msl.equipment.config module

Load an XML Configuration File.

msl.equipment.config.XMLType

An XML-document type that can be parsed.

alias of Union[str, bytes, PathLike, BinaryIO, TextIO]

class msl.equipment.config.Config(source: str | bytes | PathLike | BinaryIO | TextIO)

Bases: object

Load an XML Configuration File.

The purpose of the Configuration File is to define parameters that may be required during data acquisition and to access EquipmentRecord’s from an Equipment-Register Database and ConnectionRecord’s from a Connections Database.

The following table summarizes the XML elements that are used by MSL-Equipment which may be defined in a Configuration File:

XML Tag	Example Values	Description
demo_mode	true, false, True, False	Whether to open connections in demo mode. The value will set DEMO_MODE.
gpib_library	/opt/gpib/libgpib.so.0	The path to a GPIB library file. Required only if you want to use a specific file. The value will set GPIB_LIBRARY.
path	C:\Program Files\Company	A path that contains additional resources. Accepts a recursive=”true” attribute. The path(s) are appended to PATH and to os.environ['PATH']. A <path> element may be specified multiple times.
pyvisa_library	@ivi, @py, /opt/ni/libvisa.so.7	The PyVISA library to use. The value will set PyVISA_LIBRARY.

You are also encouraged to define your own application-specific elements within your Configuration File.

Parameters:

source – A filename or file object containing XML data.

GPIB_LIBRARY: str = ''

The path to a GPIB library file.

Setting this attribute is necessary only if you want to communicate with a GPIB device and the file is not automatically found or you want to use a different file than the default file.

PyVISA_LIBRARY: str = '@ivi'

The PyVISA backend library to use.

DEMO_MODE: bool = False

Whether to open connections in demo mode.

If enabled then the equipment does not need to be physically connected to a computer and the connection is simulated.

PATH: list[str] = []

Paths are also appended to os.environ['PATH'].

attrib(tag_or_path: str) → dict[str, Any]

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

The values are converted to the appropriate data type if possible. For example, if the text of the element is true it will be converted to True, otherwise the value will be kept as a str.

Parameters:

tag_or_path – Either an element tag name or an XPath.

Returns:

The attributes of the matching element.

database() → Database

A reference to the equipment and connection records in the database(s).

find(tag_or_path: str) → Element | None

Find the first matching element by tag name or path.

Parameters:

tag_or_path – Either an element tag name or an XPath.

Returns:

The element or None if no element was found.

findall(tag_or_path: str) → list[Element]

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

Parameters:

tag_or_path – Either an element tag name or an XPath.

Returns:

All matching elements in document order.

property path: str

The path to the configuration file.

property root: Element

The root element (the first node) in the XML document.

value(tag_or_path: str, default: Any = None) → Any

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

The value is converted to the appropriate data type if possible. For example, if the text of the element is true it will be converted to True.

Parameters:

• tag_or_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 no element was found.