Add support for inject_into paths instead of strings when injecting into JSON body

[erohmensing]

Problem

For certain use cases like GraphQL's variables, we want to inject a value (such as a pagination value or a cursor value for incremental) into not a top-level key, but a nested value (e.g. `{"variables": {"after": ""}}. Currently you can hack this a little bit for some values, like pagination cursor values, by providing an object as the cursor value:

However, for other fields you cannot, since you don't have control over the formatting of the value itself (e.g. as in incremental sync where you can only give the path to the value and the date formatter, but not the format of the object itself).

In any case, once you want to inject multiple keys into the top-level key, you then run into errors in the CDK about duplicate keys - so they don't merge.

Solution

We want to be able to inject into a key path on a Body JSON Payload instead of a key. The suggestion of the UX would be that if you have selected to inject into a Body JSON Payload, the following UI that you currently get:

would have Key Path instead of Key Value, and would give you the path input field

.

Note that for injecting into Query Parameter, Header, Path, or Body data (urlencoded form) the input fields should stay as they are.