source: code/trunk/vendor/github.com/lib/pq/url.go@ 822

package pq

import (
        "fmt"
        "net"
        nurl "net/url"
        "sort"
        "strings"
)

// 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
}