🔧 refactor(helpers): 使用fake_useragent重构browser headers生成逻辑

app/models/schemas.py

@@ -8,12 +8,14 @@ from pydantic import BaseModel
 
 class ContentPart(BaseModel):
     """Content part model for OpenAI's new content format"""
+
     type: str
     text: Optional[str] = None
 
 
 class Message(BaseModel):
     """Chat message model"""
+
     role: str
     content: Optional[Union[str, List[ContentPart]]] = None
     reasoning_content: Optional[str] = None
@@ -22,6 +24,7 @@ class Message(BaseModel):
 
 class OpenAIRequest(BaseModel):
     """OpenAI-compatible request model"""
+
     model: str
     messages: List[Message]
     stream: Optional[bool] = False
@@ -33,6 +36,7 @@ class OpenAIRequest(BaseModel):
 
 class ModelItem(BaseModel):
     """Model information item"""
+
     id: str
     name: str
     owned_by: str
@@ -40,6 +44,7 @@ class ModelItem(BaseModel):
 
 class UpstreamRequest(BaseModel):
     """Upstream service request model"""
+
     stream: bool
     model: str
     messages: List[Message]
@@ -52,19 +57,21 @@ class UpstreamRequest(BaseModel):
     model_item: Optional[ModelItem] = None
     tool_servers: Optional[List[str]] = None
     variables: Optional[Dict[str, str]] = None
-    model_config = {'protected_namespaces': ()}
+    model_config = {"protected_namespaces": ()}
 
 
 class Delta(BaseModel):
     """Stream delta model"""
+
     role: Optional[str] = None
-    content: Optional[str] = None
+    content: Optional[str] = "" or None
     reasoning_content: Optional[str] = None
     tool_calls: Optional[List[Dict[str, Any]]] = None
 
 
 class Choice(BaseModel):
     """Response choice model"""
+
     index: int
     message: Optional[Message] = None
     delta: Optional[Delta] = None
@@ -73,6 +80,7 @@ class Choice(BaseModel):
 
 class Usage(BaseModel):
     """Token usage statistics"""
+
     prompt_tokens: int = 0
     completion_tokens: int = 0
     total_tokens: int = 0
@@ -80,6 +88,7 @@ class Usage(BaseModel):
 
 class OpenAIResponse(BaseModel):
     """OpenAI-compatible response model"""
+
     id: str
     object: str
     created: int
@@ -90,17 +99,20 @@ class OpenAIResponse(BaseModel):
 
 class UpstreamError(BaseModel):
     """Upstream error model"""
+
     detail: str
     code: int
 
 
 class UpstreamDataInner(BaseModel):
     """Inner upstream data model"""
+
     error: Optional[UpstreamError] = None
 
 
 class UpstreamDataData(BaseModel):
     """Upstream data content model"""
+
     delta_content: str = ""
     edit_content: str = ""
     phase: str = ""
@@ -112,6 +124,7 @@ class UpstreamDataData(BaseModel):
 
 class UpstreamData(BaseModel):
     """Upstream data model"""
+
     type: str
     data: UpstreamDataData
     error: Optional[UpstreamError] = None
@@ -119,6 +132,7 @@ class UpstreamData(BaseModel):
 
 class Model(BaseModel):
     """Model information for listing"""
+
     id: str
     object: str = "model"
     created: int
@@ -127,7 +141,6 @@ class Model(BaseModel):
 
 class ModelsResponse(BaseModel):
     """Models list response model"""
+
     object: str = "list"
     data: List[Model]
-
-

app/utils/helpers.py

@@ -5,11 +5,23 @@ Utility functions for the application
 import json
 import re
 import time
+import random
 from typing import Dict, List, Optional, Any, Tuple, Generator
 import requests
+from fake_useragent import UserAgent
 
 from app.core.config import settings
 
+# 全局 UserAgent 实例，避免每次调用都创建新实例
+_user_agent_instance = None
+
+def get_user_agent_instance() -> UserAgent:
+    """获取或创建 UserAgent 实例（单例模式）"""
+    global _user_agent_instance
+    if _user_agent_instance is None:
+        _user_agent_instance = UserAgent()
+    return _user_agent_instance
+
 
