fix: 修复预览与 PDF 渲染边界问题

apps/server/src/app.ts

@@ -8,7 +8,11 @@ import {
   exportConfigSchema,
   supportedPaperFormats
 } from "@md-to-pdf/core";
-import { RENDERER_VERSION, renderMarkdown } from "@md-to-pdf/renderer";
+import {
+  MarkdownDocumentParseError,
+  RENDERER_VERSION,
+  renderMarkdown
+} from "@md-to-pdf/renderer";
 import {
   createPdfGenerator,
   PdfEngineClosedError,
@@ -66,6 +70,29 @@ function validateMarkdownRequest(
   };
 }
 
+function renderMarkdownRequest(
+  markdown: string,
+  language: string | undefined
+) {
+  try {
+    return {
+      success: true as const,
+      document: renderMarkdown(markdown, {
+        ...(language ? { language } : {})
+      })
+    };
+  } catch (error) {
+    if (error instanceof MarkdownDocumentParseError) {
+      return {
+        success: false as const,
+        error: error.code,
+        message: error.message
+      };
+    }
+    throw error;
+  }
+}
+
 function encodeRfc5987(value: string) {
   return encodeURIComponent(value).replace(
     /[!'()*]/g,
@@ -142,7 +169,8 @@ export function buildApp(options: BuildAppOptions = {}) {
   const themes = createThemeRegistry({
     bundledRoot: resolve(projectRoot, "themes"),
     localRoot:
-      options.localThemeRoot ?? resolve(projectRoot, ".local", "themes")
+      options.localThemeRoot ?? resolve(projectRoot, ".local", "themes"),
+    onWarning: (message) => app.log.warn(message)
   });
   const pdfGenerator =
     options.pdfGenerator ?? createPdfGenerator();
@@ -254,9 +282,17 @@ export function buildApp(options: BuildAppOptions = {}) {
         });
       }
 
-      return renderMarkdown(validated.markdown, {
-        ...(validated.language ? { language: validated.language } : {})
-      });
+      const rendered = renderMarkdownRequest(
+        validated.markdown,
+        validated.language
+      );
+      if (!rendered.success) {
+        return reply.code(400).send({
+          error: rendered.error,
+          message: rendered.message
+        });
+      }
+      return rendered.document;
     }
   );
 
@@ -304,10 +340,18 @@ export function buildApp(options: BuildAppOptions = {}) {
       }
 
       const markdownStartedAt = performance.now();
-      const rendered = renderMarkdown(validated.markdown, {
-        ...(validated.language ? { language: validated.language } : {})
-      });
+      const renderedResult = renderMarkdownRequest(
+        validated.markdown,
+        validated.language
+      );
       const markdownMs = performance.now() - markdownStartedAt;
+      if (!renderedResult.success) {
+        return reply.code(400).send({
+          error: renderedResult.error,
+          message: renderedResult.message
+        });
+      }
+      const rendered = renderedResult.document;
 
       try {
         const generated = await pdfGenerator.generate({

apps/server/src/pdf-engine.ts

@@ -232,6 +232,46 @@ export function isAllowedPdfRequestUrl(
   return url.origin === renderOrigin;
 }
 
+async function waitWithPdfTimeout<T>(
+  operation: Promise<T>,
+  timeoutMs: number
+) {
+  let timeout: NodeJS.Timeout | undefined;
+  try {
+    return await Promise.race([
+      operation,
+      new Promise<never>((_, reject) => {
+        timeout = setTimeout(() => {
+          reject(new PdfRenderTimeoutError(timeoutMs));
+        }, timeoutMs);
+      })
+    ]);
+  } finally {
+    if (timeout) {
+      clearTimeout(timeout);
+    }
+  }
+}
+
+async function closeContextWithin(
+  context: Awaited<ReturnType<Browser["newContext"]>>,
+  timeoutMs: number
+) {
+  let timeout: NodeJS.Timeout | undefined;
+  try {
+    await Promise.race([
+      context.close().catch(() => undefined),
+      new Promise<void>((resolve) => {
+        timeout = setTimeout(resolve, Math.min(timeoutMs, 5_000));
+      })
+    ]);
+  } finally {
+    if (timeout) {
+      clearTimeout(timeout);
+    }
+  }
+}
+
 export class PlaywrightPdfGenerator implements PdfGenerator {
   private readonly renderOrigin: string;
   private readonly renderUrl: string;
@@ -284,7 +324,7 @@ export class PlaywrightPdfGenerator implements PdfGenerator {
     if (this.closed) {
       throw new PdfEngineClosedError();
     }
-    await this.getBrowser();
+    await waitWithPdfTimeout(this.getBrowser(), this.timeoutMs);
   }
 
