feat: add path utils for centralized path validation

Author: AlePouroullis

src/humanloop/path_utils.py

@@ -0,0 +1,39 @@
+from pathlib import Path
+from typing import Optional
+
+from humanloop.error import HumanloopRuntimeError
+
+
+def validate_no_extensions(path: str, allowed_extensions: Optional[list[str]] = None) -> str:
+    """Validates that path has no extensions (or only allowed ones) and returns path without extension."""
+    if "." in path:
+        parts = path.rsplit(".", 1)
+        extension = parts[1] if len(parts) > 1 else ""
+        path_without_extension = parts[0]
+        
+        if allowed_extensions and extension in allowed_extensions:
+            return path
+        
+        raise HumanloopRuntimeError(
+            f"Path '{path}' includes a file extension which is not supported in this context. "
+            f"Use the format without extensions: '{path_without_extension}'."
+        )
+    return path
+
+def validate_no_slashes(path: str) -> str:
+    """Validates that path has no leading/trailing slashes."""
+    if path != path.strip("/"):
+        raise HumanloopRuntimeError(
+            f"Invalid path: '{path}'. Path should not contain leading/trailing slashes. "
+            f"Valid example: 'path/to/resource'"
+        )
+    return path
+
+def validate_not_absolute(path: str, base_dir: Optional[str] = None) -> str:
+    """Validates that path is not absolute."""
+    if Path(path).is_absolute():
+        message = f"Absolute paths are not supported: '{path}'."
+        if base_dir:
+            message += f" Paths should be relative to '{base_dir}'."
+        raise HumanloopRuntimeError(message)
+    return path