🎨 Work on import error handling

- Generic ErrorProducer class
- Importer and managers are error producers
- SGDB Auth friendly error
- Bad source location friendly errors (data, config, cache)
- Removed unused decorators

src/errors/error_producer.py

@@ -0,0 +1,28 @@
+from threading import Lock
+
+
+class ErrorProducer:
+    """
+    A mixin for objects that produce errors.
+
+    Specifies the report_error and collect_errors methods in a thread-safe manner.
+    """
+
+    errors: list[Exception] = None
+    errors_lock: Lock = None
+
+    def __init__(self) -> None:
+        self.errors = []
+        self.errors_lock = Lock()
+
+    def report_error(self, error: Exception):
+        """Report an error"""
+        with self.errors_lock:
+            self.errors.append(error)
+
+    def collect_errors(self) -> list[Exception]:
+        """Collect and remove the errors produced by the object"""
+        with self.errors_lock:
+            errors = self.errors.copy()
+            self.errors.clear()
+        return errors

src/errors/friendly_error.py

@@ -0,0 +1,47 @@
+from typing import Iterable
+
+
+class FriendlyError(Exception):
+    """
+    An error that is supposed to be shown to the user in a nice format
+
+    Use `raise ... from ...` to preserve context.
+    """
+
+    title_format: str
+    title_args: Iterable[str]
+    subtitle_format: str
+    subtitle_args: Iterable[str]
+
+    @property
+    def title(self) -> str:
+        """Get the gettext translated error title"""
+        return _(self.title_format).format(self.title_args)
+
+    @property
+    def subtitle(self) -> str:
+        """Get the gettext translated error subtitle"""
+        return _(self.subtitle_format).format(self.subtitle_args)
+
+    def __init__(
+        self,
+        title: str,
+        subtitle: str,
+        title_args: Iterable[str] = None,
+        subtitle_args: Iterable[str] = None,
+    ) -> None:
+        """Create a friendly error
+
+        :param str title: The error's title, translatable with gettext
+        :param str subtitle: The error's subtitle, translatable with gettext
+        """
+        super().__init__()
+        if title is not None:
+            self.title_format = title
+        if subtitle is not None:
+            self.subtitle_format = subtitle
+        self.title_args = title_args if title_args else ()
+        self.subtitle_args = subtitle_args if subtitle_args else ()
+
+    def __str__(self) -> str:
+        return f"{self.title} - {self.subtitle}"