Why doesn't `getLedgerEntries` return the entire `LedgerEntry` type?

[Shaptic]

Context: Discord thread.

What problem does your feature solve?

Two fields are lost by getLedgerEntries returning the LedgerEntryData rather than the parent LedgerEntry object:

• lastModifiedLedgerSeq, the last time said entry was touched
• ext, the extension field which may be set for certain entries

What would you like to see?

An explanation for this design decision, a workaround, or a fix.

What alternatives are there?

Keeping things as-is, meaning downstream users lose access to the extension.

[leighmcculloch]

+1 This endpoint should imo return all the information unfiltered. Protocol 23 might be the best time to support this on a new method getLedgerEntries2, and return all the new information core is exposing, like status of whether it is live or archived too.

[Shaptic]

Options I can see:

1. New endpoint or param that changes return schema (non-breaking for API, breaking for apps to use)
2. Add missing fields to existing endpoint (non-breaking for all)
3. Change the xdr field to be LedgerEntry (breaking for all)
4. Change the xdr field to be LedgerEntry but update SDKs to do (2) (breaking for API, non-breaking for apps)

[FrankSzendzielarz]

Another slight variant might be to introduce a version number into the RPC route to handle API versioning more generally.

[FrankSzendzielarz]

Another suggestion, though I don't know if this is best dealt with as a separate feature request, relates to this issue: stellar/stellar-docs#1399

Something changed that the SDK stopped being able to handle transaction results, as the server started returning string type enums instead of integer type enums for the StateChange Type. (It was a coincidence...issue in SDK probably, not server change) This led me to wonder how I could track the server vs rpc spec versions.
So perhaps another artifact that could be considered is to have the RPC spec returned by the RPC server as part of GetVersionInfo, or as a new rpc method This would allow testnet and mainnet etc to have their own rpc APIs, for example.