feat: Add support for local Redis caching

README.md

@@ -30,6 +30,45 @@ Finally, set up your redis secrets based on instructions in `wrangler.toml`.
 
 Depending on your usage, you may try replacing Redis with [Cloudflare KV](https://developers.cloudflare.com/workers/runtime-apis/kv/) instead which is eventually consistent but will likely provide better read latency. Check `wrangler.toml` for setup instructions.
 
+### Caching with Local/Self-Hosted Redis
+
+In addition to Upstash Redis and Cloudflare KV, you can configure the proxy to use a local or self-hosted Redis instance for caching. This is useful for development or if you prefer to manage your own Redis server.
+
+**Configuration:**
+
+To use a local Redis instance, ensure that `UPSTASH_REDIS_REST_URL` and `UPSTASH_REDIS_REST_TOKEN` are **not** set. Then, configure the following environment variables:
+
+*   `LOCAL_REDIS_URL`: The hostname or IP address of your Redis server (e.g., `"127.0.0.1"`).
+*   `LOCAL_REDIS_PORT`: (Optional) The port number for your Redis server. Defaults to `6379` if not specified by `ioredis`.
+*   `LOCAL_REDIS_PASSWORD`: (Optional) The password for your Redis server, if it's password-protected.
+
+**Setting Environment Variables:**
+
+*   **For deployed workers:** Set these as secrets using Wrangler CLI or the Cloudflare dashboard:
+    ```bash
+    wrangler secret put LOCAL_REDIS_URL
+    # Enter your Redis host when prompted
+    wrangler secret put LOCAL_REDIS_PORT
+    # Enter your Redis port when prompted (optional)
+    wrangler secret put LOCAL_REDIS_PASSWORD
+    # Enter your Redis password when prompted (optional)
+    ```
+*   **For local development (`wrangler dev`):**
+    *   The recommended way is to create a `.dev.vars` file in your project root:
+        ```ini
+        LOCAL_REDIS_URL="127.0.0.1"
+        LOCAL_REDIS_PORT=6379
+        # LOCAL_REDIS_PASSWORD="yourpassword" # Uncomment if needed
+        ```
+    *   Alternatively, you can add them to the `[vars]` section in your `wrangler.toml` file (less common for local secrets).
+
+**Priority Order for Cache:**
+
+The worker will choose the caching mechanism based on the following priority:
+1.  Upstash Redis (if `UPSTASH_REDIS_REST_URL` and `UPSTASH_REDIS_REST_TOKEN` are set)
+2.  Local/Self-Hosted Redis (if `LOCAL_REDIS_URL` is set and Upstash is not)
+3.  Cloudflare KV (if `OPENAI_CACHE` is bound and neither Upstash nor Local Redis are configured)
+
 ### Usage
 
 Start the proxy server at http://localhost:8787 with: