Move validation for port into util library (#135)

since this way it can be reused by other implementors.

cmd/sanssh/main.go

@@ -109,28 +109,6 @@ func init() {
 	subcommands.ImportantFlag("v")
 }
 
-func hasPort(s string) bool {
-	// Returns true if the provided address does not include a port number.
-	return strings.LastIndex(s, "]") < strings.LastIndex(s, ":")
-}
-
-func validateAndAddPort(s string, port int) string {
-	// See if there's a duration appended and pull it off
-	p := strings.Split(s, ";")
-	if len(p) == 0 || len(p) > 2 || p[0] == "" {
-		log.Fatalf("Invalid address %q - should be of the form host[:port][;<duration>]", s)
-	}
-	new := s
-	if !hasPort(p[0]) {
-		new = fmt.Sprintf("%s:%d", p[0], port)
-		if len(p) == 2 {
-			// Add duration back if we pulled it off.
-			new = fmt.Sprintf("%s;%s", new, p[1])
-		}
-	}
-	return new
-}
-
 func main() {
 	// If this is blank it'll remain blank which is fine
 	// as that means just talk to --targets[0] instead.
@@ -161,11 +139,11 @@ func main() {
 
 	// Validate and add the default proxy port (if needed).
 	if *proxyAddr != "" {
-		*proxyAddr = validateAndAddPort(*proxyAddr, defaultProxyPort)
+		*proxyAddr = cmdUtil.ValidateAndAddPort(*proxyAddr, defaultProxyPort)
 	}
 	// Validate and add the default target port (if needed) for each target.
 	for i, t := range *targetsFlag.Target {
-		(*targetsFlag.Target)[i] = validateAndAddPort(t, defaultTargetPort)
+		(*targetsFlag.Target)[i] = cmdUtil.ValidateAndAddPort(t, defaultTargetPort)
 	}
 
 	clientPolicy := cmdUtil.ChoosePolicy(logr.Discard(), "", *clientPolicyFlag, *clientPolicyFile)

cmd/util/util.go

@@ -19,7 +19,10 @@ package util
 
 import (
 	"errors"
+	"fmt"
+	"log"
 	"os"
+	"strings"
 
 	"github.com/go-logr/logr"
 )
@@ -51,3 +54,28 @@ func ChoosePolicy(logger logr.Logger, defaultPolicy string, policyFlag string, p
 	}
 	return policy
 }
+
+// hasPort returns true if the provided address does not include a port number.
+func hasPort(s string) bool {
+	return strings.LastIndex(s, "]") < strings.LastIndex(s, ":")
+}
+
+// ValidateAndAddPort will take a given target address and optionally add a default port
+// onto it if a port is missing. This will also take in account optional dial timeout
+// suffix and make sure the returned value has that if it exists.
+func ValidateAndAddPort(s string, port int) string {
+	// See if there's a duration appended and pull it off
+	p := strings.Split(s, ";")
+	if len(p) == 0 || len(p) > 2 || p[0] == "" {
+		log.Fatalf("Invalid address %q - should be of the form host[:port][;<duration>]", s)
+	}
+	new := s
+	if !hasPort(p[0]) {
+		new = fmt.Sprintf("%s:%d", p[0], port)
+		if len(p) == 2 {
+			// Add duration back if we pulled it off.
+			new = fmt.Sprintf("%s;%s", new, p[1])
+		}
+	}
+	return new
+}