[model-gateway] move oai header util to router header util (#14441)

Co-authored-by: key4ng <rukeyang@gmail.com>

sgl-router/src/routers/header_utils.rs

@@ -1,4 +1,8 @@
-use axum::{body::Body, extract::Request, http::HeaderMap};
+use axum::{
+    body::Body,
+    extract::Request,
+    http::{HeaderMap, HeaderValue},
+};
 
 /// Copy request headers to a Vec of name-value string pairs
 /// Used for forwarding headers to backend workers
@@ -92,3 +96,89 @@ pub fn apply_request_headers(
 
     request_builder
 }
+
+/// API provider types for provider-specific header handling
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum ApiProvider {
+    Anthropic,
+    Xai,
+    OpenAi,
+    Gemini,
+    Generic,
+}
+
+impl ApiProvider {
+    /// Detect provider type from URL
+    pub fn from_url(url: &str) -> Self {
+        if url.contains("anthropic") {
+            ApiProvider::Anthropic
+        } else if url.contains("x.ai") {
+            ApiProvider::Xai
+        } else if url.contains("openai.com") {
+            ApiProvider::OpenAi
+        } else if url.contains("googleapis.com") {
+            ApiProvider::Gemini
+        } else {
+            ApiProvider::Generic
+        }
+    }
+}
+
+/// Apply provider-specific headers to request
+pub fn apply_provider_headers(
+    mut req: reqwest::RequestBuilder,
+    url: &str,
+    auth_header: Option<&HeaderValue>,
+) -> reqwest::RequestBuilder {
+    let provider = ApiProvider::from_url(url);
+
+    match provider {
+        ApiProvider::Anthropic => {
+            // Anthropic requires x-api-key instead of Authorization
+            // Extract Bearer token and use as x-api-key
+            if let Some(auth) = auth_header {
+                if let Ok(auth_str) = auth.to_str() {
+                    let api_key = auth_str.strip_prefix("Bearer ").unwrap_or(auth_str);
+                    req = req
+                        .header("x-api-key", api_key)
+                        .header("anthropic-version", "2023-06-01");
+                }
+            }
+        }
+        ApiProvider::Gemini | ApiProvider::Xai | ApiProvider::OpenAi | ApiProvider::Generic => {
+            // Standard OpenAI-compatible: use Authorization header as-is
+            if let Some(auth) = auth_header {
+                req = req.header("Authorization", auth);
+            }
+        }
+    }
+
+    req
+}
+
+/// Extract auth header with passthrough semantics.
+///
+/// Passthrough mode: User's Authorization header takes priority.
+/// Fallback: Worker's API key is used only if user didn't provide auth.
+///
+/// This enables use cases where:
+/// 1. Users send their own API keys (multi-tenant, BYOK)
+/// 2. Router has a default key for users who don't provide one
+pub fn extract_auth_header(
+    headers: Option<&HeaderMap>,
+    worker_api_key: &Option<String>,
+) -> Option<HeaderValue> {
+    // Passthrough: Try user's auth header first
+    let user_auth = headers.and_then(|h| {
+        h.get("authorization")
+            .or_else(|| h.get("Authorization"))
+            .cloned()
+    });
+
+    // Return user's auth if provided, otherwise use worker's API key
+    user_auth.or_else(|| {
+        worker_api_key
+            .as_ref()
+            .and_then(|k| HeaderValue::from_str(&format!("Bearer {}", k)).ok())
+    })
+}

sgl-router/src/routers/openai/conversations.rs

@@ -22,10 +22,6 @@ use crate::{
     protocols::responses::{generate_id, ResponseInput, ResponsesRequest},
 };
 
