Unverified Commit 7b9e9606 authored by debing.sun's avatar debing.sun Committed by GitHub
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Hash Field Expiration (#13303)

## Background

This PR introduces support for field-level expiration in Redis hashes. Previously, Redis supported expiration only at the key level, but this enhancement allows setting expiration times for individual fields within a hash.

## New commands
* HEXPIRE
* HEXPIREAT
* HEXPIRETIME
* HPERSIST
* HPEXPIRE
* HPEXPIREAT
* HPEXPIRETIME
* HPTTL
* HTTL

## Short example
from @moticless
```sh
127.0.0.1:6379>  hset myhash f1 v1 f2 v2 f3 v3                                                   
(integer) 3
127.0.0.1:6379>  hpexpire myhash 10000 NX fields 2 f2 f3                                         
1) (integer) 1
2) (integer) 1
127.0.0.1:6379>  hpttl myhash fields 3 f1 f2 f3                                                                                                                                                                         
1) (integer) -1
2) (integer) 9997
3) (integer) 9997
127.0.0.1:6379>  hgetall myhash  
1) "f3"
2) "v3"
3) "f2"
4) "v2"
5) "f1"
6) "v1"

... after 10 seconds ...

127.0.0.1:6379>  hgetall myhash  
1) "f1"
2) "v1"
127.0.0.1:6379>
```

## Expiration strategy
1. Integrate active
    Redis periodically performs active expiration and deletion of hash keys that contain expired fields, with a maximum attempt limit.
3. Lazy expiration
    When a client touches fields within a hash, Redis checks if the fields are expired. If a field is expired, it will be deleted. However, we do not delete expired fields during a traversal, we implicitly skip over them.

## RDB changes
Add two new rdb type s`RDB_TYPE_HASH_METADATA` and `RDB_TYPE_HASH_LISTPACK_EX`.

## Notification
1. Add `hpersist` notification for `HPERSIST` command.
5. Add `hexpire` notification for `HEXPIRE`, `HEXPIREAT`, `HPEXPIRE` and `HPEXPIREAT` commands.

## Internal
1. Add new data structure `ebuckets`, which is used to store TTL and keys, enabling quick retrieval of keys based on TTL.
2. Add new data structure `mstr` like sds, which is used to store a string with TTL.

This work was done by @moticless, @tezc, @ronen-kalish, @sundb, I just release it.
parents 2d1bb42c f0389f28
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...@@ -34,6 +34,7 @@ set ::all_tests { ...@@ -34,6 +34,7 @@ set ::all_tests {
unit/type/set unit/type/set
unit/type/zset unit/type/zset
unit/type/hash unit/type/hash
unit/type/hash-field-expire
unit/type/stream unit/type/stream
unit/type/stream-cgroups unit/type/stream-cgroups
unit/sort unit/sort
......
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