| // Package webbrowser provides a simple API for opening web pages on your |
| // default browser. |
| package webbrowser |
| |
| import ( |
| "errors" |
| "fmt" |
| "net/url" |
| "os" |
| "os/exec" |
| "runtime" |
| "strings" |
| ) |
| |
| var ( |
| ErrCantOpenBrowser = errors.New("webbrowser: can't open browser") |
| ErrNoCandidates = errors.New("webbrowser: no browser candidate found for your OS") |
| ) |
| |
| // Candidates contains a list of registered `Browser`s that will be tried with Open. |
| var Candidates []Browser |
| |
| type Browser interface { |
| // Command returns a ready to be used Cmd that will open an URL. |
| Command(string) (*exec.Cmd, error) |
| // Open tries to open a URL in your default browser. NOTE: This may cause |
| // your program to hang until the browser process is closed in some OSes, |
| // see https://github.com/toqueteos/webbrowser/issues/4. |
| Open(string) error |
| } |
| |
| // Open tries to open a URL in your default browser ensuring you have a display |
| // set up and not running this from SSH. NOTE: This may cause your program to |
| // hang until the browser process is closed in some OSes, see |
| // https://github.com/toqueteos/webbrowser/issues/4. |
| func Open(s string) (err error) { |
| if len(Candidates) == 0 { |
| return ErrNoCandidates |
| } |
| |
| // Try to determine if there's a display available (only linux) and we |
| // aren't on a terminal (all but windows). |
| switch runtime.GOOS { |
| case "linux": |
| // No display, no need to open a browser. Lynx users **MAY** have |
| // something to say about this. |
| if os.Getenv("DISPLAY") == "" { |
| return fmt.Errorf("webbrowser: tried to open %q, no screen found", s) |
| } |
| fallthrough |
| case "darwin": |
| // Check SSH env vars. |
| if os.Getenv("SSH_CLIENT") != "" || os.Getenv("SSH_TTY") != "" { |
| return fmt.Errorf("webbrowser: tried to open %q, but you are running a shell session", s) |
| } |
| } |
| |
| // Try all candidates |
| for _, candidate := range Candidates { |
| err := candidate.Open(s) |
| if err == nil { |
| return nil |
| } |
| } |
| |
| return ErrCantOpenBrowser |
| } |
| |
| func init() { |
| // Register the default Browser for current OS, if it exists. |
| if os, ok := osCommand[runtime.GOOS]; ok { |
| Candidates = append(Candidates, browserCommand{os.cmd, os.args}) |
| } |
| } |
| |
| var ( |
| osCommand = map[string]*browserCommand{ |
| "android": &browserCommand{"xdg-open", nil}, |
| "darwin": &browserCommand{"open", nil}, |
| "freebsd": &browserCommand{"xdg-open", nil}, |
| "linux": &browserCommand{"xdg-open", nil}, |
| "netbsd": &browserCommand{"xdg-open", nil}, |
| "openbsd": &browserCommand{"xdg-open", nil}, // It may be open instead |
| "windows": &browserCommand{"cmd", []string{"/c", "start"}}, |
| } |
| winSchemes = [3]string{"https", "http", "file"} |
| ) |
| |
| type browserCommand struct { |
| cmd string |
| args []string |
| } |
| |
| func (b browserCommand) Command(s string) (*exec.Cmd, error) { |
| u, err := url.Parse(s) |
| if err != nil { |
| return nil, err |
| } |
| |
| validUrl := ensureValidURL(u) |
| |
| b.args = append(b.args, validUrl) |
| |
| return exec.Command(b.cmd, b.args...), nil |
| } |
| |
| func (b browserCommand) Open(s string) error { |
| cmd, err := b.Command(s) |
| if err != nil { |
| return err |
| } |
| |
| return cmd.Run() |
| } |
| |
| func ensureScheme(u *url.URL) { |
| for _, s := range winSchemes { |
| if u.Scheme == s { |
| return |
| } |
| } |
| u.Scheme = "http" |
| } |
| |
| func ensureValidURL(u *url.URL) string { |
| // Enforce a scheme (windows requires scheme to be set to work properly). |
| ensureScheme(u) |
| s := u.String() |
| |
| // Escape characters not allowed by cmd/bash |
| switch runtime.GOOS { |
| case "windows": |
| s = strings.Replace(s, "&", `^&`, -1) |
| } |
| |
| return s |
| } |