Trouble with saving data with 1 to 0..1 relation

Question

I have following simple data model: a parent entity which has 2 relations to 2 child entities called ChildA en ChildB. The type of relation is 1 to 0..1.
I have a (saved) record which has only a childA relation and execute following code (with button when record is shown):
screen.Parent.ChildA.deleteEntity();
screen.Parent.setChildB(new myapp.ChildB);
screen.Parent.ChildB.BProp1 = "test";
screen.Parent.ChildB.BProp2 = "test";
screen.Parent.ChildB.BProp3 = "test";
screen.Parent.ChildB.deleteEntity();
screen.Parent.setChildA(new myapp.ChildA);
screen.Parent.ChildA.AProp1 = "final";
screen.Parent.ChildA.AProp2 = "final";
When I hit save afterwards, I get:
What am I doing wrong?
This is what's going over the wire:
--batch_1c90-fa5c-f201
Content-Type: multipart/mixed; boundary=changeset_0c72-4e38-ea49
--changeset_0c72-4e38-ea49
Content-Type: application/http
Content-Transfer-Encoding: binary
POST ChildAs HTTP/1.1
Content-ID: 1
DataServiceVersion: 3.0
Accept: application/atomsvc+xml;q=0.8, application/json;odata=fullmetadata;q=0.7, application/json;q=0.5, */*;q=0.1
Content-Type: application/json;odata=verbose
MaxDataServiceVersion: 3.0
{"AProp1":"final","AProp2":"final"}
--changeset_0c72-4e38-ea49
Content-Type: application/http
Content-Transfer-Encoding: binary
MERGE Parents(13) HTTP/1.1
Content-ID: 0
DataServiceVersion: 3.0
If-Match: W/"X'000000000000273C'"
Prefer: return-content
Accept: application/atomsvc+xml;q=0.8, application/json;odata=fullmetadata;q=0.7, application/json;q=0.5, */*;q=0.1
Content-Type: application/json;odata=verbose
MaxDataServiceVersion: 3.0
{"ChildA":{"__metadata":{"uri":"$1"}}}
--changeset_0c72-4e38-ea49
Content-Type: application/http
Content-Transfer-Encoding: binary
DELETE ChildAs(13) HTTP/1.1
Content-ID: 2
DataServiceVersion: 3.0
If-Match: W/"X'000000000000273D'"
Accept: application/atomsvc+xml;q=0.8, application/json;odata=fullmetadata;q=0.7, application/json;q=0.5, */*;q=0.1
MaxDataServiceVersion: 3.0
--changeset_0c72-4e38-ea49
Content-Type: application/http
Content-Transfer-Encoding: binary
DELETE Parents(13)/$links/ChildB HTTP/1.1
Accept: application/atomsvc+xml;q=0.8, application/json;odata=fullmetadata;q=0.7, application/json;q=0.5, */*;q=0.1
MaxDataServiceVersion: 3.0
--changeset_0c72-4e38-ea49--
--batch_1c90-fa5c-f201--
paul van bladel ==independent enterprise application architect== http://blog.pragmaswitch.com

Answer 1

Hi Paul,
It is unusual for you to be posting a question you normally answer them :)
I decided to run some tests based on your example out of curiosity.
I got to test 'C' here is a workaround but crucially also not a single transaction.
myapp.AddEditParent1.TestEditC_execute = function (screen) {
var parent = screen.Parent,
child = parent.ChildA;
child.deleteEntity();
screen.details.dataWorkspace.ApplicationData.saveChanges()
.then(function (res) {
var childA = new myapp.ChildA();
childA.AProp1 = "final-C";
childA.AProp2 = "final-C";
childA.AProp3 = "final-C";
parent.setChildA(childA);
That got me thinking that actually the result of you code is an update in the end really ;)
myapp.AddEditParent1.TestEditD_execute = function (screen) {
screen.Parent.ChildA.AProp1 = "final-D";
screen.Parent.ChildA.AProp2 = "final-D";
screen.Parent.ChildA.AProp3 = "final-D";
So that was test D which obviously worked!
I think it is a bug.
Cheers
Dave
Dave Baker | AIDE for LightSwitch | Xpert360 blog | twitter : @xpert360 | Xpert360 website | Opinions are my own. For better forums, remember to mark posts as helpful/answer.