Add support for hashmaps

[WisdomPill]

Problem Statement
django-redis should introduce hasmaps and support basic operations, hset, hdel, hlen, hkeys and hexists.

Describe the solution you'd like
Add an interface similar to redis-py to support hasps

[YashKumarVerma]

@WisdomPill is this one resolved or are we still looking for help here? I'm interested if its needed

[WisdomPill]

still looking for an implementation, #654 is a very good attempt at it on the sets side, if you want to propose a solution you're very welcome to do so 😄

[LucianaAG]

is available to work on this issue?

[WisdomPill]

Hello @LucianaAG I think @kysre is doing all right here, you can try to do something similar to his PR for sets maybe?

[WisdomPill]

support for hset, hlen, hdel, hkeys and hexists has been added thanks to the efforts of @kysre.

Things left to add to make it complete are.

• tests for in ShardClient (this should be fairly easy, replacing get_client with method with make_key and get_server based on the key should do the trick like it is done in other ShardedClient methods)
• HDEL
• HEXISTS
• HGET quite important
• HGETALL quite important
• HINCRBY
• HINCRYBYFLOAT
• HKEYS
• HLEN
• HMGET
• HMSET
• HRANDFIELD not relevant
• HSCAN
• HSET
• HSETNX relevant could be implemented in .hset()
• HSTRLEN not relevant
• HVALS not relevant

any contribution is welcome, I consider this a beginner friendly issue

[rootart]

Hi, @WisdomPill I extended support for the missing hashmap functions and would appreciate your feedback when you have some spare time.
HINCRYBYFLOAT is one of the functions that is missing and I think it would require a bit more work to implement given how we do the decoding/encoding of the values https://github.com/jazzband/django-redis/blob/master/django_redis/client/default.py#L509-L518 I worry if we explicitly store the float value it would come up as incompatible change. Let me know what are your thoughts on this and thanks again.