pydevDAG._structure module

pydevDAG._structure

Tools to build and manipulate graphs of device relationships.

class pydevDAG._structure.DMPartitionGraphs

Bases: object

Build graphs of relationships between device mapper devices and partitions.

classmethod complete(context)

Build a complete graph showing device mapper, partition relationships.

Parameters:context (Context) – a udev context Returns:a graph Return type:DiGraph

static congruence_graph(context, device)

Build a graph of congruence relation between device mapper devices and partition devices.

Parameters:

• context (Context) – a udev context
• device (Device) – the partition device

Returns:

a graph

Return type:

DiGraph

class pydevDAG._structure.Graph

Bases: object

Build a graph according to specifications.

static graph(context, name, classes)

Build a graph using the designated classes.

Parameters:

• context – a context
• name (str) – a name for the graph
• classes (list of type) – a list of graph classes

Returns:

a graph

Return type:

nx.DiGraph

class pydevDAG._structure.GraphMethods

Bases: object

Generic graph methods.

classmethod add_edges(graph, sources, targets, edge_type, source_node_type, target_node_type)

Add edges to graph from sources to targets.

Parameters:

• graph (DiGraph) – the graph
• sources (list of object) – source nodes
• targets (list of object) – target nodes
• edge_type (EdgeType) – type for edges
• source_node_type (NodeType) – type for source nodes
• target_node_type (NodeType) – type for target nodes

Nodes are device_paths of each device, as these uniquely identify the device.

classmethod add_nodes(graph, nodes, node_type)

Add nodes in nodes to graph.

Parameters:

• graph (DiGraph) – the graph
• nodes (list of object) – source nodes
• node_type (NodeType) – a node type

Nodes are device_paths of each device, as these uniquely identify the device.

static get_node_args(nodes, node_type)

Get node arguments, along with keys.

Parameters:

• nodes (list of object) – source nodes
• node_type (NodeType) – a node type

Returns:

arguments suitable for passing to add_nodes_from()

class pydevDAG._structure.PartitionGraphs

Bases: object

Build graphs of partition relationships.

classmethod complete(context)

Build a complete graph of all partitions.

Parameters:context (Context) – a udev context Returns:a graph Return type:DiGraph

static partition_graph(device)

Make a graph of partition relationships.

Parameters:device (Device) – the partition device Returns:a graph Return type:DiGraph

class pydevDAG._structure.SpindleGraphs

Bases: object

Build graphs of relationships with actual physical disks.

classmethod complete(context)

Build a complete graph showing path/spindle relationships.

Parameters:context (Context) – a udev context Returns:a graph Return type:DiGraph

static spindle_graph(device)

Make a graph of spindle relationships.

Parameters:device (Device) – the partition device Returns:a graph Return type:DiGraph

class pydevDAG._structure.SysfsBlockGraphs

Bases: object

Composes holders/slaves graphs for block devices.

static complete(context)

Build a complete graph showing all block devices.

Parameters:context (Context) – a udev context Returns:a graph Return type:DiGraph

class pydevDAG._structure.SysfsGraphs

Bases: object

Build sysfs graphs in various ways.

classmethod complete(context, **kwargs)

Build a complete graph showing all devices.

Parameters:

• context (Context) – a udev context
• kwargs – arguments for filtering the devices.

Returns:

a graph

Return type:

DiGraph

classmethod parents_and_children(context, device)

Make a graph of the parents and children of a device.

Parameters:

• context (Context) – the libudev context
• device (Device) – the device

Returns:

a graph

Return type:

DiGraph

static slaves_and_holders(context, device, recursive=True)

Make a graph of slaves and holders of a device.

Parameters:

• context (Context) – the libudev context
• device (Device) – the device
• recursive (bool) – True for recursive, False otherwise

Returns:

a graph

Return type:

DiGraph

class pydevDAG._structure.SysfsTraversal

Bases: object

Build simple graph from the holders or slaves of a given device.

classmethod do_level(graph, context, device, config)

Recursively defined function to generate a graph from device.

Parameters:

• graph (DiGraph) – the graph
• context (Context) – the libudev context
• device (Device) – the device
• config (SysfsTraversalConfig) – traversal configuration

classmethod holders(context, device, recursive=True)

Yield graph of slaves of device, including the device.

Parameters:

• context (Context) – the libudev context
• device (Device) – the device
• recursive (bool) – True for recursive, False otherwise

Returns:

a graph

Return type:

DiGraph

classmethod slaves(context, device, recursive=True)

Yield graph of slaves of device, including the device.

Parameters:

• context (Context) – the libudev context
• device (Device) – the device
• recursive (bool) – True for recursive, False otherwise

Returns:

a graph

Return type:

DiGraph

classmethod sysfs_traversal(context, device, config)

General graph of a sysfs traversal.

Parameters:

• context (Context) – the libudev context
• device (Device) – the device
• config (SysfsTraversalConfig) – traversal configuration

Returns:

a graph

Return type:

DiGraph

class pydevDAG._structure.SysfsTraversalConfig

Bases: tuple

SysfsTraversalConfig(recursive, slaves)

recursive

Alias for field number 0

slaves

Alias for field number 1