#499: Add support for command JSON.OBJLEN

[phaneesh707]

Issue

Issue fixed : #499

Description

This PR introduces the new command JSON.OBJLEN

1. Implementation for JSON.OBJLEN ref: RedisJSON , JSON.OBJLEN
2. Add unit tests
3. Add integration tests
4. Add benchmark

Dice DB(CLI demo)

Redis

Testing details

1. Units tests

2. Integration tests

3. Benchmarks

[lucifercr07]

@phaneesh707 thanks for contributing, have some minor comments. Please have a look once.

[lucifercr07]

. is not an invalid path. We should return the length of complete parent object if the arg contains . as path.

127.0.0.1:6379> JSON.OBJLEN doc .
(integer) 2

[phaneesh707]

So when i use JSON.OBJLEN doc . the library is not able to parse it , gives this error - ERRR not terminated at 2 in . , but it works fine for JSON.OBJLEN doc .person or something similar.so should i just do this ?

if path == "."{
    path = "$"
}

[phaneesh707]

@lucifercr07 any suggestion for ^^??

[JyotinderSingh]

Let's tackle this separately. Created issue #603 for this

[JyotinderSingh]

Thanks for these changes @phaneesh707. I have left a few comments.