# LaunchDarkly Server-side SDK for Rust - Redis integration with redis client

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This library provides a [Redis](https://redis.io/)-backed persistence mechanism (data store) for the [LaunchDarkly Rust SDK](https://github.com/launchdarkly/rust-server-sdk), replacing the default in-memory data store.

The Redis API implementation it uses is [redis](https://crates.io/crates/redis). There are other Redis client implementations for Rust; if LaunchDarkly SDK Redis integrations using other Redis clients are released, they will be in separate repositories.

For more information, see also: [Using a persistent feature store](https://docs.launchdarkly.com/v2.0/docs/using-a-persistent-feature-store).

## LaunchDarkly overview

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## Quick setup

This assumes that you have already installed the LaunchDarkly Rust SDK.

1. Import the LaunchDarkly SDK packages and the package for this library:

```rust
use launchdarkly_server_sdk::{Client, ConfigBuilder, PersistentDataStoreBuilder};
use launchdarkly_server_sdk_redis::RedisPersistentDataStoreFactory;
use std::sync::Arc;
```

2. When configuring your SDK client, provide the `ConfigBuilder` with an instance of the `PersistentDataStoreBuilder`. You may specify any custom Redis options using the methods of `RedisPersistentDataStoreFactory`. For instance, to customize the Redis URL:

```rust
let mut redis_factory = RedisPersistentDataStoreFactory::new();
redis_factory.url("redis://localhost:9000");
let persistent_data_store_builder = PersistentDataStoreBuilder::new(Arc::new(redis_factory));

let mut config_builder = ConfigBuilder::new(&sdk_key);
config_builder = config_builder.data_store(&persistent_data_store_builder);
```

By default, the store will try to connect to a local Redis instance on port 6379.

## Caching behavior

The LaunchDarkly SDK has a standard caching mechanism for any persistent data store, to reduce database traffic. This is configured through the SDK's `PersistentDataStoreBuilder` class as described in the SDK documentation. For instance, to specify a cache TTL of 5 minutes:

```rust
let mut persistent_data_store_builder =
    PersistentDataStoreBuilder::new(Arc::new(redis_factory));
persistent_data_store_builder.cache_time(std::time::Duration::from_secs(5 * 60));
```

## About LaunchDarkly

* LaunchDarkly is a continuous delivery platform that provides feature flags as a service and allows developers to iterate quickly and safely. We allow you to easily flag your features and manage them from the LaunchDarkly dashboard.  With LaunchDarkly, you can:
    * Roll out a new feature to a subset of your users (like a group of users who opt-in to a beta tester group), gathering feedback and bug reports from real-world use cases.
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* Explore LaunchDarkly
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