Config

A configuration file is useful when you want to perform a measurement.

Config

Config(source: XMLSource)

Load a configuration file.

Parameters:

Name	Type	Description	Default
source	XMLSource	A path-like or file-like object containing the configuration data.	required

Source code in src/msl/equipment/config.py

def __init__(self, source: XMLSource) -> None:  # noqa: C901
    """Load a configuration file.

    Args:
        source: A [path-like][path-like object] or [file-like][file-like object]
            object containing the configuration data.
    """
    logger.debug("load configuration %s", source)
    self._source: XMLSource = source
    self._root: Element[str] = parse(source).getroot()  # noqa: S314
    self._registers: dict[str, Register] | None = None
    self._config_equipment: ConfigEquipment = ConfigEquipment(self)

    element = self.find("d2xx_library")
    if element is not None and element.text:
        os.environ["D2XX_LIBRARY"] = element.text
        logger.debug("update D2XX_LIBRARY=%s", element.text)

    element = self.find("gpib_library")
    if element is not None and element.text:
        os.environ["GPIB_LIBRARY"] = element.text
        logger.debug("update GPIB_LIBRARY=%s", element.text)

    element = self.find("pyvisa_library")
    if element is not None and element.text:
        os.environ["PYVISA_LIBRARY"] = element.text
        logger.debug("update PyVISA_LIBRARY=%s", element.text)

    path_elements = self.findall("path")
    if path_elements:
        paths: list[str] = []
        os_paths: set[str] = set(os.environ["PATH"].split(os.pathsep))
        for element in path_elements:
            path = element.text
            if not path or not os.path.isdir(path):  # noqa: PTH112
                logger.warning("skipped append to PATH: %r", path)
            elif element.attrib.get("recursive", "false").lower() == "true":
                for directory, _, _ in os.walk(path):
                    if directory not in os_paths and directory not in paths:
                        paths.append(directory)
                        logger.debug("append to PATH: %r", path)
            elif path not in os_paths and path not in paths:
                paths.append(path)
                logger.debug("append to PATH: %r", path)

        os.environ["PATH"] += os.pathsep + os.pathsep.join(paths)

    for element in self.findall("connections"):
        connections.add(*_sources(element.text, "connections"))

equipment property

equipment: ConfigEquipment

Returns the <equipment/> elements in the configuration file like a sequence of Equipment items.

Using the returned object you can access Equipment items by index (based on the order that <equipment/> elements are defined in the configuration file), by the eid attribute value or by the name attribute value. You can also iterate over the Equipment items in the sequence.

See here for examples.

path property

path: str

The path to the configuration file.

registers property

registers: dict[str, Register]

Returns all equipment registers that are specified in the configuration file.

The key in the returned dict is the team value of the corresponding Register.

root property

root: Element[str]

The root element (the first node) in the configuration file.

attrib

attrib(path: str) -> dict[str, bool | float | str]

Get the attributes of the first matching element by tag name or path.

If possible, the value is converted to a bool (true or false case-insensitive), an int or a float, otherwise the value remains a str.

Parameters:

Name	Type	Description	Default
path	str	Either an element tag name or an XPath.	required

Returns:

Type	Description
dict[str, bool | float | str]	The attributes of the matching path element.

Source code in src/msl/equipment/config.py

def attrib(self, path: str) -> dict[str, bool | float | str]:
    """Get the attributes of the first matching element by tag name or path.

    If possible, the value is converted to a [bool][] (`true` or `false` case-insensitive),
    an [int][] or a [float][], otherwise the value remains a [str][].

    Args:
        path: Either an element tag name or an XPath.

    Returns:
        The attributes of the matching `path` element.
    """
    element = self.find(path)
    if element is None:
        return {}
    return {k: to_primitive(v) for k, v in element.attrib.items()}

find

find(path: str) -> Element[str] | None

Find the first matching element by tag name or path.

Parameters:

Name	Type	Description	Default
path	str	Either an element tag name or an XPath.	required

Returns:

Type	Description
Element[str] | None	The element or None if an element was not found at path.

Source code in src/msl/equipment/config.py

def find(self, path: str) -> Element[str] | None:
    """Find the first matching element by tag name or path.

    Args:
        path: Either an element tag name or an XPath.

    Returns:
        The element or `None` if an element was not found at `path`.
    """
    return self._root.find(path)

findall

findall(path: str) -> list[Element[str]]

Find all matching sub-elements by tag name or path.

Parameters:

Name	Type	Description	Default
path	str	Either an element tag name or an XPath.	required

Returns:

Type	Description
list[Element[str]]	All matching elements in document order.

Source code in src/msl/equipment/config.py

def findall(self, path: str) -> list[Element[str]]:
    """Find all matching sub-elements by tag name or path.

    Args:
        path: Either an element tag name or an XPath.

    Returns:
        All matching elements in document order.
    """
    return self._root.findall(path)

value

value(path: str, default: None = None) -> bool | float | str | None

value(path: str, default: bool) -> bool

value(path: str, default: int) -> int

value(path: str, default: float) -> float

value(path: str, default: str) -> str

value(
    path: str, default: bool | float | str | None = None
) -> bool | float | str | None

Gets the value (text) associated with the first matching element.

If possible, the value is converted to a bool (true or false case-insensitive), an int or a float, otherwise the value remains a str.

Parameters:

Name	Type	Description	Default
path	str	Either an element tag name or an XPath.	required
default	bool | float | str | None	The default value if an element cannot be found.	None

Returns:

Type	Description
bool | float | str | None	The value of the element or default if an element was not found at path.

Source code in src/msl/equipment/config.py

def value(self, path: str, default: bool | float | str | None = None) -> bool | float | str | None:  # noqa: FBT001
    """Gets the value (text) associated with the first matching element.

    If possible, the value is converted to a [bool][] (`true` or `false` case-insensitive),
    an [int][] or a [float][], otherwise the value remains a [str][].

    Args:
        path: Either an element tag name or an XPath.
        default: The default value if an element cannot be found.

    Returns:
        The value of the element or `default` if an element was not found at `path`.
    """
    element = self.find(path)
    if element is None:
        return default
    if element.text is None:
        return None
    return to_primitive(element.text)

ConfigEquipment

ConfigEquipment(cfg: Config)

Access <equipment/> elements in a configuration file like a sequence of Equipment items.

Parameters:

Name	Type	Description	Default
cfg	Config	The configuration instance.	required

Source code in src/msl/equipment/config.py

def __init__(self, cfg: Config) -> None:
    """Access `<equipment/>` elements in a configuration file like a sequence of [Equipment][] items.

    Args:
        cfg: The configuration instance.
    """
    self._cfg: Config = cfg
    self._elements: list[Element[str]] = cfg.findall("equipment")
    self._equipment: dict[str, Equipment] = {}  # key=eid
    self._index_map: dict[int, str] = {i: e.attrib["eid"] for i, e in enumerate(self._elements)}
    self._name_map: dict[str, str] = {
        e.attrib["name"]: e.attrib["eid"] for e in self._elements if e.attrib.get("name")
    }

eids property

eids: tuple[str, ...]

Returns the value of the eid attribute for each <equipment/> element in a configuration file.

names property

names: tuple[str, ...]

Returns the value of the name attribute for each <equipment/> element in a configuration file.