ai-agent-book 精选快照（<2MB 代码与文档，来自 github.com/bojieli/ai-agent-book）

chapter6/live-audio/backend/utils/providers/asrProviders.js

@@ -0,0 +1,276 @@
+const axios = require('axios');
+const FormData = require('form-data');
+const fs = require('fs');
+const path = require('path');
+
+/**
+ * Base ASR Provider class
+ */
+class BaseASRProvider {
+  constructor(config, apiKey) {
+    this.config = config;
+    this.apiKey = apiKey;
+  }
+
+  /**
+   * Convert raw audio buffer to WAV format
+   * @param {Buffer} audioBuffer - Raw PCM audio data
+   * @param {Object} options - Audio format options
+   * @returns {Buffer} WAV formatted audio data
+   */
+  createWavBuffer(audioBuffer, options = {}) {
+    const sampleRate = options.sampleRate || 16000;
+    const channels = options.channels || 1;
+    const bitsPerSample = options.bitsPerSample || 16;
+    
+    const byteRate = sampleRate * channels * bitsPerSample / 8;
+    const blockAlign = channels * bitsPerSample / 8;
+    const dataSize = audioBuffer.length;
+    const fileSize = 36 + dataSize;
+    
+    const header = Buffer.alloc(44);
+    
+    // RIFF header
+    header.write('RIFF', 0);
+    header.writeUInt32LE(fileSize, 4);
+    header.write('WAVE', 8);
+    
+    // fmt chunk
+    header.write('fmt ', 12);
+    header.writeUInt32LE(16, 16); // PCM format chunk size
+    header.writeUInt16LE(1, 20);  // PCM format
+    header.writeUInt16LE(channels, 22);
+    header.writeUInt32LE(sampleRate, 24);
+    header.writeUInt32LE(byteRate, 28);
+    header.writeUInt16LE(blockAlign, 32);
+    header.writeUInt16LE(bitsPerSample, 34);
+    
+    // data chunk
+    header.write('data', 36);
+    header.writeUInt32LE(dataSize, 40);
+    
+    return Buffer.concat([header, audioBuffer]);
+  }
+
+  async transcribe(audioBuffer, options = {}) {
+    throw new Error('transcribe method must be implemented by subclass');
+  }
+}
+
+/**
+ * OpenAI Whisper ASR Provider
+ */
+class OpenAIASRProvider extends BaseASRProvider {
+  async transcribe(audioBuffer, tempDir, options = {}) {
+    try {
+      // Create WAV buffer
+      const wavBuffer = this.createWavBuffer(audioBuffer, {
+        sampleRate: 16000,
+        channels: 1,
+        bitsPerSample: 16
+      });
+
+      // Create temporary file
+      const tempFileName = `audio_${Date.now()}_${Math.random().toString(36).substring(2)}.wav`;
+      const tempFilePath = path.join(tempDir, tempFileName);
+      
+      // Write audio to temporary file
+      fs.writeFileSync(tempFilePath, wavBuffer);
+
+      try {
+        // Create form data
+        const formData = new FormData();
+        formData.append('file', fs.createReadStream(tempFilePath));
+        formData.append('model', this.config.model);
+        formData.append('response_format', 'json');
+        
+        if (options.language) {
+          formData.append('language', options.language);
+        }
+        
+        if (options.prompt) {
+          formData.append('prompt', options.prompt);
+        }
+
+        // Make API request
+        const response = await axios({
+          method: 'post',
+          url: this.config.apiUrl,
+          data: formData,
+          headers: {
+            'Authorization': `Bearer ${this.apiKey}`,
+            ...formData.getHeaders()
+          },
+          timeout: 30000 // 30 second timeout
+        });
+
+        const result = {
+          success: true,
+          text: response.data.text || '',
+          language: response.data.language || 'unknown',
+          duration: response.data.duration || 0,
+          confidence: response.data.confidence || 1.0,
+          requestId: response.headers?.['x-request-id'] || response.headers?.['request-id'] || null,
+          responseModel: response.data.model || this.config.model,
+          timestamp: Date.now(),
+          provider: 'openai'
+        };
+
+        console.log('OpenAI ASR Result:', {
+          text: result.text,
+          language: result.language,
+          duration: result.duration
+        });
+
+        return result;
+
+      } finally {
+        // Clean up temporary file
+        try {
+          fs.unlinkSync(tempFilePath);
+        } catch (cleanupError) {
+          console.warn('Failed to cleanup temp file:', cleanupError.message);
