Inline flows

01inlinedesign.cs

// flow defined inline
public ExportReport Export(DateTime fromMonth, DateTime toMonth) {
	// create month range
	// get balance sheets for month range
	// extract transaction items
	// create filename
	// export
	// create export report
}

02inlineimplementation.cs

// flow implemented inline
public ExportReport Export(DateTime fromMonth, DateTime toMonth) {
	// create month range
	if (toMonth == DateTime.MinValue) toMonth = fromMonth;
	fromMonth = fromMonth.ToMonth ();
	toMonth = toMonth.ToMonth ();

	if (toMonth < fromMonth) {
		var t = toMonth;
		toMonth = fromMonth;
		fromMonth = t;
	}

	var months = new List<DateTime> ();
	var currMonth = fromMonth;
	while (currMonth <= toMonth) {
		months.Add (currMonth);
		currMonth = currMonth.AddMonths (1);
	}
		
	// get balance sheets for month range
	var allTx = this.repo.Load_all_transactions ();
	var cb = this.cashbookFactory (allTx.ToArray());
	var balanceSheets = months.Select (m => cb [m]);
	// extract transaction items
	var txItems = balanceSheets.SelectMany (bs => bs.TransactionItems).ToArray();

	// create filename
	var filename = string.Format ("cashbook-{0:yyyyMM}-{1:yyyyMM}.csv", fromMonth, toMonth);

	// write items to file
	using(var sw = new StreamWriter(filename)) {
	foreach(var txi in txItems)
		sw.WriteLine("{0:d};\"{1}\";{2:f}", txi.TransactionDate, txi.Description, txi.Value);
	}
				
	return new ExportReport{ Filename = filename, NumberOfTransactions =  txItems.Length };
}

03iospimplementation.cs

// flow implemented as true integration
public ExportReport Export(DateTime fromMonth, DateTime toMonth) {
	var allTx = this.repo.Load_all_transactions ().ToArray();
	var cashbook = this.cashbookFactory (allTx);

	var months = fromMonth.ExtendTo (toMonth);
	var txItems = cashbook.Get_balance_sheet_items_in_month_range (months);

	var filepath = string.Format ("cashbook-{0:yyyyMM}-{1:yyyyMM}.csv", fromMonth, toMonth);
	this.csvProvider.Export (txItems, filepath);
		
	return new ExportReport{ Filename = filepath, NumberOfTransactions =  txItems.Length };
}