add progress to function

converter/converter.go

@@ -18,9 +18,10 @@ import (
 // html to pdf converter structure for
 type Converter struct {
 	chromePath    string
-	ctx         context.Context
-	cancel      context.CancelFunc
-	allocCancel context.CancelFunc
+	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)
 }
 
@@ -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 +112,84 @@ 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
+}
+
+// Convert converts all given input files
+func (c *Converter) ConvertHtmls(htmls ...models.Html) error {
+	for i, h := range htmls {
+		if c.progress != nil {
+			c.progress(i + 1)
+		}
+		if len(h.Html) == 0 {
+			return fmt.Errorf("no .html input provided")
+		} else if h.Output == "" || filepath.Ext(h.Output) != ".pdf" {
+			return fmt.Errorf("no .pdf output file path provided: %s", h.Output)
+		}
+
+		taskCtx, taskCancel := chromedp.NewContext(c.browserCtx)
+		timeoutCtx, timeoutCancel := context.WithTimeout(taskCtx, 60*time.Second)
+
+		var pdfData []byte
+		err := chromedp.Run(timeoutCtx,
+			// Start with a blank page
+			chromedp.Navigate("about:blank"),
+			// Inject HTML directly
+			chromedp.ActionFunc(func(ctx context.Context) error {
+				frameTree, err := page.GetFrameTree().Do(ctx)
+				if err != nil {
+					return err
+				}
+
+				return page.SetDocumentContent(frameTree.Frame.ID, string(h.Html)).Do(ctx)
+			}),
+			chromedp.WaitReady("body", chromedp.ByQuery),
+			chromedp.ActionFunc(func(ctx context.Context) error {
+				buf, _, err := page.PrintToPDF().
+					WithPrintBackground(true).
+					WithPaperWidth(8.27).
+					WithPaperHeight(11.69).
+					Do(ctx)
+				if err != nil {
+					return err
+				}
+				pdfData = buf
+				return nil
+			}),
+		)
+
+		timeoutCancel()
+		taskCancel()
+		if err != nil {
+			return err
+		}
+
+		// Save PDF to file
+		if err := os.WriteFile(h.Output, pdfData, 0644); err != nil {
+			return err
+		}
+	}
 	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()
 	}
 }
 

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 (
+	"bytes"
 	"fmt"
 	"os"
 	"path/filepath"
@@ -46,6 +47,7 @@ func TestConvertFiles(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
+	defer c.Close()
 
 	c.SetProgressCallback(func(progress int) {
 		fmt.Println(progress)
@@ -56,3 +58,62 @@ func TestConvertFiles(t *testing.T) {
 	}
 	t.Log("test successfull")
 }
+
+func TestConvertHtml(t *testing.T) {
+	t.Log("start test ConvertHtml")
+
+	// Skip in short mode (useful for CI)
+	if testing.Short() {
+		t.Skip("skipping ConvertHtml integration test in short mode")
+	}
+
+	html := []byte(`
+<!DOCTYPE html>
+<html>
+<head>
+	<meta charset="utf-8">
+	<title>Test PDF</title>
+	<style>
+		body { font-family: Arial, sans-serif; }
+		h1 { color: #333; }
+	</style>
+</head>
+<body>
+	<h1>Hello PDF</h1>
+	<p>This is a test.</p>
+</body>
+</html>
+`)
+
+	tmpDir := t.TempDir()
+	outputPath := filepath.Join(tmpDir, "test.pdf")
+
+	c, err := converter.NewConverter("assets/chrome-headless-shell/win64")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer c.Close()
+
+	err = c.ConvertHtmls(models.Html{Html: html, Output: outputPath})
+	if err != nil {
+		t.Fatalf("ConvertHtml failed: %v", err)
+	}
+
+	// Assert PDF exists
+	data, err := os.ReadFile(outputPath)
+	if err != nil {
+		t.Fatalf("PDF not created: %v", err)
+	}
+
+	// Assert non-empty
+	if len(data) == 0 {
+		t.Fatal("PDF file is empty")
+	}
+
+	// Assert valid PDF header
+	if !bytes.HasPrefix(data, []byte("%PDF-")) {
+		t.Fatalf("output is not a valid PDF (missing %%PDF- header)")
+	}
+
+	t.Log("ConvertHtml test successful")
+}

models/html.go

@@ -0,0 +1,9 @@
+package models
+
+type Htmls []Html
+
+// input model for converter
+type Html struct {
+	Html   []byte
+	Output string
+}