+        }
+      }
+
+    } catch (error) {
+      console.error('OpenAI ASR error:', error.response?.data || error.message);
+      
+      return {
+        success: false,
+        text: '',
+        error: error.response?.data?.error?.message || error.message,
+        timestamp: Date.now(),
+        provider: 'openai'
+      };
+    }
+  }
+}
+
+/**
+ * SenseVoice via Siliconflow ASR Provider
+ */
+class SiliconflowASRProvider extends BaseASRProvider {
+  async transcribe(audioBuffer, tempDir, options = {}) {
+    try {
+      // Create WAV buffer
+      const wavBuffer = this.createWavBuffer(audioBuffer, {
+        sampleRate: 16000,
+        channels: 1,
+        bitsPerSample: 16
+      });
+
+      // Create temporary file
+      const tempFileName = `audio_${Date.now()}_${Math.random().toString(36).substring(2)}.wav`;
+      const tempFilePath = path.join(tempDir, tempFileName);
+      
+      // Write audio to temporary file
+      fs.writeFileSync(tempFilePath, wavBuffer);
+
+      try {
+        // Create form data
+        const formData = new FormData();
+        formData.append('file', fs.createReadStream(tempFilePath));
+        formData.append('model', this.config.model);
+        formData.append('response_format', 'json');
+        
+        // SenseVoice specific parameters
+        if (options.language) {
+          formData.append('language', options.language);
+        } else {
+          // SenseVoice supports auto language detection
+          formData.append('language', 'auto');
+        }
+        
+        if (options.prompt) {
+          formData.append('prompt', options.prompt);
+        }
+
+        // Make API request
+        const response = await axios({
+          method: 'post',
+          url: this.config.apiUrl,
+          data: formData,
+          headers: {
+            'Authorization': `Bearer ${this.apiKey}`,
+            ...formData.getHeaders()
+          },
+          timeout: 30000 // 30 second timeout
+        });
+
+        const result = {
+          success: true,
+          text: response.data.text || '',
+          language: response.data.language || 'unknown',
+          duration: response.data.duration || 0,
+          confidence: response.data.confidence || 1.0,
+          requestId: response.headers?.['x-request-id'] || response.headers?.['request-id'] || null,
+          responseModel: response.data.model || this.config.model,
+          timestamp: Date.now(),
+          provider: 'siliconflow'
+        };
+
+        console.log('SenseVoice ASR Result:', {
+          text: result.text,
+          language: result.language,
+          duration: result.duration
+        });
+
+        return result;
+
+      } finally {
+        // Clean up temporary file
+        try {
+          fs.unlinkSync(tempFilePath);
+        } catch (cleanupError) {
+          console.warn('Failed to cleanup temp file:', cleanupError.message);
+        }
+      }
+
+    } catch (error) {
+      console.error('SenseVoice ASR error:', error.response?.data || error.message);
+      
+      return {
+        success: false,
+        text: '',
+        error: error.response?.data?.error?.message || error.message,
+        timestamp: Date.now(),
+        provider: 'siliconflow'
+      };
+    }
+  }
+}
+
+/**
+ * ASR Provider Factory
+ */
+class ASRProviderFactory {
+  static createProvider(providerName, config, globalConfig) {
+    const providerConfig = config.ASR_PROVIDERS[providerName];
+    if (!providerConfig) {
+      throw new Error(`ASR provider ${providerName} not found in configuration`);
+    }
+
+    // Get API key from global config
+    const apiKey = globalConfig[providerConfig.apiKey];
+    if (!apiKey) {
+      throw new Error(`API key ${providerConfig.apiKey} not found in configuration`);
+    }
+
+    switch (providerName) {
+      case 'openai':
+        return new OpenAIASRProvider(providerConfig, apiKey);
+      case 'siliconflow':
+        return new SiliconflowASRProvider(providerConfig, apiKey);
+      default:
+        throw new Error(`Unsupported ASR provider: ${providerName}`);
+    }
+  }
+}
+
+module.exports = {
+  BaseASRProvider,
+  OpenAIASRProvider,
+  SiliconflowASRProvider,
+  ASRProviderFactory
+};