Add manual routing policy for router (#15586)

sgl-model-gateway/src/protocols/chat.rs

@@ -359,6 +359,10 @@ pub struct ChatCompletionRequest {
     /// Random seed for sampling for deterministic outputs
     #[serde(skip_serializing_if = "Option::is_none")]
     pub sampling_seed: Option<u64>,
+
+    /// Routing ID for manual routing policy
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub routing_id: Option<String>,
 }
 
 // ============================================================================
@@ -696,6 +700,10 @@ impl GenerationRequest for ChatCompletionRequest {
 
         buffer
     }
+
+    fn get_routing_id(&self) -> Option<&str> {
+        self.routing_id.as_deref()
+    }
 }
 
 // ============================================================================

sgl-model-gateway/src/protocols/classify.rs

@@ -30,6 +30,10 @@ pub struct ClassifyRequest {
     /// SGLang extension: request id for tracking
     #[serde(skip_serializing_if = "Option::is_none")]
     pub rid: Option<String>,
+
+    /// Routing ID for manual routing policy
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub routing_id: Option<String>,
 }
 
 impl GenerationRequest for ClassifyRequest {
@@ -54,4 +58,8 @@ impl GenerationRequest for ClassifyRequest {
             _ => String::new(),
         }
     }
+
+    fn get_routing_id(&self) -> Option<&str> {
+        self.routing_id.as_deref()
+    }
 }

sgl-model-gateway/src/protocols/common.rs

@@ -36,6 +36,9 @@ pub trait GenerationRequest: Send + Sync {
 
     /// Extract text content for routing decisions
     fn extract_text_for_routing(&self) -> String;
+
+    /// Get routing ID for manual routing policy
+    fn get_routing_id(&self) -> Option<&str>;
 }
 
 // ============================================================================

sgl-model-gateway/src/protocols/completion.rs

@@ -145,6 +145,10 @@ pub struct CompletionRequest {
     /// Additional fields including bootstrap info for PD routing
     #[serde(flatten)]
     pub other: Map<String, Value>,
+
+    /// Routing ID for manual routing policy
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub routing_id: Option<String>,
 }
 
 impl GenerationRequest for CompletionRequest {
@@ -162,6 +166,10 @@ impl GenerationRequest for CompletionRequest {
             StringOrArray::Array(v) => v.join(" "),
         }
     }
+
+    fn get_routing_id(&self) -> Option<&str> {
+        self.routing_id.as_deref()
+    }
 }
 
 // ============================================================================

sgl-model-gateway/src/protocols/embedding.rs

@@ -31,6 +31,10 @@ pub struct EmbeddingRequest {
     #[serde(skip_serializing_if = "Option::is_none")]
     pub rid: Option<String>,
 
+    /// Routing ID for manual routing policy
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub routing_id: Option<String>,
+
     /// SGLang extension: enable/disable logging of metrics for this request
     #[serde(skip_serializing_if = "Option::is_none")]
     pub log_metrics: Option<bool>,
@@ -58,6 +62,10 @@ impl GenerationRequest for EmbeddingRequest {
             _ => String::new(),
         }
     }
+
+    fn get_routing_id(&self) -> Option<&str> {
+        self.routing_id.as_deref()
+    }
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]

sgl-model-gateway/src/protocols/generate.rs

@@ -167,6 +167,10 @@ pub struct GenerateRequest {
     /// Request ID for tracking (inherited from BaseReq in Python)
     #[serde(skip_serializing_if = "Option::is_none")]
     pub rid: Option<String>,
+
+    /// Routing ID for manual routing policy
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub routing_id: Option<String>,
 }
 
 impl Normalizable for GenerateRequest {
@@ -235,6 +239,10 @@ impl GenerationRequest for GenerateRequest {
         // No text input found
         String::new()
     }
+
+    fn get_routing_id(&self) -> Option<&str> {
+        self.routing_id.as_deref()
+    }
 }
 
 // ============================================================================

sgl-model-gateway/src/protocols/rerank.rs

@@ -52,6 +52,10 @@ pub struct RerankRequest {
 
     /// User identifier
     pub user: Option<String>,
+
+    /// Routing ID for manual routing policy
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub routing_id: Option<String>,
 }
 
 impl GenerationRequest for RerankRequest {
@@ -66,6 +70,10 @@ impl GenerationRequest for RerankRequest {
     fn extract_text_for_routing(&self) -> String {
         self.query.clone()
     }
+
+    fn get_routing_id(&self) -> Option<&str> {
+        self.routing_id.as_deref()
+    }
 }
 
 impl super::validated::Normalizable for RerankRequest {
@@ -207,6 +215,7 @@ impl From<V1RerankReqInput> for RerankRequest {
             return_documents: true,
             rid: None,
             user: None,
+            routing_id: None,
         }
     }
 }

sgl-model-gateway/src/protocols/responses.rs

@@ -616,6 +616,10 @@ pub struct ResponsesRequest {
     #[serde(default = "default_repetition_penalty")]
     #[validate(range(min = 0.0, max = 2.0))]
     pub repetition_penalty: f32,
+
+    /// Routing ID for manual routing policy
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub routing_id: Option<String>,
 }
 
 #[derive(Debug, Clone, Deserialize, Serialize)]
@@ -659,6 +663,7 @@ impl Default for ResponsesRequest {
             top_k: default_top_k(),
             min_p: 0.0,
             repetition_penalty: default_repetition_penalty(),
+            routing_id: None,
         }
     }
 }
@@ -770,6 +775,10 @@ impl GenerationRequest for ResponsesRequest {
                 .join(" "),
         }
     }
+
+    fn get_routing_id(&self) -> Option<&str> {
+        self.routing_id.as_deref()
+    }
 }
 
 /// Validate conversation ID format