Source: url.go in package github.com/lib/pq

ParseURL no longer needs to be used by clients of this library since supplying a URL as a connection string to sql.Open() is now supported: sql.Open("postgres", "postgres://bob:secret@1.2.3.4:5432/mydb?sslmode=verify-full") It remains exported here for backwards-compatibility. ParseURL converts a url to a connection string for driver.Open. Example: "postgres://bob:secret@1.2.3.4:5432/mydb?sslmode=verify-full" converts to: "user=bob password=secret host=1.2.3.4 port=5432 dbname=mydb sslmode=verify-full" A minimal example: "postgres://" This will be blank, causing driver.Open to use all of the defaults

func ParseURL(url string) (string, error) {
	u, err := nurl.Parse(url)
	if err != nil {
		return "", err
	}

	if u.Scheme != "postgres" && u.Scheme != "postgresql" {
		return "", fmt.Errorf("invalid connection protocol: %s", u.Scheme)
	}

	var kvs []string
	escaper := strings.NewReplacer(` `, `\ `, `'`, `\'`, `\`, `\\`)
	accrue := func(k, v string) {
		if v != "" {
			kvs = append(kvs, k+"="+escaper.Replace(v))
		}
	}

	if u.User != nil {
		v := u.User.Username()
		accrue("user", v)

		v, _ = u.User.Password()
		accrue("password", v)
	}

	if host, port, err := net.SplitHostPort(u.Host); err != nil {
		accrue("host", u.Host)
	} else {
		accrue("host", host)
		accrue("port", port)
	}

	if u.Path != "" {
		accrue("dbname", u.Path[1:])
	}

	q := u.Query()
	for k := range q {
		accrue(k, q.Get(k))
	}

	sort.Strings(kvs) // Makes testing easier (not a performance concern)
	return strings.Join(kvs, " "), nil