/// <summary>
/// Asynchronously get next line and wait for a task (with a Tuple) to complete, ignoring tuples with nulls at end of each source.
/// </summary>
/// <param name="feeder">Feeder to read the line from (should be the 1st level LineFeeder, i.e. with LineFeederForSource as constituent feeders).</param>
/// <returns>Tuple containing text line and a source number or null at end.</returns>
internal static Tuple <ExternalLine, int> GetNextLineSynced(this ILineFeeder feeder)
{
var retVal = feeder.GetNextLineAsync().Result;
// retVal here is null at the very end of the entire sequence produced by LineFeeder.
// At end of each level of LineFeeder nesting (i.e. LineFeederForSource), it is a tuple containing null.
// Note that this assumes a single level of nesting, where LineFeeder is fed by LineFeederForSource (and not by LineFeeders (recursively)).
if (retVal == null)
{
return(null);
}
return(retVal.Item1 == null?GetNextLineSynced(feeder) : retVal);
}
/// <summary>
/// Performs one time initialization of the intake source(s), e.g. open input file(s).
/// This method is only called when the InitErrorOccurred property is accessed for the first time.
/// </summary>
/// <returns>true if initialization successful; false if not, e.g. file not found</returns>
private bool InitIntake()
{
var skipRepeatedHeader = _config.InputDataKind.CanHaveHeaderRow() && _config.HeadersInFirstInputRow && _config.InputHeadersRepeated;
var x12SegmentDelimiter = _config.InputDataKind == KindOfTextData.X12 ? _config.DefaultX12SegmentDelimiter ?? "~" : null; //note that default delimiter (~) is unlikely to be used as it get overwritten by pos 106 of ISA segment
// Note that in order for the exceptions to be caught in the try blocks below, CreateLineFeeder (or IntakeInitializer as applicable) processing
// must be eagerly evaluated (no deferred execution).
if (_intakeFromReader)
{
try
{
//In case both IntakeReaders and InputFileNames are present, then IntakeReaders wins
_intakeReader = _config.IntakeReaders == null?LineFeederCreator.CreateLineFeeder(_config.InputFileNames.ToListOfStrings('|'), _config.InputDataKind, _config.AsyncIntake, skipRepeatedHeader, x12SegmentDelimiter, _config.XmlJsonIntakeSettings)
: LineFeederCreator.CreateLineFeeder(_config.IntakeReaders(), _config.InputDataKind, _config.AsyncIntake, skipRepeatedHeader, x12SegmentDelimiter, _config.XmlJsonIntakeSettings);
}
catch (Exception ex)
{
//something went wrong with input file(s) or text reader(s), there is not much we can do other than to report it
var errMsg = _config.IntakeReaders == null ? $"Attempt to access input file(s) '{_config.InputFileNames}' failed."
: "Attempt to open text reader(s) failed.";
_config.Logger.LogFatal(errMsg, ex);
return(false);
}
return(true);
}
else //intake from IntakeSupplier (or IntakeSupplierAsync) function
{
string errMsg;
try
{
errMsg = _config.IntakeInitializer(_globalCache);
}
catch (Exception ex)
{
_config.Logger.LogFatal("Intake initializer threw exception.", ex);
return(false);
}
if (errMsg != null)
{
_config.Logger.LogFatal("Intake initializer failed:\r\n" + errMsg);
return(false);
}
return(true);
}
}