source: fedd/federation/topdl.py @ eec716b

#!/usr/local/bin/python

class base:
    @staticmethod
    def init_class(c, arg):
        if isinstance(arg, dict):
            return c(**arg)
        elif isinstance(arg, c):
            return arg
        else:
            return None

    @staticmethod
    def make_list(a):
        if isinstance(a, basestring) or isinstance(a, dict): return [ a ]
        elif getattr(a, '__iter__', None): return a
        else: return [ a ]



class ConsistencyError(RuntimeError): pass

class Attribute(base):
    def __init__(self, attribute, value):
        self.attribute = attribute
        self.value = value

    def to_dict(self):
        return { 'attribute': self.attribute, 'value': self.value }

class Capacity(base):
    def __init__(self, rate, kind):
        self.rate = rate
        self.kind = kind

    def to_dict(self):
        return { 'rate': self.rate, 'kind': self.kind }

class Latency(base):
    def __init__(self, time, kind):
        self.time = time
        self.kind = kind

    def to_dict(self):
        return { 'time': self.time, 'kind': self.kind }

class Substrate(base):
    def __init__(self, name, capacity=None, latency=None, attribute=[]):
        self.name = name
        self.capacity = self.init_class(Capacity, capacity)
        self.latency = self.init_class(Latency, latency)
        self.attribute = [ self.init_class(Attribute, a) \
                for a in self.make_list(attribute) ]
        self.interfaces = [ ]

    def to_dict(self):
        rv = { 'name': self.name }
        if self.capacity:
            rv['capacity'] = self.capacity.to_dict()
        if self.latency:
            rv['latency'] = self.latency.to_dict()
        if self.attribute:
            rv['attribute'] = [ a.to_dict() for a in self.attribute ]
        return rv

class CPU(base):
    def __init__(self, type, attribute=[]):
        self.type = type
        self.attribute = [ self.init_class(Attribute, a) for a in \
                self.make_list(attribute) ]

    def to_dict(self):
        rv = { 'type': self.type}
        if self.attribute:
            rv['attribute'] = [ a.to_dict() for a in self.attribute ]
        return rv

class Storage(base):
    def __init__(self, amount, persistence, attribute=[]):
        if isinstance(amount, basestring):
            self.amount = float(amount)
        else:
            self.amount = amount
        self.presistence = persistence
        self.attribute = [ self.init_class(Attribute, a) \
                for a in self.make_list(attribute) ]

    def to_dict(self):
        rv = { 'amount': float(self.amount), 'persistence': self.persistence }
        if self.attribute:
            rv['attribute'] = [ a.to_dict() for a in self.attribute ]
        return rv

class OperatingSystem(base):
    def __init__(self, name, version=None, distribution=None,
            distributionversion=None, attribute=[]):
        self.name = name
        self.version = version
        self.distribution = distribution
        self.distributionversion = distributionversion
        self.attribute = [ self.init_class(Attribute, a) \
                for a in self.make_list(attribute) ]

    def to_dict(self):
        rv = { 'name': self.name }
        if self.version: rv['version'] = self.version
        if self.distribution: rv['version'] = self.distribution
        if self.distributionversion: rv['version'] = self.distributionversion
        if self.attribute:
            rv['attribute'] = [ a.to_dict() for a in self.attribute ]
        return rv

class Software(base):
    def __init__(self, location, install=None, attribute=[]):
        self.location = location
        self.install = install
        self.attribute = [ self.init_class(Attribute, a)\
                for a in self.make_list(attribute) ]

    def to_dict(self):
        rv = { 'location': self.location }
        if self.install: rv['install'] = self.install
        if self.attribute:
            rv['attribute'] = [ a.to_dict() for a in self.attribute ]
        return rv

class Interface(base):
    def __init__(self, substrate, capacity=None, latency=None, attribute=[],
            element=None):
        if isinstance(substrate, basestring):
            self.substrate = [ substrate ]
        else:
            self.substrate = substrate
        self.capacity = self.init_class(Capacity, capacity)
        self.latency = self.init_class(Latency, latency)
        self.attribute = [ self.init_class(Attribute, a) \
                for a in self.make_list(attribute) ]
        self.element = element 
        self.subs = [ ]

    def to_dict(self):
        rv = { 'substrate': self.substrate }
        if self.capacity:
            rv['capacity'] = self.capacity.to_dict()
        if self.latency:
            rv['latency'] = self.latency.to_dict()
        if self.attribute:
            rv['attribute'] = [ a.to_dict() for a in self.attribute ]
        return rv

