1 files changed, 63 insertions, 0 deletions
diff --git a/python/knot_resolver/utils/modeling/exceptions.py b/python/knot_resolver/utils/modeling/exceptions.py
new file mode 100644
index 00000000..478f5488
--- /dev/null
+++ b/python/knot_resolver/utils/modeling/exceptions.py
@@ -0,0 +1,63 @@
+from typing import Iterable, List
+
+from knot_resolver import KresBaseException
+
+
+class DataModelingBaseException(KresBaseException):
+    """
+    Base class for all exceptions used in modelling.
+    """
+
+
+class DataParsingError(DataModelingBaseException):
+    pass
+
+
+class DataDescriptionError(DataModelingBaseException):
+    pass
+
+
+class DataValidationError(DataModelingBaseException):
+    def __init__(self, msg: str, tree_path: str, child_exceptions: "Iterable[DataValidationError]" = tuple()) -> None:
+        super().__init__(msg)
+        self._tree_path = tree_path.replace("_", "-")
+        self._child_exceptions = child_exceptions
+
+    def where(self) -> str:
+        return self._tree_path
+
+    def msg(self):
+        return f"[{self.where()}] {super().__str__()}"
+
+    def recursive_msg(self, indentation_level: int = 0) -> str:
+        msg_parts: List[str] = []
+
+        if indentation_level == 0:
+            indentation_level += 1
+            msg_parts.append("Configuration validation error detected:")
+
+        INDENT = indentation_level * "\t"
+        msg_parts.append(f"{INDENT}{self.msg()}")
+
+        for c in self._child_exceptions:
+            msg_parts.append(c.recursive_msg(indentation_level + 1))
+        return "\n".join(msg_parts)
+
+    def __str__(self) -> str:
+        return self.recursive_msg()
+
+
+class AggregateDataValidationError(DataValidationError):
+    def __init__(self, object_path: str, child_exceptions: "Iterable[DataValidationError]") -> None:
+        super().__init__("error due to lower level exceptions", object_path, child_exceptions)
+
+    def recursive_msg(self, indentation_level: int = 0) -> str:
+        inc = 0
+        msg_parts: List[str] = []
+        if indentation_level == 0:
+            inc = 1
+            msg_parts.append("Configuration validation errors detected:")
+
+        for c in self._child_exceptions:
+            msg_parts.append(c.recursive_msg(indentation_level + inc))
+        return "\n".join(msg_parts)