feat: add driver context access in createVars function (#2841)

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## Changes

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Author: NathanFlurry

site/public/llms-full.txt

@@ -118,3 +118,35 @@ Use `state` when:
 
 - The data must be preserved across actor sleeps, restarts, updates, or crashes
 - The information is essential to the actor's core functionality and business logic
+
+## Advanced
+
+### Accessing Driver Context
+
+The `createVars` function receives a second parameter that provides access to driver-specific context. This allows you to access driver-specific functionality.
+
+For example, the Redis driver exposes access to the Redis instance:
+
+```typescript
+import { actor, ActorInitContext } from "@rivetkit/actor";
+import { DriverContext } from "@rivetkit/redis";
+
+const myActor = actor({
+  state: { count: 0 },
+  
+  // The second parameter provides driver-specific context
+  createVars: (ctx: ActorInitContext, driver: DriverContext) => ({ driver }),
+  
+  actions: {
+    accessDriverFeatures: (c) => {
+      // Access Redis
+      const redis = c.vars.driver.redis;
+	  const keyPrefix = c.vars.driver.keyPrefix;
+      // ...etc...
+    }
+  }
+});
+```
+
+Consult the documentation for each driver to learn more about their respective `DriverContext` types.
+

site/src/content/docs/actors/ephemeral-variables.mdx

@@ -129,3 +129,42 @@ Example using Redis driver with Hono web framework.
 Basic Redis driver setup and configuration example.
 </Card>
 </CardGroup>
+
+## Advanced
+
+### Driver Context
+
+The Redis driver provides access to the underlying Redis connection through the driver context in `createVars`.
+
+```typescript
+import { actor, ActorInitContext } from "@rivetkit/actor";
+import type { DriverContext } from "@rivetkit/redis";
+
+const myActor = actor({
+  state: { count: 0 },
+  
+  // Save the Redis driver context
+  createVars: (ctx: ActorInitContext, driver: DriverContext) => ({ redis: driver.redis }),
+  
+  actions: {
+    // Example: Access Redis directly (not recommended in practice)
+    getRedisValue: async (c, key: string) => {
+      // Use the Redis client from driver context
+      return await c.vars.redis.get(key);
+    },
+  }
+});
+```
+
+The Redis driver context type is exported as `DriverContext` from `@rivetkit/redis`:
+
+```typescript
+interface DriverContext {
+  redis: ioredis.Redis;
+  keyPrefix: string;  // Key prefix that all RivetKit data is stored under
+}
+```
+
+<Warning>
+While you have access to the Redis client, be cautious when directly modifying keys under the `keyPrefix`, as this may interfere with RivetKit's internal operations and potentially break actor functionality.
+</Warning>

site/src/content/docs/drivers/redis.mdx

@@ -141,3 +141,71 @@ Example using Cloudflare Workers with Hono web framework.
 Basic Cloudflare Workers setup and configuration example.
 </Card>
 </CardGroup>
+
+## Advanced
+
+### Accessing Environment Bindings
+
+You can access Cloudflare Workers environment bindings directly using the importable `env`:
+
+```typescript
+import { env } from "cloudflare:workers";
+
+// Access environment variables and secrets in top-level scope
+const API_KEY = env.API_KEY;
+const LOG_LEVEL = env.LOG_LEVEL || "info";
+
+// Use bindings in your actor
+const myActor = actor({
+  state: { count: 0 },
+  
+  actions: {
+    // Access KV, D1, or other bindings during request handling
+    getFromKV: async (c, key: string) => {
+      // Access additional KV namespaces defined in wrangler.json
+      if (env.MY_CACHE_KV) {
+        return await env.MY_CACHE_KV.get(key);
+      }
+    }
+  }
+});
+```
+
+### Driver Context
+
+The Cloudflare Workers driver provides access to the Durable Object state and environment through the driver context in `createVars`.
+
+```typescript
+import { actor, ActorInitContext } from "@rivetkit/actor";
+import type { DriverContext } from "@rivetkit/cloudflare-workers";
+
+const myActor = actor({
+  state: { count: 0 },
+  
+  // Save the Cloudflare driver context
+  createVars: (ctx: ActorInitContext, driver: DriverContext) => ({ 
+    state: driver.state,
+  }),
+  
+  actions: {
+    // Example: Access Durable Object info (not recommended in practice)
+    kvGet: (c, key: string) => {
+      const doState = c.vars.state;
+	  return await doState.storage.get(key)
+    },
+  }
+});
+```
+
+The Cloudflare Workers driver context type is exported as `DriverContext` from `@rivetkit/cloudflare-workers`:
+
+```typescript
+interface DriverContext {
+  state: DurableObjectState;
+}
+```
+
+<Warning>
+While you have access to the Durable Object state, be cautious when directly modifying KV storage or alarms, as this may interfere with RivetKit's internal operations and potentially break actor functionality.
+</Warning>
+