Method JSONP

res.go:560–585

JSONP sends a JSON response with JSONP support. This method is identical to JSON, except that it opts-in to JSONP callback support. By default, the callback name is simply callback.

(data any, callback ...string)

// This method is identical to JSON, except that it opts-in to JSONP callback support.
// By default, the callback name is simply callback.
func (r *DefaultRes) JSONP(data any, callback ...string) error {
	raw, err := r.c.app.config.JSONEncoder(data)
	if err != nil {
		return err
	}

	cb := "callback"
	if len(callback) > 0 {
		cb = callback[0]
	}

	// Build JSONP response: callback(data);
	// Use bytebufferpool to avoid string concatenation allocations
	buf := bytebufferpool.Get()
	buf.WriteString(cb)
	buf.WriteByte('(')
	buf.Write(raw)
	buf.WriteString(");")

	r.setCanonical(HeaderXContentTypeOptions, "nosniff")
	r.c.fasthttp.Response.Header.SetContentType(MIMETextJavaScriptCharsetUTF8)
	// Use SetBody (not SetBodyRaw) to copy the bytes before returning buffer to pool
	r.c.fasthttp.Response.SetBody(buf.Bytes())
	bytebufferpool.Put(buf)
	return nil
}

// XML converts any interface or string to XML.
// This method also sets the content header to application/xml; charset=utf-8.