feat: Add LLM configuration support with environment variable fallback

- Updated `.env.example` with new LLM configuration variables
- Modified `LiteLLMClient` to support API key and base URL from environment variables
- Enhanced client initialization to use env vars with optional parameter overrides
- Added comprehensive test case for environment variable configuration

.env.example

@@ -15,6 +15,8 @@ BUSTER_WH_TOKEN="buster-wh-token"
 EMBEDDING_PROVIDER="ollama"
 EMBEDDING_MODEL="mxbai-embed-large"
 COHERE_API_KEY=""
+LLM_API_KEY="test-key"
+LLM_BASE_URL="http://localhost:8000"
 
 
 

api/src/utils/clients/ai/litellm/client.rs

@@ -2,6 +2,7 @@ use reqwest::{Client, header};
 use futures_util::StreamExt;
 use tokio::sync::mpsc;
 use anyhow::Result;
+use std::env;
 
 use super::types::*;
 
@@ -12,7 +13,15 @@ pub struct LiteLLMClient {
 }
 
 impl LiteLLMClient {
-    pub fn new(api_key: String, base_url: Option<String>) -> Self {
+    pub fn new(api_key: Option<String>, base_url: Option<String>) -> Self {
+        let api_key = api_key
+            .or_else(|| env::var("LLM_API_KEY").ok())
+            .expect("LLM_API_KEY must be provided either through parameter or environment variable");
+
+        let base_url = base_url
+            .or_else(|| env::var("LLM_BASE_URL").ok())
+            .unwrap_or_else(|| "http://localhost:8000".to_string());
+
         let mut headers = header::HeaderMap::new();
         headers.insert(
             "Authorization",
@@ -35,7 +44,7 @@ impl LiteLLMClient {
         Self {
             client,
             api_key,
-            base_url: base_url.unwrap_or_else(|| "http://localhost:8000".to_string()),
+            base_url,
         }
     }
 
@@ -110,6 +119,7 @@ mod tests {
     use mockito;
     use tokio::time::timeout;
     use std::time::Duration;
+    use std::env;
 
     fn create_test_message() -> Message {
         Message {
@@ -166,7 +176,7 @@ mod tests {
             .create();
 
         let client = LiteLLMClient::new(
-            "test-key".to_string(),
+            Some("test-key".to_string()),
             Some(server.url()),
         );
 
@@ -194,7 +204,7 @@ mod tests {
             .create();
 
         let client = LiteLLMClient::new(
-            "test-key".to_string(),
+            Some("test-key".to_string()),
             Some(server.url()),
         );
 
@@ -226,7 +236,7 @@ mod tests {
             .create();
 
         let client = LiteLLMClient::new(
-            "test-key".to_string(),
+            Some("test-key".to_string()),
             Some(server.url()),
         );
 
@@ -247,15 +257,26 @@ mod tests {
     }
 
     #[test]
-    fn test_client_initialization() {
-        let api_key = "test-key".to_string();
-        let base_url = "http://custom.url".to_string();
+    fn test_client_initialization_with_env_vars() {
+        let test_api_key = "test-env-key";
+        let test_base_url = "http://test-env-url";
         
-        let client = LiteLLMClient::new(api_key.clone(), Some(base_url.clone()));
-        assert_eq!(client.api_key, api_key);
-        assert_eq!(client.base_url, base_url);
-
-        let client = LiteLLMClient::new(api_key.clone(), None);
-        assert_eq!(client.base_url, "http://localhost:8000");
+        env::set_var("LLM_API_KEY", test_api_key);
+        env::set_var("LLM_BASE_URL", test_base_url);
+        
+        // Test with no parameters (should use env vars)
+        let client = LiteLLMClient::new(None, None);
+        assert_eq!(client.api_key, test_api_key);
+        assert_eq!(client.base_url, test_base_url);
+        
+        // Test with parameters (should override env vars)
+        let override_key = "override-key";
+        let override_url = "http://override-url";
+        let client = LiteLLMClient::new(Some(override_key.to_string()), Some(override_url.to_string()));
+        assert_eq!(client.api_key, override_key);
+        assert_eq!(client.base_url, override_url);
+        
+        env::remove_var("LLM_API_KEY");
+        env::remove_var("LLM_BASE_URL");
     }
 }