Introspection

class dbus_fast.introspection.Node(name: str = None, interfaces: List[Interface] = None, is_root: bool = True)

A class that represents a node in an object path in introspection data.

A node contains information about interfaces exported on this path and child nodes. A node can be converted to and from introspection XML exposed through the org.freedesktop.DBus.Introspectable standard DBus interface.

This class is an essential building block for a high-level DBus interface. This is the underlying data structure for the ProxyObject. A ServiceInterface definition is converted to this class to expose XML on the introspectable interface.

Variables:

  • interfaces (list(Interface)) – A list of interfaces exposed on this node.

  • nodes (list(Node)) – A list of child nodes.

  • name (str) – The object path of this node.

  • is_root (bool) – Whether this is the root node. False if it is a child node.

Raises:
static default(name: str = None) → Node

Create a Node with the default interfaces supported by this library.

The default interfaces include:

  • org.freedesktop.DBus.Introspectable

  • org.freedesktop.DBus.Peer

  • org.freedesktop.DBus.Properties

  • org.freedesktop.DBus.ObjectManager

static from_xml(element: Element, is_root: bool = False)

Convert an xml.etree.ElementTree.Element to a Node.

The element must be valid DBus introspection XML for a node.

Parameters:

  • element (xml.etree.ElementTree.Element) – The parsed XML element.

  • is_root (bool) – Whether this is the root node

Raises:
static parse(data: str) → Node

Parse XML data as a string into a Node.

The string must be valid DBus introspection XML.

Parameters:

data (str) – The XMl string.

Raises:
to_xml() → Element

Convert this Node into an xml.etree.ElementTree.Element.

tostring() → str

Convert this Node into a DBus introspection XML string.

class dbus_fast.introspection.Interface(name: str, methods: List[Method] = None, signals: List[Signal] = None, properties: List[Property] = None)

A class that represents a DBus interface exported on on object path.

Contains information about the methods, signals, and properties exposed on this interface.

Variables:

  • name (str) – The name of this interface.

  • methods (list(Method)) – A list of methods exposed on this interface.

  • signals (list(Signal)) – A list of signals exposed on this interface.

  • properties (list(Property)) – A list of properties exposed on this interface.

Raises:
static from_xml(element: Element) → Interface

Convert a xml.etree.ElementTree.Element into a Interface.

The element must be valid DBus introspection XML for an interface.

Parameters:

element (xml.etree.ElementTree.Element) – The parsed XML element.

Raises:
to_xml() → Element

Convert this Interface into an xml.etree.ElementTree.Element.

class dbus_fast.introspection.Property(name: str, signature: str, access: PropertyAccess = PropertyAccess.READWRITE)

A class that represents a DBus property exposed on an Interface.

Variables:

  • name (str) – The name of this property.

  • signature (str) – The signature string for this property. Must be a single complete type.

  • access (PropertyAccess) – Whether this property is readable and writable.

  • type (SignatureType) – The parsed type of this property.

Raises:

  • InvalidIntrospectionError - If the property is not a single complete type.

  • :class InvalidSignatureError <dbus_fast.InvalidSignatureError> - If the given signature is not valid.

  • class:

    InvalidMemberNameError <dbus_fast.InvalidMemberNameError> - If the member name is not valid.

from_xml()

Convert an xml.etree.ElementTree.Element to a Property.

The element must be valid DBus introspection XML for a property.

Parameters:

element (xml.etree.ElementTree.Element) – The parsed XML element.

Raises:
to_xml() → Element

Convert this Property into an xml.etree.ElementTree.Element.

class dbus_fast.introspection.Method(name: str, in_args: List[Arg] = [], out_args: List[Arg] = [])

A class that represents a method exposed on an Interface.

Variables:

  • name (str) – The name of this method.

  • in_args (list(Arg)) – A list of input arguments to this method.

  • out_args (list(Arg)) – A list of output arguments to this method.

  • in_signature (str) – The collected signature string of the input arguments.

  • out_signature (str) – The collected signature string of the output arguments.

Raises:
from_xml() → Method

Convert an xml.etree.ElementTree.Element to a Method.

The element must be valid DBus introspection XML for a method.

Parameters:

  • element (xml.etree.ElementTree.Element) – The parsed XML element.

  • is_root (bool) – Whether this is the root node

Raises:
to_xml() → Element

Convert this Method into an xml.etree.ElementTree.Element.

class dbus_fast.introspection.Signal(name: str, args: List[Arg] = None)

A class that represents a signal exposed on an interface.

Variables:

  • name (str) – The name of this signal

  • args (list(Arg)) – A list of output arguments for this signal.

  • signature (str) – The collected signature of the output arguments.

Raises:
from_xml()

Convert an xml.etree.ElementTree.Element to a Signal.

The element must be valid DBus introspection XML for a signal.

Parameters:

  • element (xml.etree.ElementTree.Element) – The parsed XML element.

  • is_root (bool) – Whether this is the root node

Raises:
to_xml() → Element

Convert this Signal into an xml.etree.ElementTree.Element.

class dbus_fast.introspection.Arg(signature: Union[SignatureType, str], direction: List[ArgDirection] = None, name: str = None)

A class that represents an input or output argument to a signal or a method.

Variables:

  • name (str) – The name of this arg.

  • direction (ArgDirection) – Whether this is an input or an output argument.

  • type (SignatureType) – The parsed signature type of this argument.

  • signature (str) – The signature string of this argument.

Raises:
from_xml(direction: ArgDirection) → Arg

Convert a xml.etree.ElementTree.Element into a Arg.

The element must be valid DBus introspection XML for an arg.

Parameters:

  • element (xml.etree.ElementTree.Element) – The parsed XML element.

  • direction (ArgDirection) – The direction of this arg. Must be specified because it can default to different values depending on if it’s in a method or signal.

Raises:
to_xml() → Element

Convert this Arg into an xml.etree.ElementTree.Element.