Merge pull request #258 from DiamondLightSource/fastcs-odin-dev

fastcs-odin developments

Author: GDYendell

src/fastcs/attributes.py

@@ -6,13 +6,13 @@
 
 from fastcs.attribute_io_ref import AttributeIORefT
 from fastcs.datatypes import ATTRIBUTE_TYPES, DataType, T
-from fastcs.logging import logger as _logger
+from fastcs.logging import bind_logger
 from fastcs.tracer import Tracer
 
 ONCE = float("inf")
 """Special value to indicate that an attribute should be updated once on start up."""
 
-logger = _logger.bind(logger_name=__name__)
+logger = bind_logger(logger_name=__name__)
 
 
 class Attribute(Generic[T, AttributeIORefT], Tracer):
@@ -171,6 +171,7 @@ async def update(self, value: T) -> None:
                 logger.opt(exception=e).error(
                     "On update callback failed", attribute=self, value=value
                 )
+                raise
 
     def add_on_update_callback(self, callback: AttrOnUpdateCallback[T]) -> None:
         """Add a callback to be called when the value of the attribute is updated
@@ -248,7 +249,8 @@ async def put(self, setpoint: T, sync_setpoint: bool = False) -> None:
         be rejected.
 
         To directly change the value of the attribute, for example from an update loop
-        that has read a new value from some underlying source, call the ``set`` method.
+        that has read a new value from some underlying source, call the ``update``
+        method.
 
         """
         setpoint = self._datatype.validate(setpoint)

src/fastcs/controller.py

@@ -128,13 +128,15 @@ def _validate_io(self, ios: Sequence[AttributeIO[T, AttributeIORefT]]):
     def add_attribute(self, name, attribute: Attribute):
         if name in self.attributes and attribute is not self.attributes[name]:
             raise ValueError(
-                f"Cannot add attribute {name}. "
-                f"Controller {self} has has existing attribute {name}"
+                f"Cannot add attribute {attribute}. "
+                f"Controller {self} has has existing attribute {name}: "
+                f"{self.attributes[name]}"
             )
         elif name in self.__sub_controller_tree.keys():
             raise ValueError(
-                f"Cannot add attribute {name}. "
-                f"Controller {self} has existing sub controller {name}"
+                f"Cannot add attribute {attribute}. "
+                f"Controller {self} has existing sub controller {name}: "
+                f"{self.__sub_controller_tree[name]}"
             )
 
         attribute.set_name(name)
@@ -145,13 +147,15 @@ def add_attribute(self, name, attribute: Attribute):
     def add_sub_controller(self, name: str, sub_controller: Controller):
         if name in self.__sub_controller_tree.keys():
             raise ValueError(
-                f"Cannot add sub controller {name}. "
-                f"Controller {self} has existing sub controller {name}"
+                f"Cannot add sub controller {sub_controller}. "
+                f"Controller {self} has existing sub controller {name}: "
+                f"{self.__sub_controller_tree[name]}"
             )
         elif name in self.attributes:
             raise ValueError(
-                f"Cannot add sub controller {name}. "
-                f"Controller {self} has existing attribute {name}"
+                f"Cannot add sub controller {sub_controller}. "
+                f"Controller {self} has existing attribute {name}: "
+                f"{self.attributes[name]}"
             )
 
         sub_controller.set_path(self.path + [name])

src/fastcs/logging/__init__.py

@@ -7,7 +7,7 @@
 from ._graylog import GraylogStaticFields as GraylogStaticFields
 from ._graylog import parse_graylog_env_fields as parse_graylog_env_fields
 from ._graylog import parse_graylog_static_fields as parse_graylog_static_fields
-from ._logging import LogLevel, _configure_logger
+from ._logging import Logger, LogLevel, _configure_logger
 
 logger = _logger.bind(logger_name="fastcs")
 """FastCS logger
@@ -50,13 +50,25 @@
 fastcs. Instead there is a ``Tracer`` class for verbose logging with fine-grained
 controls that can be enabled by the user at runtime.
 
-Use ``configure_logging`` to re-confi the logger at runtime. For more advanced
+Use ``configure_logging`` to re-configure the logger at runtime. For more advanced
 controls, configure the ``logger`` singleton directly.
 
 See the ``loguru`` docs for more information: https://loguru.readthedocs.io
 """
 
 
+def bind_logger(logger_name: str) -> Logger:
+    """Create a wrapper of the singleton fastcs logger with the given name bound
+
+    The name will be displayed in all log messages from the returned wrapper.
+
+    See the docstring for ``fastcs.logging.logger`` for more information.
+
+    """
+
+    return logger.bind(logger_name=logger_name)
+
+
 def configure_logging(
     level: LogLevel | None = None,
     graylog_endpoint: GraylogEndpoint | None = None,

src/fastcs/transport/epics/ca/ioc.py

@@ -10,7 +10,7 @@
 from fastcs.controller_api import ControllerAPI
 from fastcs.cs_methods import Command
 from fastcs.datatypes import DataType, T
-from fastcs.logging import logger as _logger
+from fastcs.logging import bind_logger
 from fastcs.tracer import Tracer
 from fastcs.transport.epics.ca.util import (
     builder_callable_from_attribute,
@@ -27,7 +27,7 @@
 
 
 tracer = Tracer(name=__name__)
-logger = _logger.bind(logger_name=__name__)
+logger = bind_logger(logger_name=__name__)
 
 
 class EpicsCAIOC:

src/fastcs/transport/epics/ca/util.py

@@ -31,6 +31,7 @@
 
 
 EPICS_ALLOWED_DATATYPES = (Bool, DataType, Enum, Float, Int, String, Waveform)
+EPICS_WAVEFORM_LENGTH = 256
 
 DATATYPE_FIELD_TO_RECORD_FIELD = {
     "prec": "PREC",
@@ -124,8 +125,10 @@ def cast_to_epics_type(datatype: DataType[T], value: T) -> object:
                 return datatype.index_of(datatype.validate(value))
             else:  # enum backed by string record
                 return datatype.validate(value).name
+        case String():
+            return value[: EPICS_WAVEFORM_LENGTH - 1]
         case datatype if issubclass(type(datatype), EPICS_ALLOWED_DATATYPES):
-            return datatype.validate(value)
+            return value
         case _:
             raise ValueError(f"Unsupported datatype {datatype}")