Raghav 8a4a7b25dc CLUSTERSCAN Command (#2934) ...

Implemented CLUSTERSCAN command for topology-aware scanning

Unlike `SCAN` which is local to a single node, `CLUSTERSCAN` provides a
mechanism that helps clients iterate across slot boundaries and handles
`MOVED` redirections.

**Key details**

* Global cluster iteration via `fingerprint-{hashtag}-cursor`
* Scan one slot at a time
* Start the CLUSTERSCAN with 0
* SLOT argument for parallel scanning of multiple slots
* Re-use scanGenericCommand for the response

**Cursor format:** `fingerprint-{hashtag}-localcursor`
 - Fingerprint is a hash of the node's DB seed that identifies the
   current memory layout. On mismatch, scan restarts from cursor 0
   rather than returning an error.
 - Fingerprint 0 indicates a cross slot cursor (e.g., initial cursor
   or slot transition) where validation is skipped.
 - Hashtag encodes the target slot
 - Local cursor tracks position within the slot

**Usage:**

```
CLUSTERSCAN <cursor> [MATCH pattern] [COUNT count] [TYPE type] [SLOT number]
```

```
  CLUSTERSCAN 0                    # Start scanning from slot 0
  CLUSTERSCAN <cursor>             # Continue from cursor
  CLUSTERSCAN 0 SLOT 1000          # Start scanning specific slot
  CLUSTERSCAN <cursor> MATCH user:* COUNT 100
```

---------

Signed-off-by: nmvk <r@nmvk.com>
Signed-off-by: Raghav <r@nmvk.com>
Signed-off-by: Madelyn Olson <madelyneolson@gmail.com>
Co-authored-by: Viktor Söderqvist <viktor.soderqvist@est.tech>
Co-authored-by: Madelyn Olson <madelyneolson@gmail.com>

2026-03-09 07:41:36 -07:00

..

format.yml

Format yaml files (#615)

2024-06-14 13:40:06 -07:00

typos.toml

CLUSTERSCAN Command (#2934)

2026-03-09 07:41:36 -07:00