> ## Documentation Index
> Fetch the complete documentation index at: https://docs.prefect.io/llms.txt
> Use this file to discover all available pages before exploring further.

# prefect-redis

Integrations to extend Prefect's functionality with Redis.

## Getting started

### Install `prefect-redis`

The following command will install a version of `prefect-redis` compatible with your installed version of `prefect`.
If you don't already have `prefect` installed, it will install the newest version of `prefect` as well.

```bash theme={null}
pip install "prefect[redis]"
```

Upgrade to the latest versions of `prefect` and `prefect-redis`:

```bash theme={null}
pip install -U "prefect[redis]"
```

### Register newly installed block types

Register the block types in the `prefect-redis` module to make them available for use.

```bash theme={null}
prefect block register -m prefect_redis
```

## Connecting with a URL (including Redis Sentinel)

Every `prefect-redis` connection point — the server messaging client, the worker
cleanup queue, the `RedisLockManager`, and the `RedisDatabase` block — accepts a full
connection URL in addition to the individual `host`/`port`/`db`/`username`/`password`/`ssl`
fields. When a URL is provided it is authoritative and the scalar fields are ignored.

The following schemes are supported:

| Scheme               | Behavior                                                                                                             |
| -------------------- | -------------------------------------------------------------------------------------------------------------------- |
| `redis://`           | Single-node TCP connection                                                                                           |
| `rediss://`          | Single-node TLS connection                                                                                           |
| `redis+sentinel://`  | [Redis Sentinel](https://redis.io/docs/latest/operate/oss_and_stack/management/sentinel/) discovery (TCP data nodes) |
| `rediss+sentinel://` | Redis Sentinel discovery (TLS data nodes)                                                                            |

The Sentinel schemes accept a comma-separated list of Sentinel members and a master
group name, and the resulting client resolves the current master through the Sentinel
daemons and follows failover automatically:

```
redis+sentinel://[user:pass@]sentinel-a:26379,sentinel-b:26379/<master-name>[/<db>][?params]
```

The `sentinel_username` and `sentinel_password` query parameters configure
authentication to the Sentinel daemons separately from the data nodes. All other query
parameters are treated as standard [redis-py](https://redis-py.readthedocs.io/)
connection options (`socket_timeout`, `max_connections`, `health_check_interval`, ...)
and apply to the data-node connections. On the `rediss+sentinel://` scheme the `ssl_*`
options also apply to the Sentinel daemon connections, so a single private CA works
for the whole topology, e.g.
`rediss+sentinel://sentinel-a:26379,sentinel-b:26379/mymaster?ssl_ca_certs=/etc/redis/ca.pem`.
Query options take precedence over the equivalent Prefect settings (for example
`PREFECT_REDIS_MESSAGING_SOCKET_TIMEOUT`), just as they do with redis-py's
`Redis.from_url`.

### Server messaging and worker cleanup queue

Point the Prefect server's Redis messaging and its worker cleanup queue at a Sentinel
topology with one URL per subsystem:

```bash theme={null}
export PREFECT_REDIS_MESSAGING_URL="redis+sentinel://sentinel-a:26379,sentinel-b:26379/mymaster"
export PREFECT_REDIS_WORKER_CLEANUP_QUEUE_URL="redis+sentinel://sentinel-a:26379,sentinel-b:26379/mymaster"
```

Both settings also accept single-node `redis://` / `rediss://` URLs.

### Lock manager

```python theme={null}
from prefect_redis import RedisLockManager

lock_manager = RedisLockManager(
    connection_url="redis+sentinel://sentinel-a:26379,sentinel-b:26379/mymaster"
)
```

### `RedisDatabase` block

```python theme={null}
from prefect_redis import RedisDatabase

block = RedisDatabase.from_connection_string(
    "redis+sentinel://sentinel-a:26379,sentinel-b:26379/mymaster"
)
block.save("BLOCK_NAME")
```

## Resources

Refer to the [SDK documentation](/integrations/prefect-redis/api-ref/prefect_redis-blocks) to explore all the capabilities of `prefect-redis`.