I asked this question before within an other subject, but I decided to extract it and create a separate topic. Hope you can help:
So I'm finally integrating a sap odata service (reverse proxy) but I'm still struggling with the association part. I use the method as described in the tutorials (of the purchase order example) but somehow I get a 403 error (nothing more). Funny thing is that when I get the url from debugging and put that into the browser, all works well. I included the current CSRF token as well in the call.
So, current call is: $ENTITYFROMSAP/TO_OTHERENTITYDeferred (just like the Purchaseorder example) which gives me 403 errors.
Anyone got an idea what could cause the problem of 403? To put this into perspective: calling get_list and create work as designed. No problems here. It is only the deferred calls which do not work. I also asked the support people of the company who maintain the reversed proxy to check on the network calls.
Well, we've finally cracked the case! I had some help of my fellow enthousiasts at Mendix. The problem is that when the SAP Gateway server returns the call, all metadata (uri etc) is provided in full. This can't be filtered, it is just how it is and sometimes to much. Lets look at the basic call (build up from the global variable and some string concatenations) to get some kind of list (pseudo code, but you get the idea)
Based on that we get a list of entities. They have associations with some “otherentity”. To call this, the gateway server returns
Put it into the browser, all works fine. Put it through Mendix, it returns an 403 error. It looks like the browser "removes” the port part of the uri. Therefor it works on the browser. Mendix doesn't, therefor the call goes wrong (I'll post that as an idea as well to fix it :-) )
I finally decided to, before I call the to_deferred part of the entity, remove the port part in the URI. Execute → Result! Works fine!
I'll try to create a java action for this (myfirstmendixjavaaction) and will use it within my project. This action will somehow remore the :port part in the uri and call it like that. Not sure if I can make it fully bulletproof but if will do for now!
Hope this helps a little. Removing the :port part solved the issue.
All the best and thanks again to my Mendix colleagues for their help!