transaction, parameters);
if (rowsAffected == 0)
{
throw new NoRowsAffectedException();
}
}
<< many more methods go here >>
}
Este sistema fue desarrollado por mí y un pequeño equipo en 2005 después de un curso de .NET de 1 semana. Antes que mi experiencia fue en aplicaciones cliente-servidor. En los últimos 5 años, he llegado a reconocer los beneficios de las pruebas unitarias automatizadas, las pruebas de integración automatizadas y las pruebas de aceptación automatizadas (utilizando Selenium o equivalente), pero la base de código actual parece imposible de introducir estos conceptos.
Ahora estamos comenzando a trabajar en un importante proyecto de mejora con plazos ajustados. El equipo consta de 5 desarrolladores .NET: 2 desarrolladores con algunos años de experiencia .NET y otros 3 con poca o ninguna experiencia .NET. Ninguno de los miembros del equipo (incluido yo mismo) tiene experiencia en el uso de pruebas de unidades .NET o marcos de imitación.
¿Qué estrategia usarías para hacer este código más limpio, más orientado a objetos, comprobable y mantenible?