Documentation:Receive post data not known at design time

With MDriven Turnkey it is easy to construct public Rest services of strict model typed data as defined by a ViewModel as described here.

Sometimes you may, however, have the need to receive data in a post that is not known at design time.

One specific scenario we have seen was the integration of the Texture-online-editor, this editor will post all the document data as several form files - but we do not know the names of these files or their number - at design time.

To handle his case we have introduced the following pattern:

Having a ViewModel (With RestAllowed=true) and posting data to it - the following "contract" is now available (2019-07):

If a mutable (possible to change) multilink column named FormFields(1) is found - posted form fields NOT found as named columns (in this example Attribute1(9) will match form field for Attribute1 - and thus Attribute1 will not be left to handle with FormFields ) will create new objects and Key(3) and Value(4) columns will get populated with the form field values.

Also FormFiles(2) can be a mutable multilink and if found we will add new objects to the association and populate the following attributes , if found, from posted files: Name(5), FileName(6), ContentType(7), Bytes(8).

The Bytes property must be Blob or Blob? - all other properties are strings.

Example code

We used the following c# to verify this function:

	MemoryStream ms = new MemoryStream();
	ms.Write(new byte[10] { 1, 2, 3, 4, 45, 5, 6, 7, 8, 9 }, 0, 10);
	ms.Position = 0;
	HttpClient c = new HttpClient();
	var content = new MultipartFormDataContent();
	content.Add(new StringContent("Ticks:"+DateTime.Now.Ticks.ToString()), "Attribute1");
	content.Add(new StringContent("hello"), "thename");
	content.Add(new ByteArrayContent(new byte[10] { 1, 2, 3, 4, 45, 5, 6, 7, 8, 9 }, 0, 10), "thename", "somefilename.txt");
	var streamcontent = new StreamContent(ms);
	streamcontent.Headers.ContentType = new MediaTypeHeaderValue("text/html");
	content.Add(streamcontent, "thename3", "thefilename.WithExtension");
	var res = c.PostAsync("http://localhost:5052/TurnkeyRest/Post?command=TestRestPost&id=1!0", content).Result;

The above code resultet in this output:

The data was displayed from a ViewModel looking like this:

x