-// GetThisSystemNode returns a SystemNode for the node we're running
-// on right now.
-func (cc *Cluster) GetThisSystemNode() (*SystemNode, error) {
- hostname, err := os.Hostname()
+type InstanceTypeMap map[string]InstanceType
+
+var errDuplicateInstanceTypeName = errors.New("duplicate instance type name")
+
+// UnmarshalJSON handles old config files that provide an array of
+// instance types instead of a hash.
+func (it *InstanceTypeMap) UnmarshalJSON(data []byte) error {
+ if len(data) > 0 && data[0] == '[' {
+ var arr []InstanceType
+ err := json.Unmarshal(data, &arr)
+ if err != nil {
+ return err
+ }
+ if len(arr) == 0 {
+ *it = nil
+ return nil
+ }
+ *it = make(map[string]InstanceType, len(arr))
+ for _, t := range arr {
+ if _, ok := (*it)[t.Name]; ok {
+ return errDuplicateInstanceTypeName
+ }
+ (*it)[t.Name] = t
+ }
+ return nil
+ }
+ var hash map[string]InstanceType
+ err := json.Unmarshal(data, &hash)