Inconsistent `JSON.OBJLEN`: Add error-message for when querying non-existent key

[paulwalrath]

Steps to reproduce

When I was writing the documentation for the JSON.OBJLEN command, I made it to be similar to the JSON.OBJKEYS command, which is very similar.

But while investigating, I discovered an inconsistency in the JSON.OBJLEN command; it doesn't return an error message when you use it to query a non-existent key.

To reproduce, try running the JSON.OBJLEN command on a key that you know does not exist in the datastore. You will get a blank response. But it should return an error message saying the key does not exist.

Expected output

If you use the command to query a key that doesn't exist, it should give an error:

dicedb> JSON.OBJLEN nonexistent_key $
(error) ERR could not perform this operation on a key that doesn't exist

Observed output

Presently, it does not return an error:

dicedb> JSON.OBJLEN nonexistent_key $
Error: redis: nil

Expectations for resolution

This issue will be considered resolved when the following things are done

1. the implementation for that command is in the evalJSONOBJLEN() function in internal/eval/store_eval.go. Change the EvalResponse object so it returns the diceerrors.ErrKeyDoesNotExist error, instead of nil.
2. modify test cases in integration_tests for this change.

[akhilk2802]

Hi @paulwalrat, are you still working on this ? would love to start with this

[paulwalrath]

Hi @paulwalrat, are you still working on this ? would love to start with this

Hi there. Sorry, there's nothing to do. The work is already done (see PR 1354) and is waiting to be merged.

[akhilk2802]

Got it

[lucifercr07]

Closing, merged as part of https://github.com/DiceDB/dice/pull/1354.