 def debug_log(message: str, *args) -> None:
     """Log debug message if debug mode is enabled"""
@@ -29,12 +41,84 @@ def generate_request_ids() -> Tuple[str, str]:
 
 
 def get_browser_headers(referer_chat_id: str = "") -> Dict[str, str]:
-    """Get browser headers for API requests"""
-    headers = settings.CLIENT_HEADERS.copy()
+    """Get browser headers for API requests with dynamic User-Agent"""
+    
+    # 获取 UserAgent 实例
+    ua = get_user_agent_instance()
+    
+    # 随机选择一个浏览器类型，偏向使用 Chrome 和 Edge
+    browser_choices = ['chrome', 'chrome', 'chrome', 'edge', 'edge', 'firefox', 'safari']
+    browser_type = random.choice(browser_choices)
+    
+    try:
+        # 根据浏览器类型获取 User-Agent
+        if browser_type == 'chrome':
+            user_agent = ua.chrome
+        elif browser_type == 'edge':
+            user_agent = ua.edge
+        elif browser_type == 'firefox':
+            user_agent = ua.firefox
+        elif browser_type == 'safari':
+            user_agent = ua.safari
+        else:
+            user_agent = ua.random
+    except:
+        # 如果获取失败，使用随机 User-Agent
+        user_agent = ua.random
+    
+    # 提取浏览器版本信息
+    chrome_version = "139"  # 默认版本
+    edge_version = "139"
     
+    if "Chrome/" in user_agent:
+        try:
+            chrome_version = user_agent.split("Chrome/")[1].split(".")[0]
+        except:
+            pass
+    
+    if "Edg/" in user_agent:
+        try:
+            edge_version = user_agent.split("Edg/")[1].split(".")[0]
+            # Edge 基于 Chromium，使用 Edge 特定的 sec-ch-ua
+            sec_ch_ua = f'"Microsoft Edge";v="{edge_version}", "Chromium";v="{chrome_version}", "Not_A Brand";v="24"'
+        except:
+            sec_ch_ua = f'"Not_A Brand";v="8", "Chromium";v="{chrome_version}", "Google Chrome";v="{chrome_version}"'
+    elif "Firefox/" in user_agent:
+        # Firefox 不使用 sec-ch-ua
+        sec_ch_ua = None
+    else:
+        # Chrome 或其他基于 Chromium 的浏览器
+        sec_ch_ua = f'"Not_A Brand";v="8", "Chromium";v="{chrome_version}", "Google Chrome";v="{chrome_version}"'
+    
+    # 构建动态 Headers
+    headers = {
+        "Content-Type": "application/json",
+        "Accept": "application/json, text/event-stream",
+        "User-Agent": user_agent,
+        "Accept-Language": "zh-CN,zh;q=0.9,en;q=0.8,en-US;q=0.7",
+        "sec-ch-ua-mobile": "?0",
+        "sec-ch-ua-platform": '"Windows"',
+        "sec-fetch-dest": "empty",
+        "sec-fetch-mode": "cors",
+        "sec-fetch-site": "same-origin",
+        "X-FE-Version": "prod-fe-1.0.70",
+        "Origin": settings.CLIENT_HEADERS["Origin"],
+        "Cache-Control": "no-cache",
+        "Pragma": "no-cache",
+    }
+    
+    # 只有基于 Chromium 的浏览器才添加 sec-ch-ua
+    if sec_ch_ua:
+        headers["sec-ch-ua"] = sec_ch_ua
+    
+    # 添加 Referer
     if referer_chat_id:
         headers["Referer"] = f"{settings.CLIENT_HEADERS['Origin']}/c/{referer_chat_id}"
     
+    # 调试日志
+    if settings.DEBUG_LOGGING:
+        debug_log(f"使用 User-Agent: {user_agent[:100]}...")
+    
     return headers