[FEATURE] Support missing DecayFunctions in FunctionScore

[stevejgordon]

Due to certain complexities with the DecayFunction union in the specification, the code generator is currently skipping these on the FunctionScore container type, which prevents the use of gauss, exp and linear functions. We need to solve this in the code generator so that these functions can be reintroduced in the 8.x client.

Please update by adding a thumbs-up reaction to this comment if this is a blocker for you. This helps us prioritise the work on new features.

[oscarlofwenhamn]

Is there any way to, for example, inject manually written JSON into FunctionScore to make use of the decay functions, or is the realistic solution simply to use the 7.17.x client (as recommended in the project README), in the case where decay functions are required?

[stevejgordon]

@oscarlofwenhamn You can't pass arbitrary JSON to FunctionScore. If this is the only blocker to upgrade, you could consider dropping to the Transport layer (available from the client instance), where you can send a complete request as JSON and handle the JSON response. Sticking with 7.17.x in compatibility mode until this is available is also an option.

[oscarlofwenhamn]

Clear and concise, thanks!

[ghost]

Is this still not adressed?

[flobernd]

@JanToreKyrdalen The code generator is currently being reworked to address this and other issues. A rough estimation for completion is end of Q1 2024.

[eCorke]

So, how's it going? It's been a year and three months from the original post, and 6 moths since Q1 2024 rough estimates. Any good news?

[flobernd]

Currently blocked until elastic/elasticsearch-specification#2545 is merged.

[flobernd]

Implemented in 8.14.4