Reimplemented without regex

Author: Markus Suonto

openstack/client.go

@@ -3,7 +3,7 @@ package openstack
 import (
 	"fmt"
 	"net/url"
-	"regexp"
+	"strconv"
 	"strings"
 
 	"github.com/rackspace/gophercloud"
@@ -17,8 +17,6 @@ const (
 	v30 = "v3.0"
 )
 
-var VERSION_PATTERN = regexp.MustCompile("/v[1-9]{1}[0-9\\.]{0,2}/")
-
 // NewClient prepares an unauthenticated ProviderClient instance.
 // Most users will probably prefer using the AuthenticatedClient function instead.
 // This is useful if you wish to explicitly control the version of the identity service that's used for authentication explicitly,
@@ -34,23 +32,33 @@ func NewClient(endpoint string) (*gophercloud.ProviderClient, error) {
 	// Base is url with path
 	endpoint = gophercloud.NormalizeURL(endpoint)
 	base := gophercloud.NormalizeURL(u.String())
-	var location = VERSION_PATTERN.FindStringIndex(base)
-
-	if location != nil {
-		var version = base[location[0]+1:location[1]-1]
-		switch version {
-		case "v2.0", "v3":
-			// post version suffixes in path are not supported
-			if len(base) > location[1] {
-				return nil, fmt.Errorf("Path suffixes (after version) are not supported.")
+
+	path := u.Path
+	if !strings.HasSuffix(path, "/") {
+		path = path + "/"
+	}
+
+	parts := strings.Split(path[0:len(path)-1], "/")
+	for index,version := range(parts) {
+		if 2 <= len(version) && len(version) <= 4 && strings.HasPrefix(version, "v") {
+			_, err := strconv.ParseFloat(version[1:], 64)
+			if err == nil {
+				// post version suffixes in path are not supported
+				// version must be on the last index
+				if index < len(parts) - 1 {
+					return nil, fmt.Errorf("Path suffixes (after version) are not supported.")
+				}
+				switch version {
+				case "v2.0", "v3":
+					// valid version found, strip from base
+					return &gophercloud.ProviderClient{
+						IdentityBase:     base[0:len(base)-len(version)-1],
+						IdentityEndpoint: endpoint,
+					}, nil
+				default:
+					return nil, fmt.Errorf("Invalid identity endpoint version %v. Supported versions: v2.0, v3", version)
+				}
 			}
-			// valid version found, strip from base
-			return &gophercloud.ProviderClient{
-				IdentityBase:     base[0:location[0]+1],
-				IdentityEndpoint: endpoint,
-			}, nil
-		default:
-			return nil, fmt.Errorf("Invalid identity endpoint version %v. Supported versions: v2.0, v3", version)
 		}
 	}