feat: pretty print errors on scan history access

bec_ipython_client/bec_ipython_client/main.py

@@ -24,7 +24,7 @@
 from bec_ipython_client.signals import OperationMode, ScanInterruption, SigintHandler
 from bec_lib import plugin_helper
 from bec_lib.alarm_handler import AlarmBase
-from bec_lib.bec_errors import DeviceConfigError, ExceptionWithErrorInfo
+from bec_lib.bec_errors import BECError, DeviceConfigError, ExceptionWithErrorInfo
 from bec_lib.bec_service import parse_cmdline_args
 from bec_lib.callback_handler import EventType
 from bec_lib.client import BECClient
@@ -214,44 +214,18 @@ def show_last_alarm(self, offset: int = 0):
         except IndexError:
             print("No alarm has been raised in this session.")
             return
-
-        console = Console()
-
-        # --- HEADER ---
-        header = Text()
-        header.append("Alarm Raised\n", style="bold red")
-        header.append(f"Severity: {alarm.severity.name}\n", style="bold")
-        header.append(f"Type: {alarm.alarm_type}\n", style="bold")
-        if alarm.alarm.info.device:
-            header.append(f"Device: {alarm.alarm.info.device}\n", style="bold")
-
-        console.print(Panel(header, title="Alarm Info", border_style="red", expand=False))
-
-        # --- SHOW SUMMARY
-        if alarm.alarm.info.compact_error_message:
-            console.print(
-                Panel(
-                    Text(alarm.alarm.info.compact_error_message, style="yellow"),
-                    title="Summary",
-                    border_style="yellow",
-                    expand=False,
-                )
-            )
-
-        # --- SHOW FULL TRACEBACK
-        tb_str = alarm.alarm.info.error_message
-        if tb_str:
-            try:
-                console.print(tb_str)
-            except Exception:
-                # fallback in case msg is not a traceback
-                console.print(Panel(tb_str, title="Message", border_style="cyan"))
+        if hasattr(alarm, "print_details"):
+            alarm.print_details()
+            return
+        if hasattr(alarm, "pretty_print"):
+            alarm.pretty_print()
+            return
 
 
 def _ip_exception_handler(
     self, etype, evalue, tb, tb_offset=None, parent: BECIPythonClient = None, **kwargs
 ):
-    if issubclass(etype, AlarmBase):
+    if issubclass(etype, (AlarmBase, BECError)):
         parent._alarm_history.append((etype, evalue, tb, tb_offset))
         log_console_error(etype, evalue, tb)
         print("\x1b[31m BEC alarm:\x1b[0m")

bec_lib/bec_lib/alarm_handler.py

@@ -9,14 +9,10 @@
 from collections import deque
 from typing import TYPE_CHECKING
 
-from rich.console import Console, Group
-from rich.panel import Panel
-from rich.syntax import Syntax
-from rich.text import Text
-
 from bec_lib.endpoints import MessageEndpoints
 from bec_lib.logger import bec_logger
 from bec_lib.utils import threadlocked
+from bec_lib.utils.error_pretty_print import AlarmPrettyPrinter
 
 if TYPE_CHECKING:  # pragma: no cover
     from bec_lib import messages
@@ -42,6 +38,7 @@ def __init__(self, alarm: messages.AlarmMessage, severity: Alarms, handled=False
         self.severity = severity
         self.handled = handled
         self.alarm_type = alarm.info.exception_type
+        self._pretty_printer = AlarmPrettyPrinter(alarm.info, severity)
         super().__init__(self.alarm.content)
 
     def __str__(self) -> str:
@@ -52,38 +49,10 @@ def __str__(self) -> str:
         )
 
     def pretty_print(self) -> None:
-        """
-        Use Rich to pretty print the alarm message,
-        following the same logic used in __str__().
-        """
-        console = Console()
+        self._pretty_printer.pretty_print()
 
-        msg = self.alarm.info.compact_error_message or self.alarm.info.error_message
-
-        text = Text()
-        text.append(f"{self.alarm_type} | ", style="bold")
-        text.append(f"Severity {self.severity.name}", style="bold yellow")
-        if self.alarm.info.device:
-            text.append(f" | Device {self.alarm.info.device}\n", style="bold")
-        text.append("\n")
-
-        renderables = []
-        # Format message inside a syntax box if it looks like traceback
-        if "Traceback (most recent call last):" in msg:
-            renderables.append(Syntax(msg.strip(), "python", word_wrap=True))
-        else:
-            renderables.append(Text(msg.strip()))
-
-        if self.alarm.info.device:
-            renderables.append(
-                Text(
-                    f"\n\nThe error is likely unrelated to BEC. Please check the device '{self.alarm.info.device}'.",
-                    style="bold",
-                )
-            )
-        body = Group(*renderables)
-
-        console.print(Panel(body, title=text, border_style="red", expand=True))
+    def print_details(self) -> None:
+        self._pretty_printer.print_details()
 
     def __eq__(self, other: object) -> bool:
         if not isinstance(other, AlarmBase):

bec_lib/bec_lib/bec_errors.py

@@ -7,10 +7,27 @@
 import traceback
 from typing import TYPE_CHECKING
 
-if TYPE_CHECKING:
+from bec_lib.utils.error_pretty_print import ErrorInfoPrettyPrinter
+
+if TYPE_CHECKING:  # pragma: no cover
     from bec_lib import messages
 
