gofiber/fiber · error

failed to parse

Error message

failed to parse: %w

What it means

Returned on the fallback branch of DefaultRes.Render() when no Views engine is configured (app.config.Views == nil). Fiber reads the file at path 'name', parses its contents through the standard library html/template, and wraps a parse failure with 'failed to parse'. This is Go's own template grammar, not an external engine.

Solutions

1. Open the file named in the call and run `go tool tmpl` or `gotemplate` against it to get the exact line/column of the syntax error.
2. Fix the template grammar: balance {{if}}/{{end}}, {{range}}/{{end}}, {{define}}/{{end}}, and close every action with }}.
3. If you intended to use a non-Go engine, set Config.Views to the appropriate gofiber/template engine instead of relying on the raw fallback.
4. Remove stray BOM/encoding artifacts from the file.

Example fix

// before — broken Go template
// user.gohtml: {{ .Name }} {{ end }}
return c.Render("user.gohtml", fiber.Map{"Name": "Ada"})
// -> failed to parse: template: :1: unexpected {{end}}

// after — balanced
// user.gohtml: {{ .Name }}
return c.Render("user.gohtml", fiber.Map{"Name": "Ada"})

// Parse templates at build/test time to catch syntax errors early.
import "html/template"
func validateTemplateFile(path string) error {
    b, err := os.ReadFile(path)
    if err != nil { return err }
    _, err = template.New(path).Parse(string(b))
    return err
}

if err := c.Render(file, bind); err != nil {
    if strings.Contains(err.Error(), "failed to parse") {
        log.Printf("template syntax error in %s: %v", file, err)
        return fiber.ErrInternalServerError
    }
    return err
}

When it happens

Trigger: Calling ctx.Render(name, bind) with app.config.Views unset, where 'name' points to a file whose contents violate Go text/template or html/template syntax: unclosed action {{, unmatched define, invalid pipeline, bad delimiter.

Common situations: Using Fiber without a template engine but shipping .gohtml files; migrating from a Handlebars/Pug engine to raw Go templates without rewriting syntax; editor saving with BOM or mixed encoding that breaks the {{ }} delimiters; a typo like {{ end}} without a matching {{ if }}.

Understand the failure class

• Parsing and encoding errors: unexpected token, malformed input — why parsers reject input and how to find the real culprit.

Related errors

• failed to execute
• ErrUnknownTag
• failed to convert
• failed to open
• failed to read

AI-assisted analysis of gofiber/fiber@a105acad6c (2026-08-11). Data as JSON: /api/errors/294e05deff07ff19. Report an issue: GitHub.

Appendix: source

Thrown at res.go:944

					return err
				}

				rendered = true
				break
			}
		}
	}

	if !rendered {
		// Render raw template using 'name' as filepath if no engine is set
		var tmpl *template.Template
		if _, err := readContent(buf, name); err != nil {
			return err
		}
		// Parse template
		tmpl, err := template.New("").Parse(rootApp.toString(buf.Bytes()))
		if err != nil {
			return fmt.Errorf("failed to parse: %w", err)
		}
		buf.Reset()
		// Render template
		if err := tmpl.Execute(buf, bind); err != nil {
			return fmt.Errorf("failed to execute: %w", err)
		}
	}

	response := &r.c.fasthttp.Response

	// Set Content-Type to text/html
	response.Header.SetContentType(MIMETextHTMLCharsetUTF8)
	// Set rendered template to body
	response.SetBody(buf.Bytes())

	return nil
}

View on GitHub (pinned to a105acad6c)