Move the extensions resource to common/.
diff --git a/openstack/common/extensions/results.go b/openstack/common/extensions/results.go
new file mode 100644
index 0000000..2b8d8b7
--- /dev/null
+++ b/openstack/common/extensions/results.go
@@ -0,0 +1,73 @@
+package extensions
+
+import (
+ "fmt"
+
+ "github.com/mitchellh/mapstructure"
+ "github.com/rackspace/gophercloud"
+ "github.com/rackspace/gophercloud/pagination"
+)
+
+// GetResult temporarility stores the result of a Get call.
+// Use its Extract() method to interpret it as an Extension.
+type GetResult struct {
+ gophercloud.CommonResult
+}
+
+// Extract interprets a GetResult as an Extension.
+func (r GetResult) Extract() (*Extension, error) {
+ if r.Err != nil {
+ return nil, r.Err
+ }
+
+ var res struct {
+ Extension *Extension `json:"extension"`
+ }
+
+ err := mapstructure.Decode(r.Resp, &res)
+ if err != nil {
+ return nil, fmt.Errorf("Error decoding OpenStack extension: %v", err)
+ }
+
+ return res.Extension, nil
+}
+
+// Extension is a struct that represents an OpenStack extension.
+type Extension struct {
+ Updated string `json:"updated"`
+ Name string `json:"name"`
+ Links []interface{} `json:"links"`
+ Namespace string `json:"namespace"`
+ Alias string `json:"alias"`
+ Description string `json:"description"`
+}
+
+// ExtensionPage is the page returned by a pager when traversing over a collection of extensions.
+type ExtensionPage struct {
+ pagination.SinglePageBase
+}
+
+// IsEmpty checks whether an ExtensionPage struct is empty.
+func (r ExtensionPage) IsEmpty() (bool, error) {
+ is, err := ExtractExtensions(r)
+ if err != nil {
+ return true, err
+ }
+ return len(is) == 0, nil
+}
+
+// ExtractExtensions accepts a Page struct, specifically an ExtensionPage struct, and extracts the
+// elements into a slice of Extension structs.
+// In other words, a generic collection is mapped into a relevant slice.
+func ExtractExtensions(page pagination.Page) ([]Extension, error) {
+ var resp struct {
+ Extensions []Extension `mapstructure:"extensions"`
+ }
+
+ err := mapstructure.Decode(page.(ExtensionPage).Body, &resp)
+ if err != nil {
+ return nil, err
+ }
+
+ return resp.Extensions, nil
+}