-// ============================================================================
-// Persistence Operations (OpenAI-specific)
-// ============================================================================
-
 /// Persist conversation items to storage
 ///
 /// This function:

sgl-router/src/routers/openai/router.rs

@@ -30,7 +30,6 @@ use super::{
     provider::ProviderRegistry,
     responses::{mask_tools_as_mcp, patch_streaming_response_json},
     streaming::handle_streaming_response,
-    utils::{apply_provider_headers, extract_auth_header},
 };
 use crate::{
     app_context::AppContext,
@@ -48,6 +47,7 @@ use crate::{
             ResponsesGetParams, ResponsesRequest,
         },
     },
+    routers::header_utils::{apply_provider_headers, extract_auth_header},
 };
 
 pub struct OpenAIRouter {

sgl-router/src/routers/openai/utils.rs

@@ -2,8 +2,6 @@
 
 use std::collections::HashMap;
 
-use axum::http::HeaderValue;
-
 // ============================================================================
 // SSE Event Type Constants
 // ============================================================================
@@ -95,100 +93,6 @@ impl OutputIndexMapper {
     }
 }
 
-// ============================================================================
-// Provider Detection and Header Handling
-// ============================================================================
-
-/// API provider types
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
-pub enum ApiProvider {
-    Anthropic,
-    Xai,
-    OpenAi,
-    Gemini,
-    Generic,
-}
-
-impl ApiProvider {
-    /// Detect provider type from URL
-    pub fn from_url(url: &str) -> Self {
-        if url.contains("anthropic") {
-            ApiProvider::Anthropic
-        } else if url.contains("x.ai") {
-            ApiProvider::Xai
-        } else if url.contains("openai.com") {
-            ApiProvider::OpenAi
-        } else if url.contains("googleapis.com") {
-            ApiProvider::Gemini
-        } else {
-            ApiProvider::Generic
-        }
-    }
-}
-
-/// Apply provider-specific headers to request
-pub fn apply_provider_headers(
-    mut req: reqwest::RequestBuilder,
-    url: &str,
-    auth_header: Option<&HeaderValue>,
-) -> reqwest::RequestBuilder {
-    let provider = ApiProvider::from_url(url);
-
-    match provider {
-        ApiProvider::Anthropic => {
-            // Anthropic requires x-api-key instead of Authorization
-            // Extract Bearer token and use as x-api-key
-            if let Some(auth) = auth_header {
-                if let Ok(auth_str) = auth.to_str() {
-                    let api_key = auth_str.strip_prefix("Bearer ").unwrap_or(auth_str);
-                    req = req
-                        .header("x-api-key", api_key)
-                        .header("anthropic-version", "2023-06-01");
-                }
-            }
-        }
-        ApiProvider::Gemini | ApiProvider::Xai | ApiProvider::OpenAi | ApiProvider::Generic => {
-            // Standard OpenAI-compatible: use Authorization header as-is
-            if let Some(auth) = auth_header {
-                req = req.header("Authorization", auth);
-            }
-        }
-    }
-
-    req
-}
-
-// ============================================================================
-// Auth Header Resolution
-// ============================================================================
-
-/// Extract auth header with passthrough semantics.
-///
-/// Passthrough mode: User's Authorization header takes priority.
-/// Fallback: Worker's API key is used only if user didn't provide auth.
-///
-/// This enables use cases where:
-/// 1. Users send their own API keys (multi-tenant, BYOK)
-/// 2. Router has a default key for users who don't provide one
-pub fn extract_auth_header(
-    headers: Option<&http::HeaderMap>,
-    worker_api_key: &Option<String>,
-) -> Option<HeaderValue> {
-    // Passthrough: Try user's auth header first
-    let user_auth = headers.and_then(|h| {
-        h.get("authorization")
-            .or_else(|| h.get("Authorization"))
-            .cloned()
-    });
-
-    // Return user's auth if provided, otherwise use worker's API key
-    user_auth.or_else(|| {
-        worker_api_key
-            .as_ref()
-            .and_then(|k| HeaderValue::from_str(&format!("Bearer {}", k)).ok())
-    })
-}
-
 // ============================================================================
 // Re-export FunctionCallInProgress from mcp module
 // ============================================================================