Description

Some field types are still missing support for synthetic source. We would like to implement the missing functionality adopting a strategy that allows us to use a stored field behind the scenes. The idea is to use the stored field later on to support reconstructing the original field value instead of reconstructing it from doc values.

The ones we expect to be used more frequently for logging and that we should prioritise when it comes to implementing support are:

• binary Add synthetic source support for binary fields #107549
• object (enabled: false) Track synthetic source for disabled objects #108051
• nested Store source for nested objects #108818
• long_range Implement synthetic source support for range fields #107081
• double_range Implement synthetic source support for range fields #107081
• date_range Implement synthetic source support for range fields #107081
• ip_range Implement synthetic source support for range fields #107081
• murmur3
• annotated-text Implement synthetic source support for annotated text field #107735

For fields that are less frequently used we will implement a less storage efficient fallback implementation of synthetic source. This implementation will cover all fields that are not currently supported and unblock their usage in logs index mode. Based on usage of such fields, more efficient implementation can be added.

• join Enable fallback synthetic source by default #109370
• completion Enable fallback synthetic source by default #109370
• search_as_you_type Add generic fallback implementation for synthetic source #108222, Support arrays in fallback synthetic source implementation #108878
• token_count Enable fallback synthetic source for token_count #109044
• sparse_vector Enable fallback synthetic source by default #109370
• rank_feature Enable fallback synthetic source by default #109370
• rank_features Enable fallback synthetic source by default #109370
• geo_shape Add synthetic source support for geo_shape via fallback implementation #108881
• point Enable fallback synthetic source for point and shape #109312
• shape Enable fallback synthetic source for point and shape #109312
• percolator Enable fallback synthetic source by default #109370

We would like to enable this feature by default if synthetic source is enable. This will enable usage of these field types for both logs and TSDB index mode.
In general support should be provided by making the stored property default to true when synthetic source is enabled. This implies we need to add the stored property even for fields that are missing it.

Once support is implemented please check the box next to the corresponding type and link the PR next to it.