[proxy] all request modification is done through map[string]interface{}

That way we are less likely fall victim to go-dockerclient, or the API changing.

proxy/json.go

@@ -13,12 +13,13 @@ func (e *UnmarshalWrongTypeError) Error() string {
 	return fmt.Sprintf("Wrong type for %s field, expected %s, but got %T", e.Field, e.Expected, e.Got)
 }
 
-// For parsing json objects. Look up (or create) a child object in the given map.
-func lookupObject(m map[string]interface{}, key string) (map[string]interface{}, error) {
-	iface, ok := m[key]
+type jsonObject map[string]interface{}
+
+func (j jsonObject) Object(key string) (jsonObject, error) {
+	iface, ok := j[key]
 	if !ok || iface == nil {
-		result := map[string]interface{}{}
-		m[key] = result
+		result := jsonObject{}
+		j[key] = result
 		return result, nil
 	}
 
@@ -27,12 +28,20 @@ func lookupObject(m map[string]interface{}, key string) (map[string]interface{},
 		return nil, &UnmarshalWrongTypeError{key, "object", iface}
 	}
 
-	return result, nil
+	return jsonObject(result), nil
 }
 
 // For parsing json objects. Look up (or create) a string in the given map.
-func lookupString(m map[string]interface{}, key string) (string, error) {
-	iface, ok := m[key]
+func (j jsonObject) String(key string, ks ...string) (string, error) {
+	if len(ks) > 0 {
+		j, err := j.Object(key)
+		if err != nil {
+			return "", err
+		}
+		return j.String(ks[0], ks[1:]...)
+	}
+
+	iface, ok := j[key]
 	if !ok || iface == nil {
 		return "", nil
 	}
@@ -44,3 +53,27 @@ func lookupString(m map[string]interface{}, key string) (string, error) {
 
 	return result, nil
 }
+
+// For parsing json objects. Look up (or create) a string array in the given map.
+func (j jsonObject) StringArray(key string) ([]string, error) {
+	iface, ok := j[key]
+	if !ok || iface == nil {
+		return nil, nil
+	}
+
+	switch o := iface.(type) {
+	case []string:
+		return o, nil
+	case []interface{}:
+		result := []string{}
+		for _, s := range o {
+			if s, ok := s.(string); ok {
+				result = append(result, s)
+			} else {
+				return nil, &UnmarshalWrongTypeError{key, "array of strings", iface}
+			}
+		}
+		return result, nil
+	}
+	return nil, &UnmarshalWrongTypeError{key, "array of strings", iface}
+}