Hello, Ron,

Thanks for preparing the materials. Now I understand your scenario.

You indeed have an element __metadata within your json response. I previously assumed that you were unaware of such element and were wondering where the error comes from.

The reason there is an issue mapping such element is that Pega does not allow to create properties starting with non-alphabetic characters. And the mode you chose for mapping implies automapping all elements including nested into properties with exactly same names. There is no such property (__metedata) in your data model (and cannot be, probably it is named in fact "Metadata" without underscores). The automapping would not work in such case.

Luckily there are other mapping options within connect-Rest rule. Use the option called map to Clipboard.

Select a Text property (e.g. create property named FullResponseJSON). The whole response in text format will be stored in mentioned property.

Then separately call an activity as the next step after your Connect-Rest rule is called and perform parsing of your FullResponseJSON.

In the activity you will need to call a JSON-type Datatransform. Create such rule and study it a little bit - it is very powerful - allows you to automap selectively and certain elements can be mapped to differently-named properties as required. Do not forget to pass a parameter DESERIALIZE to it (as you need it to map JSON to your class structure).

You can skip elements you do not need and __metadata can be mapped to property named Metadata. The nested elements can be even automapped.

Good luck.