Difficult to handle nested tokens in IResolutionPolicy implementations

[brettsam]

PR Azure/azure-webjobs-sdk-extensions#354 exposed some issues with our IResolutionPolicy. In short, nested tokens are really hard to handle in the same way that our other bindings handle them. We'll need to restructure how this works in order to get this working.

This directly affects Table and CosmosDB -- neither of their query bindings can handle nested property bindings today.

There's a pretty lengthy internal discussion on this that I won't paste here, but should be consulted when it comes time to do this.

[piquet-h]

Given this is 12 months old - what information is required to progress this?

A common pattern is responding to event grid notifications. If the data is in the EventGrid schema notification, then it's going to be under the data property, which means, by default, it's nested.

I'd really like to be able to write a function.json with code similar to
"sqlQuery": "select * from transactions where transactions.atmVersion= 'strings/{data.version}'"

[antempus]

Jumping in here to say that this would be a much-needed improvement given that passing in multiple inputs isn't really supported; this would solve the need by allowing us to just use nested props on a complex object.

[u000fsr]

any updates on the ability to nested properties in cosmos sql query?

[rubenmamo]

Solving this would be a great help and would really simplify development of functions which access cosmos db and where you pass some sort of identifier as a header

[brettsam]

There's no update on this. It would require a restructuring of how our bindings pass information, and since there's a way to do this without any change, we've prioritized this lower than other issues.

The recommended solution is to pull in the Cosmos SDK and run the query in the function itself. For example, the code where we do this from our binding (which likely can be simplified if it's not a binding) is here: https://github.com/Azure/azure-webjobs-sdk-extensions/blob/dev/src/WebJobs.Extensions.CosmosDB/Bindings/CosmosDBEnumerableBuilder.cs#L27-L48

It's not as easy as using the notation above, but hopefully this isn't a blocker.