Introduce HTTP exception into common

senlinclient/common/exc.py

@@ -23,5 +23,40 @@ class BaseException(Exception):
 class CommandError(BaseException):
     '''Invalid usage of CLI.'''
 
+
 class FileFormatError(BaseException):
     '''Illegal file format detected.'''
+
+
+class HTTPException(BaseException):
+    """Base exception for all HTTP-derived exceptions."""
+    code = 'N/A'
+
+    def __init__(self, message=None):
+        super(HTTPException, self).__init__(message)
+        try:
+            self.error = jsonutils.loads(message)
+            if 'error' not in self.error:
+                raise KeyError(_('Key "error" not exists'))
+        except KeyError:
+            # NOTE(jianingy): If key 'error' happens not exist,
+            # self.message becomes no sense. In this case, we
+            # return doc of current exception class instead.
+            self.error = {'error':
+                          {'message': self.__class__.__doc__}}
+        except Exception:
+            self.error = {'error':
+                          {'message': self.message or self.__class__.__doc__}}
+
+    def __str__(self):
+        message = self.error['error'].get('message', 'Internal Error')
+        if verbose:
+            traceback = self.error['error'].get('traceback', '')
+            return (_('ERROR: %(message)s\n%(traceback)s') %
+                    {'message': message, 'traceback': traceback})
+        else:
+            return _('ERROR: %s') % message
+
+
+class HTTPNotFound(HTTPException):
+    code = 404