huge refactoring

internal/pkg/printer/markdown.go

@@ -7,37 +7,46 @@ import (
 	"io/ioutil"
 	"path/filepath"
 
-	"github.com/labstack/gommon/random"
 	"github.com/microcosm-cc/bluemonday"
 	"github.com/russross/blackfriday/v2"
-	"github.com/thecodingmachine/gotenberg/internal/pkg/standarderror"
+	"github.com/thecodingmachine/gotenberg/internal/pkg/xerror"
+	"github.com/thecodingmachine/gotenberg/internal/pkg/xlog"
+	"github.com/thecodingmachine/gotenberg/internal/pkg/xrand"
 )
 
-// NewMarkdown returns a Markdown printer.
-func NewMarkdown(fpath string, opts *ChromeOptions) (Printer, error) {
-	const op string = "printer.NewMarkdown"
-	tmpl, err := template.
-		New(filepath.Base(fpath)).
-		Funcs(template.FuncMap{"toHTML": markdownToHTML}).
-		ParseFiles(fpath)
+// NewMarkdownPrinter returns a Printer which
+// is able to convert Markdown files to PDF.
+func NewMarkdownPrinter(logger xlog.Logger, fpath string, opts ChromePrinterOptions) (Printer, error) {
+	const op string = "printer.NewMarkdownPrinter"
+	resolver := func() (string, error) {
+		tmpl, err := template.
+			New(filepath.Base(fpath)).
+			Funcs(template.FuncMap{"toHTML": markdownToHTML}).
+			ParseFiles(fpath)
+		if err != nil {
+			return "", err
+		}
+		dirPath := filepath.Dir(fpath)
+		data := &templateData{DirPath: dirPath}
+		var buffer bytes.Buffer
+		if err := tmpl.Execute(&buffer, data); err != nil {
+			return "", err
+		}
+		baseFilename := xrand.Get()
+		dst := fmt.Sprintf("%s/%s.html", dirPath, baseFilename)
+		if err := ioutil.WriteFile(dst, buffer.Bytes(), 0644); err != nil {
+			return "", err
+		}
+		return fmt.Sprintf("file://%s", dst), nil
+	}
+	URL, err := resolver()
 	if err != nil {
-		return nil, &standarderror.Error{Op: op, Err: err}
+		return chromePrinter{}, xerror.New(op, err)
 	}
-	dirPath := filepath.Dir(fpath)
-	data := &templateData{DirPath: dirPath}
-	var buffer bytes.Buffer
-	if err := tmpl.Execute(&buffer, data); err != nil {
-		return nil, &standarderror.Error{Op: op, Err: err}
-	}
-	baseFilename := random.String(32)
-	dst := fmt.Sprintf("%s/%s.html", dirPath, baseFilename)
-	if err := ioutil.WriteFile(dst, buffer.Bytes(), 0644); err != nil {
-		return nil, &standarderror.Error{Op: op, Err: err}
-	}
-	URL := fmt.Sprintf("file://%s", dst)
-	return &chrome{
-		url:  URL,
-		opts: opts,
+	return chromePrinter{
+		logger: logger,
+		url:    URL,
+		opts:   opts,
 	}, nil
 }
 
@@ -50,7 +59,7 @@ func markdownToHTML(dirPath, filename string) (template.HTML, error) {
 	fpath := fmt.Sprintf("%s/%s", dirPath, filename)
 	b, err := ioutil.ReadFile(fpath)
 	if err != nil {
-		return "", &standarderror.Error{Op: op, Err: err}
+		return "", xerror.New(op, err)
 	}
 	unsafe := blackfriday.Run(b)
 	content := bluemonday.UGCPolicy().SanitizeBytes(unsafe)