topology.manager

topology manager module.

This module takes care of understanding the topology defined in the test suite, commanding its construction to appropriate topology platform plugin and finally commanding its destruction to the plugin also.

Classes

• TopologyManager: Main Topology Manager object.

class topology.manager.TopologyManager(engine='debug', **kwargs)

Main Topology Manager object.

This object is responsible to build a topology given a description.

There is three options to build a topology:

• Using the simplified textual description using a Graphviz like syntax. To use this option call the parse().

• Using a basic Python dictionary to load the description of the topology. To use this option call the load().

• Build a full NML topology using NML objects and relations and register all the objects in the namespace using the embedded pynml.manager.ExtendedNMLManager, for example:

  mgr = TopologyManager()
  sw1 = mgr.create_node(name='My Switch 1')
  sw2 = mgr.create_node(name='My Switch 2')
  sw1p1 = mgr.create_biport(sw1)
  # ...
  

  See pynml.manager.ExtendedNMLManager for more information of this usage.

Parameters:engine (str) – Name of the platform engine to build the topology. See platforms() for how to get and discover available platforms.

Inheritance

build()

Build the topology hold by this manager.

This method instance the platform engine and request the build of the topology defined.

get(identifier)

Get a platform engine with given identifier.

Parameters:identifier (str) – The node identifier. Return type:A subclass of topology.platforms.node.BaseNode Returns:The engine node implementing the communication with the node.

is_built()

Check if the current topology was built.

Return type:bool Returns:True if the topology was successfully built.

load(dictmeta, inject=None)

Load a topology description in a dictionary format.

Dictionary format:

{
    'nodes': [
        {
            'nodes': ['sw1', 'hs1', ...],
            'attributes': {...}
        },
    ],
    'ports': [
        {
            'ports': [('sw1', '1'), ('hs1', '1'), ...],
            'attributes': {...}
        }
    ]
    'links': [
        {
            'endpoints': (('sw1', '1'), ('hs1', '1')),
            'attributes': {...}
        },
    ]
}

Parameters:

• dictmeta (dict) – The dictionary to load the topology from.
• inject (dict) – An attributes injection sub-dictionary as defined by parse_attribute_injection().

parse(txtmeta, load=True, inject=None)

Parse a textual topology meta-description.

For a description of the textual format see pyszn package documentation.

Parameters:

• txtmeta (str) – The textual meta-description of the topology.
• load (bool) – If True (the default) call load() immediately after parse.
• inject (dict) – An attributes injection sub-dictionary as defined by parse_attribute_injection().

relink(link_id)

Relink back a link specified in the topology.

Parameters:link_id (str) – Link identifier to be recreated.

unbuild()

Undo the topology.

This removes all references to the engine nodes and request the platform to destroy the topology.

unlink(link_id)

Unlink (break) a link specified in the topology.

Parameters:link_id (str) – Link identifier to be recreated.