How to switch from hmset() to hset() in Redis?

Question

I get the deprication warning, that Redis.hmset() is deprecated. Use Redis.hset() instead.

However hset() takes a third parameter and I can't figure out what name is supposed to be.

info = {'users': 10, "timestamp": datetime.utcnow().strftime('%Y-%m-%d %H:%M:%S')}
r.hmset("myKey", info)

The above works, but this requires a first parameter called name.

r.hset(name, "myKey", info)

Comparing the hset vs hmset in docs isn't clear to me.

Planetary

You can use hset("myKey", mapping=info). – Iliad

Sorry doesn't seem to accept it. – Planetary

It appears the mapping kwarg was added in 3.5.0 (Apr 29, 2020). If your version is older, you will need to do as @Ersoy suggests. – Iliad

@hmm it may be related to library's min-redis version. HSET with multiple field/value pairs is available since Redis v4.0.0. – Whiggism

Yes, sorry, updating the lib to redis-3.5.2 makes the warning in PyCharm go away. Now I don't know which answer to accept. Both are correct. I think for clarity I go with Ersoy. Thanks both. – Planetary

i will upvote @hmm then for more updated one :) - you are welcome Houman. – Whiggism

Answer 1

You may execute multiple hset for each field/value pair in hmset.

r.hset('myKey', 'users', 10)
r.hset('myKey', 'timestamp', datetime.utcnow().strftime('%Y-%m-%d %H:%M:%S'))
r.hset('myKey', 'yet-another-field', 'yet-another-value')

• first parameter is the key name
• second parameter is the field name
• third parameter is the value of the field.

Whiggism

This works but is not a good switch from hset to hmset using the same intended action - which is one call to set multiple fields - so this should not be the correct answer. – Laticialaticiferous

Answer 2

The problem is that you must specify within hset() that you are giving it the mapping. In your case:

r.hset("myKey", mapping=info)

instead of

r.hset("myKey", info)

Ikkela

This should be the correct answer - the goal of the question is to set multiple fields in one call - not how to set each field individually. – Laticialaticiferous

Answer 3

hmset(name, mapping): given a hash name ("myKey") and a dictionary (info) set all key/value pairs.

hset(name, key=None, value=None, mapping=None): given a hash name ("myKey") a key and a value, set the key/value. Alternatively, given a dictionary (mapping=info) set all key/value pairs in mapping.

Source: https://redis-py.readthedocs.io/en/stable/

If this does not work, perhaps you need to update the library?

Iliad

This is technically right but is less clear than the answer by David Cano. – Laticialaticiferous

Answer 4

I was using Redis.hmset() as following:

redis.hmset('myKey', info)

If you use Redis.hset() the following you will not get warning.

redis.hset('myKey', key=None, value=None, mapping=info)

With this usage, we will skip the single key & value adding step and redis.hset() will set all of the key and value mappings in info to myKey.

Asthenic