feat: 实现多 OCR 提供商架构和完整设置页面

## 主要变更 ### OCR 架构 - 新增多提供商 OCR 系统 (Tesseract.js, Baidu OCR, RapidOCR) - 添加 Provider 基类接口和工厂模式 - 支持 provider 自动选择和降级处理 - 新增 RapidOCR Python HTTP 服务 (端口 8080) ### 路径修复 - 修复 Windows 平台路径解析问题 - 统一路径处理工具 (lib/path.ts) - 修复 uploads 目录定位问题 ### 设置页面重构 - 三个标签页：API 配置、OCR 配置、AI 配置 - API 服务器地址配置 - OCR 服务商配置（Tesseract.js, RapidOCR, 百度 OCR） - AI 服务商配置（智谱 GLM, MiniMax, DeepSeek, Kimi, OpenAI, Anthropic） ### 端口配置 - 前端端口: 13056 - 后端端口: 13057 Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-02-26 14:00:22 +08:00
parent 813df6c738
commit f8472987f0
23 changed files with 2321 additions and 275 deletions
@@ -0,0 +1,187 @@
+/**
+ * Baidu OCR Provider
+ * 特点：准确率高、速度快、国内访问快
+ * 缺点：需要付费 (有免费额度)、需要网络连接
+ * 官方文档: https://cloud.baidu.com/doc/OCR/index.html
+ */
+
+import { BaseOCRProvider, IImageSource, OCRRecognitionResult, OCRProviderConfig } from './base.provider';
+import fs from 'fs';
+
+interface BaiduOCRResponse {
+  words_result: Array<{
+    words: string;
+    probability?: {
+      average: number;
+      variance: number;
+      min: number;
+    };
+  }>;
+  error_code?: number;
+  error_msg?: string;
+}
+
+interface BaiduTokenResponse {
+  access_token: string;
+  expires_in: number;
+}
+
+export class BaiduProvider extends BaseOCRProvider {
+  private apiKey: string;
+  private secretKey: string;
+  private accessToken: string | null = null;
+  private tokenExpireTime: number = 0;
+  private apiUrl = 'https://aip.baidubce.com/rest/2.0/ocr/v1/general_basic';
+
+  constructor(config: OCRProviderConfig & { apiKey?: string; secretKey?: string } = {}) {
+    super(config);
+    this.apiKey = config.apiKey || process.env.BAIDU_OCR_API_KEY || '';
+    this.secretKey = config.secretKey || process.env.BAIDU_OCR_SECRET_KEY || '';
+  }
+
+  getName(): string {
+    return 'Baidu OCR';
+  }
+
+  getType(): 'local' | 'cloud' {
+    return 'cloud';
+  }
+
+  /**
+   * 检查配置是否完整
+   */
+  async isAvailable(): Promise<boolean> {
+    return !!(this.apiKey && this.secretKey);
+  }
+
+  /**
+   * 获取访问令牌
+   */
+  private async getAccessToken(): Promise<string> {
+    // 检查缓存
+    if (this.accessToken && Date.now() < this.tokenExpireTime) {
+      return this.accessToken;
+    }
+
+    const url = `https://aip.baidubce.com/oauth/2.0/token?grant_type=client_credentials&client_id=${this.apiKey}&client_secret=${this.secretKey}`;
+
+    const response = await fetch(url);
+    const data = (await response.json()) as BaiduTokenResponse;
+
+    if (!data.access_token) {
+      throw new Error('获取百度 OCR access_token 失败');
+    }
+
+    this.accessToken = data.access_token;
+    this.tokenExpireTime = Date.now() + (data.expires_in - 300) * 1000; // 提前 5 分钟过期
+
+    return this.accessToken;
+  }
+
+  /**
+   * 执行 OCR 识别
+   */
+  async recognize(
+    source: IImageSource,
+    options?: OCRProviderConfig
+  ): Promise<OCRRecognitionResult> {
+    const startTime = Date.now();
+
+    // 检查配置
+    const available = await this.isAvailable();
+    if (!available) {
+      throw new Error('百度 OCR 未配置。请设置 BAIDU_OCR_API_KEY 和 BAIDU_OCR_SECRET_KEY 环境变量');
+    }
+
+    // 获取图片 Base64
+    const imageBase64 = await this.getImageBase64(source);
+
+    // 获取访问令牌
+    const token = await this.getAccessToken();
+
+    // 调用 OCR API
+    const response = await this.withTimeout(
+      fetch(`${this.apiUrl}?access_token=${token}`, {
+        method: 'POST',
+        headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
+        body: `image=${encodeURIComponent(imageBase64)}`,
+      }),
+      options?.timeout || this.config.timeout || 10000
+    );
+
+    const data = (await response.json()) as BaiduOCRResponse;
+    const duration = Date.now() - startTime;
+
+    // 检查错误
+    if (data.error_code) {
+      throw new Error(`百度 OCR 错误: ${data.error_msg} (${data.error_code})`);
+    }
+
+    // 提取文本和置信度
+    const words = data.words_result || [];
+    const text = words.map((w) => w.words).join('\n');
+
+    // 计算平均置信度
+    let confidence = 0.9; // 默认置信度
+    if (words.length > 0 && words[0].probability) {
+      const sum = words.reduce((acc, w) => acc + (w.probability?.average || 0), 0);
+      confidence = (sum / words.length) / 100;
+    }
+
+    return {
+      text: text.trim(),
+      confidence,
+      duration,
+      extra: {
+        provider: 'baidu',
+        wordCount: words.length,
+      },
+    };
+  }
+
+  getRecommendations() {
+    return {
+      maxImageSize: 4 * 1024 * 1024, // 4MB 限制
+      supportedFormats: ['jpg', 'jpeg', 'png', 'bmp'],
+      notes: '百度 OCR 标准版 QPS 限制为 2，每日免费额度 1000 次。适合高精度需求场景。',
+    };
+  }
+
+  /**
+   * 获取图片 Base64
+   */
+  private async getImageBase64(source: IImageSource): Promise<string> {
+    if (source.base64) {
+      // 移除 data URL 前缀
+      return source.base64.replace(/^data:image\/\w+;base64,/, '');
+    }
+
+    if (source.buffer) {
+      return source.buffer.toString('base64');
+    }
+
+    if (source.path) {
+      // 使用基类的路径解析方法
+      const fullPath = this.resolveImagePath(source.path);
+      const buffer = fs.readFileSync(fullPath);
+      return buffer.toString('base64');
+    }
+
+    throw new Error('无效的图片来源');
+  }
+
+  /**
+   * 超时包装
+   */
+  private async withTimeout<T>(promise: Promise<T>, timeout: number): Promise<T> {
+    return Promise.race([
+      promise,
+      new Promise<never>((_, reject) =>
+        setTimeout(() => reject(new Error('timeout')), timeout)
+      ),
+    ]);
+  }
+}
+
+// 导出单例实例
+export const baiduProvider = new BaiduProvider();