[router] add grpc pd and regular router init (#9893)

sgl-router/src/config/validation.rs

@@ -349,6 +349,16 @@ impl ConfigValidator {
             return Ok(());
         }
 
+        // Validate gRPC connection mode requires tokenizer configuration
+        if config.connection_mode == ConnectionMode::Grpc
+            && config.tokenizer_path.is_none()
+            && config.model_path.is_none()
+        {
+            return Err(ConfigError::ValidationFailed {
+                reason: "gRPC connection mode requires either --tokenizer-path or --model-path to be specified".to_string(),
+            });
+        }
+
         // All policies are now supported for both router types thanks to the unified trait design
         // No mode/policy restrictions needed anymore
 
@@ -419,11 +429,14 @@ impl ConfigValidator {
                 });
             }
 
-            if !url.starts_with("http://") && !url.starts_with("https://") {
+            if !url.starts_with("http://")
+                && !url.starts_with("https://")
+                && !url.starts_with("grpc://")
+            {
                 return Err(ConfigError::InvalidValue {
                     field: "worker_url".to_string(),
                     value: url.clone(),
-                    reason: "URL must start with http:// or https://".to_string(),
+                    reason: "URL must start with http://, https://, or grpc://".to_string(),
                 });
             }
 
@@ -684,4 +697,60 @@ mod tests {
             assert!(e.to_string().contains("prefill requires at least 2"));
         }
     }
+
+    #[test]
+    fn test_validate_grpc_requires_tokenizer() {
+        // Test that gRPC connection mode requires tokenizer configuration
+        let mut config = RouterConfig::new(
+            RoutingMode::Regular {
+                worker_urls: vec!["grpc://worker:50051".to_string()],
+            },
+            PolicyConfig::Random,
+        );
+
+        // Set connection mode to gRPC without tokenizer config
+        config.connection_mode = ConnectionMode::Grpc;
+        config.tokenizer_path = None;
+        config.model_path = None;
+
+        let result = ConfigValidator::validate(&config);
+        assert!(result.is_err());
+        if let Err(e) = result {
+            assert!(e.to_string().contains("gRPC connection mode requires"));
+        }
+    }
+
+    #[test]
+    fn test_validate_grpc_with_model_path() {
+        // Test that gRPC works with model_path
+        let mut config = RouterConfig::new(
+            RoutingMode::Regular {
+                worker_urls: vec!["grpc://worker:50051".to_string()],
+            },
+            PolicyConfig::Random,
+        );
+
+        config.connection_mode = ConnectionMode::Grpc;
+        config.model_path = Some("meta-llama/Llama-3-8B".to_string());
+
+        let result = ConfigValidator::validate(&config);
+        assert!(result.is_ok());
+    }
+
+    #[test]
+    fn test_validate_grpc_with_tokenizer_path() {
+        // Test that gRPC works with tokenizer_path
+        let mut config = RouterConfig::new(
+            RoutingMode::Regular {
+                worker_urls: vec!["grpc://worker:50051".to_string()],
+            },
+            PolicyConfig::Random,
+        );
+
+        config.connection_mode = ConnectionMode::Grpc;
+        config.tokenizer_path = Some("/path/to/tokenizer.json".to_string());
+
+        let result = ConfigValidator::validate(&config);
+        assert!(result.is_ok());
+    }
 }