Upload screenshotService.js

backend/src/services/screenshotService.js

@@ -1,6 +1,4 @@
 import puppeteer from 'puppeteer';
-// 添加Playwright作为备用截图引擎
-import { chromium } from 'playwright';
 
 class ScreenshotService {
   constructor() {
@@ -13,6 +11,27 @@ class ScreenshotService {
     this.isClosing = false;
     this.isHuggingFaceSpace = process.env.SPACE_ID || process.env.HF_SPACE_ID;
     this.preferredEngine = 'puppeteer'; // 优先使用的截图引擎
+    this.isPlaywrightAvailable = false; // 初始为false，运行时检查
+    this.chromium = null; // Playwright chromium实例
+  }
+
+  // 动态检查和加载Playwright
+  async initPlaywright() {
+    if (this.chromium) return this.chromium; // 已经加载过
+    
+    try {
+      console.log('🎭 尝试动态加载Playwright...');
+      const playwrightModule = await import('playwright');
+      this.chromium = playwrightModule.chromium;
+      this.isPlaywrightAvailable = true;
+      console.log('✅ Playwright动态加载成功，可作为截图备用方案');
+      return this.chromium;
+    } catch (error) {
+      console.warn('⚠️ Playwright动态加载失败，将仅使用Puppeteer进行截图:', error.message);
+      this.isPlaywrightAvailable = false;
+      this.chromium = null;
+      return null;
+    }
   }
 
   async initBrowser() {
@@ -142,6 +161,13 @@ class ScreenshotService {
   }
 
   async initPlaywrightBrowser() {
+    // 先尝试加载Playwright
+    const chromium = await this.initPlaywright();
+    if (!chromium) {
+      console.warn('Playwright不可用，跳过初始化');
+      return null;
+    }
+
     if (this.playwrightBrowser) {
       try {
         const context = await this.playwrightBrowser.newContext();
@@ -460,6 +486,12 @@ class ScreenshotService {
   }
 
   async generateScreenshotWithPlaywright(htmlContent, options = {}) {
+    // 先尝试加载Playwright
+    const chromium = await this.initPlaywright();
+    if (!chromium) {
+      throw new Error('Playwright不可用');
+    }
+
     try {
       console.log('🎭 开始Playwright截图生成...');
       
@@ -523,26 +555,44 @@ class ScreenshotService {
         console.log('✅ Puppeteer截图生成成功');
         return screenshot;
       } catch (puppeteerError) {
-        console.warn('⚠️ Puppeteer截图失败，尝试Playwright:', puppeteerError.message);
+        console.warn('⚠️ Puppeteer截图失败:', puppeteerError.message);
         
+        // 动态检查Playwright是否可用
+        if (await this.initPlaywright()) {
+          console.log('🎭 尝试使用Playwright作为备用方案...');
+          try {
+            const screenshot = await this.generateScreenshotWithPlaywright(htmlContent, options);
+            console.log('✅ Playwright截图生成成功');
+            this.preferredEngine = 'playwright';
+            return screenshot;
+          } catch (playwrightError) {
+            console.warn('⚠️ Playwright截图也失败，使用fallback方法:', playwrightError.message);
+          }
+        } else {
+          console.warn('⚠️ Playwright不可用，直接使用fallback方法');
+        }
+      }
+    } else {
+      // 如果偏好Playwright，先动态检查是否可用
+      if (await this.initPlaywright()) {
         try {
+          console.log('🎭 尝试使用Playwright生成截图');
           const screenshot = await this.generateScreenshotWithPlaywright(htmlContent, options);
           console.log('✅ Playwright截图生成成功');
-          this.preferredEngine = 'playwright';
           return screenshot;
         } catch (playwrightError) {
-          console.warn('⚠️ Playwright截图也失败，使用fallback方法:', playwrightError.message);
+          console.warn('⚠️ Playwright截图失败，尝试Puppeteer:', playwrightError.message);
+          
+          try {
+            const screenshot = await this.generateScreenshotWithPuppeteer(htmlContent, options);
+            console.log('✅ Puppeteer截图生成成功');
+            return screenshot;
+          } catch (puppeteerError) {
+            console.warn('⚠️ Puppeteer截图也失败，使用fallback方法:', puppeteerError.message);
+          }
         }
-      }
-    } else {
-      try {
-        console.log('🎭 尝试使用Playwright生成截图');
-        const screenshot = await this.generateScreenshotWithPlaywright(htmlContent, options);
-        console.log('✅ Playwright截图生成成功');
-        return screenshot;
-      } catch (playwrightError) {
-        console.warn('⚠️ Playwright截图失败，尝试Puppeteer:', playwrightError.message);
-        
+      } else {
+        console.warn('⚠️ Playwright不可用，直接使用Puppeteer');
         try {
           const screenshot = await this.generateScreenshotWithPuppeteer(htmlContent, options);
           console.log('✅ Puppeteer截图生成成功');
@@ -553,6 +603,7 @@ class ScreenshotService {
       }
     }
     
+    // 如果所有截图引擎都���败，生成fallback图片
     const dimensions = this.extractPPTDimensions(htmlContent);
     const fallbackImage = this.generateFallbackImage(
       dimensions.width, 
@@ -564,8 +615,17 @@ class ScreenshotService {
     return fallbackImage;
   }
 
-  setPreferredEngine(engine) {
+  async setPreferredEngine(engine) {
     if (['puppeteer', 'playwright'].includes(engine)) {
+      // 检查所选引擎是否可用
+      if (engine === 'playwright') {
+        const chromium = await this.initPlaywright();
+        if (!chromium) {
+          console.warn('Playwright不可用，保持使用Puppeteer');
+          return;
+        }
+      }
+      
       this.preferredEngine = engine;
       console.log(`截图引擎偏好设置为: ${engine}`);
     }