   async close() {
@@ -330,57 +370,67 @@ export class PlaywrightPdfGenerator implements PdfGenerator {
     queuedAt: number,
     queueMs: number
   ): Promise<PdfGenerationResult> {
-    const browserStartedAt = performance.now();
-    const browser = await this.getBrowser();
-    const browserMs = performance.now() - browserStartedAt;
-    const contextStartedAt = performance.now();
-    const context = await browser.newContext({
-      locale: payload.metadata.language || "zh-CN",
-      serviceWorkers: "block"
-    });
-    const contextMs = performance.now() - contextStartedAt;
-    let timeout: NodeJS.Timeout | undefined;
+    let context:
+      | Awaited<ReturnType<Browser["newContext"]>>
+      | undefined;
+    let expired = false;
 
     try {
-      await context.route("**/*", async (route) => {
-        if (
-          isAllowedPdfRequestUrl(
-            route.request().url(),
-            this.renderOrigin
-          )
-        ) {
-          await route.continue();
-          return;
+      const operation = (async (): Promise<PdfGenerationResult> => {
+        const browserStartedAt = performance.now();
+        const browser = await this.getBrowser();
+        const browserMs = performance.now() - browserStartedAt;
+        if (expired) {
+          throw new PdfRenderTimeoutError(this.timeoutMs);
         }
-        await route.abort("blockedbyclient");
-      });
 
-      const operation = this.renderWithContext(context, payload);
-      const timeoutPromise = new Promise<never>((_, reject) => {
-        timeout = setTimeout(() => {
-          reject(new PdfRenderTimeoutError(this.timeoutMs));
-        }, this.timeoutMs);
-      });
-
-      const generated = await Promise.race([
-        operation,
-        timeoutPromise
-      ]);
-      return {
-        ...generated,
-        timings: {
-          queueMs,
-          browserMs,
-          contextMs,
-          ...generated.timings,
-          totalMs: performance.now() - queuedAt
+        const contextStartedAt = performance.now();
+        const createdContext = await browser.newContext({
+          locale: payload.metadata.language || "zh-CN",
+          serviceWorkers: "block"
+        });
+        context = createdContext;
+        const contextMs = performance.now() - contextStartedAt;
+        if (expired) {
+          await closeContextWithin(createdContext, this.timeoutMs);
+          throw new PdfRenderTimeoutError(this.timeoutMs);
         }
-      };
+
+        await createdContext.route("**/*", async (route) => {
+          if (
+            isAllowedPdfRequestUrl(
+              route.request().url(),
+              this.renderOrigin
+            )
+          ) {
+            await route.continue();
+            return;
+          }
+          await route.abort("blockedbyclient");
+        });
+
+        const generated = await this.renderWithContext(
+          createdContext,
+          payload
+        );
+        return {
+          ...generated,
+          timings: {
+            queueMs,
+            browserMs,
+            contextMs,
+            ...generated.timings,
+            totalMs: performance.now() - queuedAt
+          }
+        };
+      })();
+
+      return await waitWithPdfTimeout(operation, this.timeoutMs);
     } finally {
-      if (timeout) {
-        clearTimeout(timeout);
+      expired = true;
+      if (context) {
+        await closeContextWithin(context, this.timeoutMs);
       }
-      await context.close().catch(() => undefined);
     }
   }
 

apps/server/src/theme-registry.ts

@@ -26,6 +26,7 @@ export interface ThemeRecord {
 export interface ThemeRegistryOptions {
   bundledRoot: string;
   localRoot: string;
+  onWarning?: (message: string) => void;
 }
 
 const assetContentTypes: Record<string, string> = {
@@ -92,7 +93,8 @@ async function resolveThemeFile(directory: string, relativePath: string) {
 
 async function readThemeRoot(
   root: string,
-  source: ThemeRecord["source"]
+  source: ThemeRecord["source"],
+  onWarning?: (message: string) => void
 ): Promise<ThemeRecord[]> {
   let entries;
   try {
@@ -139,6 +141,10 @@ async function readThemeRoot(
       });
     } catch (error) {
       const message = error instanceof Error ? error.message : String(error);
+      if (source === "local") {
+        onWarning?.(`已忽略无效本地主题 ${entry.name}：${message}`);
+        continue;
+      }
       throw new Error(`主题 ${entry.name} 无效：${message}`);
     }
   }
@@ -272,7 +278,7 @@ export function createThemeRegistry(options: ThemeRegistryOptions) {
   async function list() {
     const [bundledThemes, localThemes] = await Promise.all([
       readThemeRoot(options.bundledRoot, "bundled"),
-      readThemeRoot(options.localRoot, "local")
+      readThemeRoot(options.localRoot, "local", options.onWarning)
     ]);
 
     const themes = [...bundledThemes, ...localThemes];