fix orphan instances

converter/converter.go

@@ -18,13 +18,17 @@ import (
 // html to pdf converter structure for
 type Converter struct {
 	chromePath    string
-	ctx        context.Context
+	allocCtx      context.Context
-	cancel     context.CancelFunc
+	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
 func NewConverter(chromePath string) (*Converter, error) {
 	var err error
+
 	c := &Converter{chromePath: chromePath}
 	chromePath, err = c.getChromePath()
 	if err != nil {
@@ -38,15 +42,33 @@ func NewConverter(chromePath string) (*Converter, error) {
 		chromedp.DisableGPU,
 	)
 
-	var allocCtx context.Context
+	opts = append(opts, platformOptions())
-	allocCtx, c.cancel = chromedp.NewExecAllocator(context.Background(), opts...)
+
-	c.ctx, c.cancel = 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
 }
 
+func (c *Converter) SetProgressCallback(cb func(progress int)) {
+	c.progress = cb
+}
+
 // Convert converts all given input files
 func (c *Converter) Convert(files ...models.File) error {
-	for _, f := range files {
+	for i, f := range files {
+		if c.progress != nil {
+			c.progress(i + 1)
+		}
+
 		if f.Input == "" || filepath.Ext(f.Input) != ".html" {
 			return fmt.Errorf("no .html input file path provided: %s", f.Input)
 		} else if f.Output == "" || filepath.Ext(f.Output) != ".pdf" {
@@ -69,11 +91,11 @@ func (c *Converter) Convert(files ...models.File) error {
 
 		htmlURL.WriteString(filepath.ToSlash(absPath))
 
-		c.ctx, c.cancel = context.WithTimeout(c.ctx, 60*time.Second)
+		taskCtx, taskCancel := chromedp.NewContext(c.browserCtx)
-		defer c.cancel()
+		timeoutCtx, timeoutCancel := context.WithTimeout(taskCtx, 60*time.Second)
 
 		var pdfData []byte
-		err = chromedp.Run(c.ctx,
+		err = chromedp.Run(timeoutCtx,
 			chromedp.Navigate(htmlURL.String()),
 			chromedp.WaitReady("body", chromedp.ByQuery),
 			chromedp.ActionFunc(func(ctx context.Context) error {
@@ -89,6 +111,9 @@ func (c *Converter) Convert(files ...models.File) error {
 				return nil
 			}),
 		)
+
+		timeoutCancel()
+		taskCancel()
 		if err != nil {
 			return err
 		}
@@ -101,6 +126,16 @@ func (c *Converter) Convert(files ...models.File) error {
 	return nil
 }
 
+func (c *Converter) Close() {
+	// Close browser first, then allocator
+	if c.browserCancel != nil {
+		c.browserCancel()
+	}
+	if c.allocCancel != nil {
+		c.allocCancel()
+	}
+}
+
 // getChromePath checks for system Chrome, else falls back to bundled headless shell
 func (c *Converter) getChromePath() (string, error) {
 

converter/hideOthers.go

@@ -0,0 +1,10 @@
+//go:build !windows
+
+package converter
+
+import "github.com/chromedp/chromedp"
+
+func platformOptions() chromedp.ExecAllocatorOption {
+	// Returns a no-op option for Mac/Linux
+	return chromedp.NoSandbox
+}

converter/hideWindows.go

@@ -0,0 +1,20 @@
+//go:build windows
+
+package converter
+
+import (
+	"os/exec"
+	"syscall"
+
+	"github.com/chromedp/chromedp"
+)
+
+func platformOptions() chromedp.ExecAllocatorOption {
+	return chromedp.ModifyCmdFunc(func(cmd *exec.Cmd) {
+		if cmd.SysProcAttr == nil {
+			cmd.SysProcAttr = &syscall.SysProcAttr{}
+		}
+		cmd.SysProcAttr.HideWindow = true
+		cmd.SysProcAttr.CreationFlags = 0x08000000 // CREATE_NO_WINDOW
+	})
+}

html2pdf.go

@@ -15,6 +15,8 @@ func Convert(chromePath, inputFile, outputFile string) error {
 	if err != nil {
 		return err
 	}
+	defer c.Close()
+
 	return c.Convert(input)
 }
 

html2pdf_test.go

@@ -1,6 +1,7 @@
 package html2pdf
 
 import (
+	"fmt"
 	"os"
 	"path/filepath"
 	"strings"
@@ -41,10 +42,15 @@ func TestConvertFiles(t *testing.T) {
 		})
 	}
 
-	c, err := converter.NewConverter("./assets")
+	c, err := converter.NewConverter("assets/chrome-headless-shell/win64")
 	if err != nil {
 		t.Fatal(err)
 	}
+	defer c.Close()
+
+	c.SetProgressCallback(func(progress int) {
+		fmt.Println(progress)
+	})
 
 	if err := c.Convert(input...); err != nil {
 		t.Fatal(err)