pynml.manager

topology manager module.

Classes

• NMLManager: NML namespace manager.
• ExtendedNMLManager: Extended NMLManager object.

class pynml.manager.NMLManager(name=u'NML Namespace', **kwargs)

NML namespace manager.

Parameters:

name (str) – Name of this namespace.

Variables:

• namespace – OrderedDict with all NML objects registered. Use register_object() to register new objects.
• metadata – Store all kwargs passed to the constructor.

Inheritance

export_graphviz()

Export current namespace as a Graphviz graph.

Return type:str Returns:The current NML namespace in Graphviz graph notation.

export_nml(pretty=True)

Export current namespace as a NML XML format.

Parameters:pretty – Pretty print the output XML. Return type:str Returns:The current NML namespace in NML XML format.

get_object(identifier)

Get an object from this namespace by it’s unique identifier.

Parameters:identifier (str) – Object unique identifier. Return type:NMLObject Returns:The object with given identifier, or None if not found.

register_object(obj)

Register a NML object into the namespace managed by this Manager.

Parameters:obj (NetworkObject) – Object to register into the namespace. Raises:Exception – If object already in namespace.

save_graphviz(path, keep_gv=False)

Plot this namespace using Graphviz.

To use this function the following must be considered:

• The path must be a path to a filename in the format expected, for example, if a .svg file is expected the path must end with a .svg. If no format is provided an exception is raised.
• The output file will be overriden. If case of permissions or IO error and exception is raised.
• This function will call the dot binary by itself if found (using py:func:distutils.spawn.find_executable); if not, an exception is raised.
• If the output parent directories does not exists this function will try to create them using py:func:os.makedirs.

Parameters:

• path (str) – Path to save the rendered graphviz file.
• keep_gv (bool) – Keep the .gv file with the source of the graph. This file will live in the same directory of the output file with the same name but with the .gv.

Return type:

str o None

Returns:

Path to .gv file is keep_gv is True, else None.

save_nml(path, pretty=True)

Write NML XML file of the current namespace.

To use this function the following must be considered:

• The output file will be overriden. If case of permissions or IO error and exception is raised.
• If the output parent directories does not exists this function will try to create them using py:func:os.makedirs.

Parameters:

• path (str) – Path to save the exported XML of the NML namespace.
• pretty (bool) – Pretty print the output XML.

class pynml.manager.ExtendedNMLManager(**kwargs)

Extended NMLManager object.

This object provides a additional helper interface that allow to easily create common objects in a topology, their relations and iterate over them. In particular, this object does the following assumptions that are not part of the NML specification:

• A pynml.nml.BidirectionalPort is related to a single pynml.nml.Node.
• A pynml.nml.BidirectionalLink is related to a single pynml.nml.BidirectionalPort.

If the above assumptions aren’t true for your topologies please use the standard NMLManager or implement your own subclass.

The original proposed name for this class was NMLManagerWithCommonHelpersThatMakeSeveralAssumptions, but it was too long.

Inheritance

bilinks()

Iterate over all registered pynml.nml.BidirectionalLink s in the namespace.

This iterates the bilinks in the order as they were added into the namespace.

Returns:An iterator to all bilinks in the namespace. The iterator is a tuple of the form: ((pynml.nml.Node A, pynml.nml.BidirectionalPort A), (pynml.nml.Node B, pynml.nml.BidirectionalPort B), pynml.nml.BidirectionalLink).

biports()

Iterate over all registered pynml.nml.BidirectionalPort s in the namespace.

This iterates the biports in the order as they were added into the namespace.

Returns:An iterator to all biports in the namespace. The iterator is a tuple (pynml.nml.Node, pynml.nml.BidirectionalPort).

create_bilink(biport_a, biport_b, **kwargs)

Helper to create and register a pynml.nml.BidirectionalLink.

All keyword arguments are passed as is to the pynml.nml.BidirectionalLink constructor. This helper also creates all intermediate directed sink and source sublinks and relates them to the inbound and outbound subports.

Return type:pynml.nml.BidirectionalLink Returns:A new pynml.nml.BidirectionalLink already registered into the namespace and with sublinks already related.

create_biport(node, **kwargs)

Helper to create and register a pynml.nml.BidirectionalPort.

All keyword arguments are passed as is to the pynml.nml.BidirectionalPort constructor. This helper also creates all intermediate directed inbound and outbound subports and relates them to the node. The node argument is related to those subports too.

Return type:pynml.nml.BidirectionalPort Returns:A new pynml.nml.BidirectionalPort already registered into the namespace and with subports already related.

create_environment(**kwargs)

Helper to create and register a pynml.nml.Environment.

All keyword arguments are passed as is to the pynml.nml.Environment constructor.

Return type:pynml.nml.Environment Returns:A new pynml.nml.Environment already registered into the namespace.

create_node(**kwargs)

Helper to create and register a pynml.nml.Node.

All keyword arguments are passed as is to the pynml.nml.Node constructor.

Return type:pynml.nml.Node Returns:A new pynml.nml.Node already registered into the namespace.

environment

Returns the environment :class: pynml.nml.Environment

export_graphviz()

Graphiz export override. See NMLManager.export_graphviz().

nodes()

Iterate over all registered pynml.nml.Node s in the namespace.

This iterates the nodes in the order as they were added into the namespace.

Returns:An iterator to all nodes in the namespace.