feat: 处理 openai 格式请求

src/routes/openaiGeminiRoutes.js

@@ -3,7 +3,7 @@ const router = express.Router();
 const logger = require('../utils/logger');
 const { authenticateApiKey } = require('../middleware/auth');
 const geminiAccountService = require('../services/geminiAccountService');
-const { sendGeminiRequest, getAvailableModels } = require('../services/geminiRelayService');
+const { getAvailableModels } = require('../services/geminiRelayService');
 const crypto = require('crypto');
 
 // 生成会话哈希
@@ -23,6 +23,142 @@ function checkPermissions(apiKeyData, requiredPermission = 'gemini') {
   return permissions === 'all' || permissions === requiredPermission;
 }
 
+// 转换 OpenAI 消息格式到 Gemini 格式
+function convertMessagesToGemini(messages) {
+  const contents = [];
+  let systemInstruction = '';
+  
+  // 辅助函数：提取文本内容
+  function extractTextContent(content) {
+    // 处理 null 或 undefined
+    if (content == null) {
+      return '';
+    }
+    
+    // 处理字符串
+    if (typeof content === 'string') {
+      return content;
+    }
+    
+    // 处理数组格式的内容
+    if (Array.isArray(content)) {
+      return content.map(item => {
+        if (item == null) return '';
+        if (typeof item === 'string') {
+          return item;
+        }
+        if (typeof item === 'object') {
+          // 处理 {type: 'text', text: '...'} 格式
+          if (item.type === 'text' && item.text) {
+            return item.text;
+          }
+          // 处理 {text: '...'} 格式
+          if (item.text) {
+            return item.text;
+          }
+          // 处理嵌套的对象或数组
+          if (item.content) {
+            return extractTextContent(item.content);
+          }
+        }
+        return '';
+      }).join('');
+    }
+    
+    // 处理对象格式的内容
+    if (typeof content === 'object') {
+      // 处理 {text: '...'} 格式
+      if (content.text) {
+        return content.text;
+      }
+      // 处理 {content: '...'} 格式
+      if (content.content) {
+        return extractTextContent(content.content);
+      }
+      // 处理 {parts: [{text: '...'}]} 格式
+      if (content.parts && Array.isArray(content.parts)) {
+        return content.parts.map(part => {
+          if (part && part.text) {
+            return part.text;
+          }
+          return '';
+        }).join('');
+      }
+    }
+    
+    // 最后的后备选项：只有在内容确实不为空且有意义时才转换为字符串
+    if (content !== undefined && content !== null && content !== '' && typeof content !== 'object') {
+      return String(content);
+    }
+    
+    return '';
+  }
+  
+  for (const message of messages) {
+    const textContent = extractTextContent(message.content);
+    
+    if (message.role === 'system') {
+      systemInstruction += (systemInstruction ? '\n\n' : '') + textContent;
+    } else if (message.role === 'user') {
+      contents.push({
+        role: 'user',
+        parts: [{ text: textContent }]
+      });
+    } else if (message.role === 'assistant') {
+      contents.push({
+        role: 'model',
+        parts: [{ text: textContent }]
+      });
+    }
+  }
+  
+  return { contents, systemInstruction };
+}
+
+// 转换 Gemini 响应到 OpenAI 格式
+function convertGeminiResponseToOpenAI(geminiResponse, model, stream = false) {
+  if (stream) {
+    // 处理流式响应 - 原样返回 SSE 数据
+    return geminiResponse;
+  } else {
+    // 非流式响应转换
+    if (geminiResponse.candidates && geminiResponse.candidates.length > 0) {
+      const candidate = geminiResponse.candidates[0];
+      const content = candidate.content?.parts?.[0]?.text || '';
+      const finishReason = candidate.finishReason?.toLowerCase() || 'stop';
+
+      // 计算 token 使用量
+      const usage = geminiResponse.usageMetadata || {
+        promptTokenCount: 0,
+        candidatesTokenCount: 0,
+        totalTokenCount: 0
+      };
+
+      return {
+        id: `chatcmpl-${Date.now()}`,
+        object: 'chat.completion',
+        created: Math.floor(Date.now() / 1000),
+        model: model,
+        choices: [{
+          index: 0,
+          message: {
+            role: 'assistant',
+            content: content
+          },
+          finish_reason: finishReason
+        }],
+        usage: {
+          prompt_tokens: usage.promptTokenCount,
+          completion_tokens: usage.candidatesTokenCount,
+          total_tokens: usage.totalTokenCount
+        }
+      };
+    } else {
+      throw new Error('No response from Gemini');
+    }
+  }
+}
+
 // OpenAI 兼容的聊天完成端点
 router.post('/v1/chat/completions', authenticateApiKey, async (req, res) => {
   const startTime = Date.now();
@@ -62,7 +198,7 @@ router.post('/v1/chat/completions', authenticateApiKey, async (req, res) => {
     // 提取请求参数
     const {
       messages: requestMessages,
-      contents,
+      contents: requestContents,
       model: bodyModel = 'gemini-2.0-flash-exp',
       temperature = 0.7,
       max_tokens = 4096,
@@ -74,8 +210,8 @@ router.post('/v1/chat/completions', authenticateApiKey, async (req, res) => {
 
     // 支持两种格式: OpenAI 的 messages 或 Gemini 的 contents
     let messages = requestMessages;
-    if (contents && Array.isArray(contents)) {
-      messages = contents;
+    if (requestContents && Array.isArray(requestContents)) {
+      messages = requestContents;
     }
 
     // 验证必需参数
@@ -102,6 +238,23 @@ router.post('/v1/chat/completions', authenticateApiKey, async (req, res) => {
       }
     }
     
