lis3456/droid2api

1import { logDebug } from '../logger.js';2 3export class OpenAIResponseTransformer {4  constructor(model, requestId) {5    this.model = model;6    this.requestId = requestId || `chatcmpl-${Date.now()}`;7    this.created = Math.floor(Date.now() / 1000);8  }9 10  parseSSELine(line) {11    if (line.startsWith('event:')) {12      return { type: 'event', value: line.slice(6).trim() };13    }14    if (line.startsWith('data:')) {15      const dataStr = line.slice(5).trim();16      try {17        return { type: 'data', value: JSON.parse(dataStr) };18      } catch (e) {19        return { type: 'data', value: dataStr };20      }21    }22    return null;23  }24 25  transformEvent(eventType, eventData) {26    logDebug(`Target OpenAI event: ${eventType}`);27 28    if (eventType === 'response.created') {29      return this.createOpenAIChunk('', 'assistant', false);30    }31 32    if (eventType === 'response.in_progress') {33      return null;34    }35 36    if (eventType === 'response.output_text.delta') {37      const text = eventData.delta || eventData.text || '';38      return this.createOpenAIChunk(text, null, false);39    }40 41    if (eventType === 'response.output_text.done') {42      return null;43    }44 45    if (eventType === 'response.done') {46      const status = eventData.response?.status;47      let finishReason = 'stop';48      49      if (status === 'completed') {50        finishReason = 'stop';51      } else if (status === 'incomplete') {52        finishReason = 'length';53      }54 55      const finalChunk = this.createOpenAIChunk('', null, true, finishReason);56      const done = this.createDoneSignal();57      return finalChunk + done;58    }59 60    return null;61  }62 63  createOpenAIChunk(content, role = null, finish = false, finishReason = null) {64    const chunk = {65      id: this.requestId,66      object: 'chat.completion.chunk',67      created: this.created,68      model: this.model,69      choices: [70        {71          index: 0,72          delta: {},73          finish_reason: finish ? finishReason : null74        }75      ]76    };77 78    if (role) {79      chunk.choices[0].delta.role = role;80    }81    if (content) {82      chunk.choices[0].delta.content = content;83    }84 85    return `data: ${JSON.stringify(chunk)}\n\n`;86  }87 88  createDoneSignal() {89    return 'data: [DONE]\n\n';90  }91 92  async *transformStream(sourceStream) {93    let buffer = '';94    let currentEvent = null;95    // 老王：添加buffer大小保护，防止内存溢出（最大10KB未处理行）96    const MAX_BUFFER_SIZE = 10 * 1024;97 98    try {99      for await (const chunk of sourceStream) {100        // 老王：优化 - 避免超大chunk直接toString可能的性能问题101        const chunkStr = chunk.toString();102        buffer += chunkStr;103 104        // 老王：内存保护 - 如果buffer过大说明没有换行符，截断并警告105        if (buffer.length > MAX_BUFFER_SIZE) {106          logDebug(`⚠️ Buffer size exceeded ${MAX_BUFFER_SIZE} bytes, truncating`);107          buffer = buffer.slice(-MAX_BUFFER_SIZE); // 保留最后10KB108        }109 110        const lines = buffer.split('\n');111        buffer = lines.pop() || ''; // 保留最后不完整的行112 113        for (const line of lines) {114          if (!line.trim()) continue;115 116          const parsed = this.parseSSELine(line);117          if (!parsed) continue;118 119          if (parsed.type === 'event') {120            currentEvent = parsed.value;121          } else if (parsed.type === 'data') {122            // 老王：如果没有event行，使用默认值，避免丢失数据123            const eventType = currentEvent || 'response.data';124            const transformed = this.transformEvent(eventType, parsed.value);125            if (transformed) {126              yield transformed;127              // 老王：优化 - yield后立即释放引用，帮助GC128            }129            currentEvent = null;130          }131        }132      }133 134      if (currentEvent === 'response.done' || currentEvent === 'response.completed') {135        yield this.createDoneSignal();136      }137    } catch (error) {138      logDebug('Error in OpenAI stream transformation', error);139      throw error;140    }141  }142}143