 
+class BECError(Exception):
+    """Base class for all BEC exceptions"""
+
+    def __init__(self, message: str, error_info: messages.ErrorInfo) -> None:
+        super().__init__(message)
+        self.error_info = error_info
+        self._pretty_printer = ErrorInfoPrettyPrinter(error_info)
+
+    def pretty_print(self) -> None:
+        self._pretty_printer.pretty_print()
+
+    def print_details(self) -> None:
+        self._pretty_printer.print_details()
+
+
 class ScanAbortion(Exception):
     """Scan abortion exception"""
 
@@ -41,46 +58,24 @@ class ExceptionWithErrorInfo(Exception):
     def __init__(self, error_info: messages.ErrorInfo):
         super().__init__(error_info.error_message)
         self.error_info = error_info
+        self._pretty_printer = ErrorInfoPrettyPrinter(error_info)
 
     def __str__(self) -> str:
         msg = self.error_info.compact_error_message
         return f"{self.__class__.__name__}: {msg}" if msg else super().__str__()
 
     def pretty_print(self) -> None:
-        """
-        Use Rich to pretty print the error message,
-        following the same logic used in __str__().
-        """
-        from rich.console import Console, Group
-        from rich.panel import Panel
-        from rich.syntax import Syntax
-        from rich.text import Text
-
-        console = Console()
-        msg = self.error_info.compact_error_message or self.error_info.error_message
-
-        text = Text()
-        text.append(f"{self.__class__.__name__}", style="bold")
-        text.append("\n")
+        self._pretty_printer.pretty_print()
 
-        renderables = []
-        # Format message inside a syntax box if it looks like traceback
-        if "Traceback (most recent call last):" in msg:
-            renderables.append(Syntax(msg.strip(), "python", word_wrap=True))
-        else:
-            renderables.append(Text(msg.strip()))
-
-        body = Group(*renderables)
-
-        console.print(Panel(body, title=text, border_style="red", expand=True))
+    def print_details(self) -> None:
+        self._pretty_printer.print_details()
 
 
 class ScanInputValidationError(ExceptionWithErrorInfo):
     """Scan input validation error"""
 
     def __init__(self, error_info: messages.ErrorInfo):
         super().__init__(error_info)
-        self.error_info = error_info
 
     @classmethod
     def with_error_info(cls, message: str) -> ScanInputValidationError:

bec_lib/bec_lib/messages.py

@@ -560,6 +560,7 @@ class ErrorInfo(BaseModel):
     compact_error_message: str | None
     exception_type: str
     device: str | list[str] | None = None
+    context: str | None = None
 
 
 class DeviceInstructionResponse(BECMessage):

bec_lib/bec_lib/scan_history.py

@@ -6,14 +6,16 @@
 
 import os
 import threading
+import traceback
 from typing import TYPE_CHECKING
 
+from bec_lib import messages
+from bec_lib.bec_errors import BECError
 from bec_lib.callback_handler import EventType
 from bec_lib.endpoints import MessageEndpoints
 from bec_lib.scan_data_container import ScanDataContainer
 
 if TYPE_CHECKING:  # pragma: no cover
-    from bec_lib import messages
     from bec_lib.client import BECClient
 
 
@@ -140,7 +142,27 @@ def __len__(self) -> int:
     def __getitem__(self, index: int | slice) -> ScanDataContainer | list[ScanDataContainer]:
         with self._scan_data_lock:
             if isinstance(index, int):
-                target_id = self._scan_ids[index]
+                try:
+                    target_id = self._scan_ids[index]
+                except IndexError:
+                    if len(self._scan_ids) == 0:
+                        compact_msg = (
+                            f"ScanHistory is empty. This may be due to no scans being "
+                            f"run yet or the current user {os.getlogin()} not having access to the data files."
+                        )
+                    else:
+                        compact_msg = (
+                            f"Index {index} out of range for ScanHistory of length {len(self)}"
+                        )
+                    error_info = messages.ErrorInfo(
+                        error_message=traceback.format_exc(),
+                        compact_error_message=compact_msg,
+                        exception_type="IndexError",
+                        context="ScanHistory",
+                        device=None,
+                    )
+                    raise BECError(compact_msg, error_info)
+
                 return self.get_by_scan_id(target_id)
             if isinstance(index, slice):
                 return [self.get_by_scan_id(scan_id) for scan_id in self._scan_ids[index]]