Extracts from values by parsing html page

extract_form_values.go

func extractFormValues(reader io.Reader, names []string) (map[string]string, error) {
	result := make(map[string]string, len(names))
	doc, err := html.Parse(reader)
	if err != nil {
		return nil, err
	}
	var rec func(*html.Node)
	rec = func(n *html.Node) {
		if n.Type == html.ElementNode && n.Data == "input" {
			var name, value string
			for _, v := range n.Attr {
				if v.Key == "value" {
					value = v.Val
				}
				if v.Key == "name" {
					name = v.Val
				}
			}
			num := 0
			for _, nv := range names {
				if name == nv {
					result[name] = value
				}
				_, ok := result[name]
				if ok {
					num++
				}
			}
			if num == len(names) {
				return
			}
		}
		for c := n.FirstChild; c != nil; c = c.NextSibling {
			rec(c)
		}
	}
	rec(doc)
	return result, nil
}