embedding.ts•3.1 kB
import OpenAI from 'openai';
import { logger } from '../utils/logger.js';
export interface EmbeddingConfig {
apiKey: string;
baseURL?: string;
model: string;
timeout?: number;
maxRetries?: number;
}
export class EmbeddingClient {
private client: OpenAI;
private config: Required<EmbeddingConfig>;
constructor(config: EmbeddingConfig) {
this.config = {
timeout: 60000,
maxRetries: 3,
baseURL: 'https://api.openai.com/v1',
...config,
};
this.client = new OpenAI({
apiKey: this.config.apiKey,
baseURL: this.config.baseURL,
timeout: this.config.timeout,
maxRetries: this.config.maxRetries,
});
}
/**
* 编码文本为向量
*/
async encode(texts: string[]): Promise<number[][]> {
if (texts.length === 0) {
return [];
}
// 过滤和清理输入文本
const validTexts = texts.filter(t => t && t.trim().length > 0);
if (validTexts.length === 0) {
logger.warn('All input texts are empty, skipping embedding');
return texts.map(() => []);
}
// 如果有被过滤的文本，记录警告
if (validTexts.length < texts.length) {
logger.warn(`Filtered out ${texts.length - validTexts.length} empty texts from embedding input`);
}
try {
const response = await this.client.embeddings.create({
model: this.config.model,
input: validTexts,
});
// 如果有被过滤的文本，需要在返回结果中补充空数组
const embeddings = response.data.map(item => item.embedding);
// 重新映射结果，为空文本返回空数组
let embeddingIndex = 0;
return texts.map(text => {
if (!text || text.trim().length === 0) {
return [];
}
return embeddings[embeddingIndex++];
});
} catch (error: any) {
logger.error('Embedding encoding failed', {
error,
errorMessage: error?.message,
errorResponse: error?.response?.data,
errorCode: error?.code,
errorStatus: error?.status,
model: this.config.model,
baseURL: this.config.baseURL,
textsCount: texts.length,
validTextsCount: validTexts.length,
textsPreview: validTexts.slice(0, 2).map(t => t.substring(0, 100))
});
throw error;
}
}
/**
* 编码单个文本为向量
*/
async encodeOne(text: string): Promise<number[]> {
const result = await this.encode([text]);
return result[0] || [];
}
/**
* 计算余弦相似度
*/
cosineSimilarity(vecA: number[], vecB: number[]): number {
if (vecA.length !== vecB.length) {
throw new Error('Vectors must have the same length');
}
let dotProduct = 0;
let normA = 0;
let normB = 0;
for (let i = 0; i < vecA.length; i++) {
dotProduct += vecA[i] * vecB[i];
normA += vecA[i] * vecA[i];
normB += vecB[i] * vecB[i];
}
const denominator = Math.sqrt(normA) * Math.sqrt(normB);
if (denominator === 0) {
return 0;
}
return dotProduct / denominator;
}
}