[NEAT-488]😎 Session exceptions (#670)

* refactor: added shell for new exception classÃ

* refactor: setup decorator

* refactor; using neat session

cognite/neat/_session/_base.py

@@ -16,8 +16,10 @@
 from ._read import ReadAPI
 from ._state import SessionState
 from ._to import ToAPI
+from .exceptions import intercept_session_exceptions
 
 
+@intercept_session_exceptions
 class NeatSession:
     def __init__(
         self,

cognite/neat/_session/_state.py

@@ -7,6 +7,8 @@
 from cognite.neat._rules.models.information._rules_input import InformationInputRules
 from cognite.neat._store import NeatGraphStore
 
+from .exceptions import NeatSessionError
+
 
 @dataclass
 class SessionState:
@@ -27,7 +29,7 @@ def store(self) -> NeatGraphStore:
     @property
     def input_rule(self) -> ReadRules:
         if not self.input_rules:
-            raise ValueError("No input rules provided")
+            raise NeatSessionError("No input data model available. Try using [bold].read[/bold] to load a data model.")
         return self.input_rules[-1]
 
     @property
@@ -41,7 +43,9 @@ def information_input_rule(self) -> ReadRules | None:
     @property
     def last_verified_rule(self) -> VerifiedRules:
         if not self.verified_rules:
-            raise ValueError("No verified rules provided")
+            raise NeatSessionError(
+                "No data model available to verify. Try using  [bold].read[/bold] to load a data model."
+            )
         return self.verified_rules[-1]
 
     @property

cognite/neat/_session/exceptions.py

@@ -0,0 +1,42 @@
+import functools
+from collections.abc import Callable
+from typing import Any
+
+try:
+    from rich import print
+
+    _PREFIX = "[bold red][ERROR][/bold red]"
+except ImportError:
+    _PREFIX = "[ERROR]"
+
+
+class NeatSessionError(Exception):
+    """Base class for all exceptions raised by the NeatSession class."""
+
+    ...
+
+
+def _intercept_session_exceptions(func: Callable):
+    @functools.wraps(func)
+    def wrapper(*args: Any, **kwargs: Any):
+        try:
+            return func(*args, **kwargs)
+        except NeatSessionError as e:
+            action = func.__name__
+            print(f"{_PREFIX} Cannot {action}: {e}")
+
+    return wrapper
+
+
+def intercept_session_exceptions(cls: type):
+    to_check = [cls]
+    while to_check:
+        cls = to_check.pop()
+        for attr_name in dir(cls):
+            if not attr_name.startswith("_"):
+                attr = getattr(cls, attr_name)
+                if callable(attr):
+                    setattr(cls, attr_name, _intercept_session_exceptions(attr))
+                elif isinstance(attr, type):
+                    to_check.append(attr)
+    return cls

docs/CHANGELOG.md

@@ -29,6 +29,7 @@ Changes are grouped as follows:
 - Transformation is now generated for every RDF based rules importer
 
 ### Added
+- Added `NeatSession`
 - Rules exporter that produces a spreadsheet template for instance creation based on definition of classes in the rules
 - Rules transformer which converts information rules entities to be DMS compliant
 - Rules transformer `RuleMapping` that maps rules from one data model to another
@@ -43,7 +44,7 @@ Changes are grouped as follows:
 - Required `env_file_name` explicitly set in the `get_cognite_client` function. This is to avoid loading the wrong
   environment file by accident when running the function in a notebook.
 - `NeatIssue` are no longer immutable. This is to comply with the expectation of Exceptions in Python.
-
+- [BREAKING] All `NEAT` former public methods are now private. Only `NeatSession` is public.
 
 ## [0.92.3] - 17-09-24
 ### Fixed