cmd/tailscale: make cert give hints on usage failure
Like mentioning which cert domain(s) are valid.
"github.com/peterbourgon/ff/v3/ffcli"
"tailscale.com/atomicfile"
"tailscale.com/client/tailscale"
+ "tailscale.com/ipn"
)
var certCmd = &ffcli.Command{
@@ -61,7 +62,19 @@ func runCert(ctx context.Context, args []string) error {
}
if len(args) != 1 {
- return fmt.Errorf("Usage: tailscale cert [flags] <domain>")
+ var hint bytes.Buffer
+ if st, err := tailscale.Status(ctx); err == nil {
+ if st.BackendState != ipn.Running.String() {
+ fmt.Fprintf(&hint, "\nTailscale is not running.\n")
+ } else if len(st.CertDomains) == 0 {
+ fmt.Fprintf(&hint, "\nHTTPS cert support is not enabled/configurfed for your tailnet.\n")
+ } else if len(st.CertDomains) == 1 {
+ fmt.Fprintf(&hint, "\nFor domain, use %q.\n", st.CertDomains[0])
+ } else {
+ fmt.Fprintf(&hint, "\nValid domain options: %q.\n", st.CertDomains)
+ }
+ }
+ return fmt.Errorf("Usage: tailscale cert [flags] <domain>%s", hint.Bytes())
}
domain := args[0]