+    // 转换消息格式
+    const { contents: geminiContents, systemInstruction } = convertMessagesToGemini(messages);
+    
+    // 构建 Gemini 请求体
+    const geminiRequestBody = {
+      contents: geminiContents,
+      generationConfig: {
+        temperature,
+        maxOutputTokens: max_tokens,
+        candidateCount: 1
+      }
+    };
+    
+    if (systemInstruction) {
+      geminiRequestBody.systemInstruction = { parts: [{ text: systemInstruction }] };
+    }
+    
     // 生成会话哈希用于粘性会话
     const sessionHash = generateSessionHash(req);
     
@@ -137,39 +290,141 @@ router.post('/v1/chat/completions', authenticateApiKey, async (req, res) => {
       }
     });
     
-    // 发送请求到 Gemini（已经返回 OpenAI 格式）
-    const geminiResponse = await sendGeminiRequest({
-      messages,
-      model,
-      temperature,
-      maxTokens: max_tokens,
-      stream,
-      accessToken: account.accessToken,
-      proxy: account.proxy,
-      apiKeyId: apiKeyData.id,
-      signal: abortController.signal,
-      projectId: account.projectId
-    });
+    // 获取OAuth客户端
+    const client = await geminiAccountService.getOauthClient(account.accessToken, account.refreshToken);
     
+    let project = 'verdant-wares-464411-k9';
     if (stream) {
+      // 流式响应
+      logger.info('StreamGenerateContent request', {
+        model: model,
+        projectId: account.projectId,
+        apiKeyId: apiKeyData.id
+      });
+      
+      const streamResponse = await geminiAccountService.generateContentStream(
+        client,
+        { model, request: geminiRequestBody },
+        null, // user_prompt_id
+        project || account.projectId,
+        apiKeyData.id, // 使用 API Key ID 作为 session ID
+        abortController.signal // 传递中止信号
+      );
+      
       // 设置流式响应头
       res.setHeader('Content-Type', 'text/event-stream');
       res.setHeader('Cache-Control', 'no-cache');
       res.setHeader('Connection', 'keep-alive');
       res.setHeader('X-Accel-Buffering', 'no');
       
-      // 流式传输响应
-      for await (const chunk of geminiResponse) {
-        if (abortController.signal.aborted) {
-          break;
-        }
-        res.write(chunk);
-      }
+      // 处理流式响应，转换为 OpenAI 格式
+      let buffer = '';
+      
+      streamResponse.on('data', (chunk) => {
+        try {
+          buffer += chunk.toString();
+          const lines = buffer.split('\n');
+          buffer = lines.pop() || ''; // 保留最后一个不完整的行
+          
+          for (const line of lines) {
+            if (!line.trim()) continue;
+            
+            // 处理 SSE 格式
+            let jsonData = line;
+            if (line.startsWith('data: ')) {
+              jsonData = line.substring(6).trim();
+            }
+            
+            if (!jsonData || jsonData === '[DONE]') continue;
+            
+            try {
+              const data = JSON.parse(jsonData);
+              
+              // 转换为 OpenAI 流式格式
+              if (data.candidates && data.candidates.length > 0) {
+                const candidate = data.candidates[0];
+                const content = candidate.content?.parts?.[0]?.text || '';
+                const finishReason = candidate.finishReason?.toLowerCase();
+                
+                const openaiChunk = {
+                  id: `chatcmpl-${Date.now()}`,
+                  object: 'chat.completion.chunk',
+                  created: Math.floor(Date.now() / 1000),
+                  model: model,
+                  choices: [{
+                    index: 0,
+                    delta: {
+                      content: content
+                    },
+                    finish_reason: finishReason === 'stop' ? 'stop' : null
+                  }]
+                };
+                
+                res.write(`data: ${JSON.stringify(openaiChunk)}\n\n`);
+                
+                // 如果结束了，发送最终的 [DONE]
+                if (finishReason === 'stop') {
+                  res.write('data: [DONE]\n\n');
+                }
+              }
+            } catch (e) {
+              logger.debug('Error parsing JSON line:', e.message);
+            }
+          }
+        } catch (error) {
+          logger.error('Stream processing error:', error);
+          if (!res.headersSent) {
+            res.status(500).json({
+              error: {
+                message: error.message || 'Stream error',
+                type: 'api_error'
+              }
+            });
+          }
+        }
+      });
+      
+      streamResponse.on('end', () => {
+        logger.info('Stream completed successfully');
+        if (!res.headersSent) {
+          res.write('data: [DONE]\n\n');
+        }
+        res.end();
+      });
+      
+      streamResponse.on('error', (error) => {
+        logger.error('Stream error:', error);
+        if (!res.headersSent) {
+          res.status(500).json({
+            error: {
+              message: error.message || 'Stream error',
+              type: 'api_error'
+            }
+          });
+        } else {
+          res.end();
+        }
+      });
       
-      res.end();
     } else {
       // 非流式响应
-      res.json(geminiResponse);
+      logger.info('GenerateContent request', {
+        model: model,
+        projectId: account.projectId,
+        apiKeyId: apiKeyData.id
+      });
+      
+      const response = await geminiAccountService.generateContent(
+        client,
+        { model, request: geminiRequestBody },
+        null, // user_prompt_id
+        account.projectId,
+        apiKeyData.id // 使用 API Key ID 作为 session ID
+      );
+      
+      // 转换为 OpenAI 格式并返回
+      const openaiResponse = convertGeminiResponseToOpenAI(response, model, false);
+      res.json(openaiResponse);
     }
     
     const duration = Date.now() - startTime;