Feature : Function Expression Defintions #59
Description
We had the following expression
"expression": "@and(equal(length(formvalue(logicalName())[idx()]['cvr']),8),isDigits(formvalue(logicalName())[idx()]['cvr']))"
and wanted to simplify the whole formvalue(logicalName())[idx()]['cvr'] into a currentCellValue function and coded this up:
public class CurrentCellValueFunction : Function
{
private readonly ILogger _logger;
private readonly ManifestAccessor _validationContext;
private readonly FormDataAccessor _formDataAccessor;
private readonly FormValueFunction _formValueFunction;
private readonly IdxFunction _idxFunction;
private readonly LogicalNameFunction _logicalNameFunction;
public CurrentCellValueFunction(
ILogger<CurrentCellValueFunction> logger,
ManifestAccessor validationContext,
FormDataAccessor formDataAccessor,
FormValueFunction formValueFunction,
IdxFunction idxFunction,
LogicalNameFunction logicalNameFunction) : base("currentCellValue")
{
_logger = logger ?? throw new ArgumentNullException(nameof(logger));
_validationContext = validationContext ?? throw new ArgumentNullException(nameof(validationContext));
_formDataAccessor = formDataAccessor ?? throw new ArgumentNullException(nameof(formDataAccessor));
_formValueFunction = formValueFunction;
_idxFunction = idxFunction;
_logicalNameFunction = logicalNameFunction;
}
public override async ValueTask<ValueContainer> ExecuteFunction(params ValueContainer[] parameters)
{
_logger.LogDebug("{FunctionName} entered", nameof(CurrentCellValueFunction));
try
{
//currentCellValue = formvalue(logicalName())[idx()]['cvr']
var logicalName = await _logicalNameFunction.ExecuteFunction();
var idx = await _idxFunction.ExecuteFunction();
var formvalue = await _formValueFunction.ExecuteFunction(logicalName);
var currentCell = formvalue[idx.GetValue<int>()][_validationContext.CurrentAttributeLogicalName];
return currentCell;
}
catch (Exception ex)
{
_logger.LogDebug(ex,"{FunctionName} failed", nameof(CurrentCellValueFunction));
throw;
}
}
}
however it bascially could have been automated in the framework to do Function expression Definitions:
services.AddFunctionExpresssionDefinition("currentCellValue", "@formvalue(logicalName())[idx()][attributeLogicalName()]")
or
services.AddFunctionExpresssionDefinition("currentCellValue", "formvalue(logicalName())[idx()][attributeLogicalName()]")