fix orphan instances

converter/converter.go

@@ -17,11 +17,12 @@ import (
 
 // html to pdf converter structure for
 type Converter struct {
-	chromePath  string
-	ctx         context.Context
-	cancel      context.CancelFunc
-	allocCancel context.CancelFunc
-	progress    func(progress int)
+	chromePath    string
+	allocCtx      context.Context
+	allocCancel   context.CancelFunc // Cancels the whole Chrome process manager
+	browserCtx    context.Context    // The specific browser instance
+	browserCancel context.CancelFunc // Closes the browser
+	progress      func(progress int)
 }
 
 // NewConverter starts a new converter instance with a chrome headless shell executable
@@ -43,9 +44,17 @@ func NewConverter(chromePath string) (*Converter, error) {
 
 	opts = append(opts, platformOptions())
 
-	var allocCtx context.Context
-	allocCtx, c.cancel = chromedp.NewExecAllocator(context.Background(), opts...)
-	c.ctx, c.allocCancel = chromedp.NewContext(allocCtx)
+	c.allocCtx, c.allocCancel = chromedp.NewExecAllocator(context.Background(), opts...)
+	c.browserCtx, c.browserCancel = chromedp.NewContext(c.allocCtx)
+
+	// 5. "Warm up" the browser to ensure the executable actually runs
+	// This catches "file not found" or permission errors immediately
+	err = chromedp.Run(c.browserCtx)
+	if err != nil {
+		c.Close() // Cleanup if start fails
+		return nil, fmt.Errorf("failed to start chrome: %w", err)
+	}
+
 	return c, nil
 }
 
@@ -82,11 +91,11 @@ func (c *Converter) Convert(files ...models.File) error {
 
 		htmlURL.WriteString(filepath.ToSlash(absPath))
 
-		ctx, cancel := context.WithTimeout(c.ctx, 60*time.Second)
-		defer cancel()
+		taskCtx, taskCancel := chromedp.NewContext(c.browserCtx)
+		timeoutCtx, timeoutCancel := context.WithTimeout(taskCtx, 60*time.Second)
 
 		var pdfData []byte
-		err = chromedp.Run(ctx,
+		err = chromedp.Run(timeoutCtx,
 			chromedp.Navigate(htmlURL.String()),
 			chromedp.WaitReady("body", chromedp.ByQuery),
 			chromedp.ActionFunc(func(ctx context.Context) error {
@@ -103,24 +112,27 @@ func (c *Converter) Convert(files ...models.File) error {
 			}),
 		)
 
+		timeoutCancel()
+		taskCancel()
 		if err != nil {
-			c.cancel()
 			return err
 		}
 
 		// Save PDF to file
 		if err := os.WriteFile(f.Output, pdfData, 0644); err != nil {
-			c.cancel()
 			return err
 		}
 	}
-	c.cancel()
 	return nil
 }
 
 func (c *Converter) Close() {
-	if c.cancel != nil {
-		c.cancel()
+	// Close browser first, then allocator
+	if c.browserCancel != nil {
+		c.browserCancel()
+	}
+	if c.allocCancel != nil {
+		c.allocCancel()
 	}
 }