class Computer(base):
    def __init__(self, cpu=[], os=[], software=[], storage=[], interface=[],
            attribute=[]):
        def assign_element(i):
            i.element = self

        self.cpu = [ self.init_class(CPU, c)  for c in self.make_list(cpu) ]
        self.os = [ self.init_class(OperatingSystem, c) \
                for c in self.make_list(os) ]
        self.software = [ self.init_class(Software, c) \
                for c in self.make_list(software) ]
        self.storage = [ self.init_class(Storage, c) \
                for c in self.make_list(storage) ]
        self.interface = [ self.init_class(Interface, c) \
                for c in self.make_list(interface) ]
        self.attribute = [ self.init_class(Attribute, a) \
                for a in self.make_list(attribute) ]
        map(assign_element, self.interface)

    def to_dict(self):
        rv = { }
        if self.cpu:
            rv['cpu'] = [ c.to_dict() for  c in self.cpu ]
        if self.os:
            rv['os'] = [ o.to_dict() for o in self.os ]
        if self.software:
            rv['software'] = [ s.to_dict() for s in self.software ]
        if self.storage:
            rv['storage'] = [ s.to_dict for s in self.storage ]
        if self.interface:
            rv['interface'] = [ i.to_dict() for i in self.interface ]
        if self.attribute:
            rv['attribute'] = [ i.to_dict() for i in self.attribute ]
        return rv

class Other(base):
    def __init__(self, interface=[], attribute=[]):
        self.interface = [ self.init_class(Interface, c) \
                for c in self.make_list(interface) ]
        self.attribute = [ self.init_class(Attribute, c) \
                for c in self.make_list(attribute) ]

    def to_dict(self):
        if self.interface:
            rv['interface'] = [ i.to_dict() for i in self.interface ]
        if self.attribute:
            rv['attribute'] = [ a.to_dict() for a in self.attribute ]


class Topology(base):
    @staticmethod
    def init_element(e):
        """
        e should be of the form { typename: args } where args is a dict full of
        the right parameters to initialize the element.  e should have only one
        key, but we walk e's keys in an arbitrary order and instantiate the
        first key we know how to.
        """
        classmap = {
                'computer': Computer,
                'other': Other,
            }

        for k in e.keys():
            cl = classmap.get(k, None)
            if cl: return cl(**e[k])

    def __init__(self, substrates=[], elements=[]):
        self.substrates = [ self.init_class(Substrate, s) \
                for s in self.make_list(substrates) ]
        self.elements = [ self.init_element(e) \
                for e in self.make_list(elements) ]
        # Could to this init in one gulp, but we want to look for duplicate
        # substrate names
        substrate_map = { }
        for s in self.substrates:
            if not substrate_map.has_key(s.name):
                substrate_map[s.name] = s
            else:
                raise ConsistencyError("Duplicate substrate name %s" % s.name)

        substrate_map = dict([ (s.name, s) for s in self.substrates ])
        for e in self.elements:
            for i in e.interface:
                for sn in i.substrate:
                    # NB, interfaces have substrate names in their substrate
                    # attribute.
                    if substrate_map.has_key(sn):
                        sub = substrate_map[sn]
                        i.subs.append(sub)
                        sub.interfaces.append(i)
                    else:
                        raise ConsistencyError("No such substrate for %s" % sn)

    def to_dict(self):
        rv = { }
        if self.substrates:
            rv['substrates'] = [ s.to_dict() for s in self.substrates ]
        if self.elements:
            rv['elements'] = [ s.to_dict() for s in self.elements ]
        return rv

def topology_from_xml(file=None, top="topology"):
    import xml.parsers.expat

    class parser:
        def __init__(self):
            self.stack = [ ]
            self.chars = ""
            self.key = ""
            self.have_chars = False
            self.current = { }
            self.in_cdata = False
        
        def start_element(self, name, attrs):
            self.chars = ""
            self.have_chars = False
            self.key = str(name)
            self.stack.append((self.current, self.key))
            self.current = { }

        def end_element(self, name):
            if self.have_chars:
                self.chars = self.chars.strip()
                if len(self.chars) >0:
                    addit = self.chars
                else:
                    addit = self.current
            else:
                addit = self.current

            parent, key = self.stack.pop()
            if parent.has_key(key):
                if isinstance(parent[key], list):
                    parent[key].append(addit)
                else:
                    parent[key] = [parent[key], addit]
            else:
                parent[key] = addit
            self.current = parent
            self.key = key

            self.chars = ""
            self.have_chars = False

        def char_data(self, data):
            self.have_chars = True
            self.chars += data

    p = parser()
    xp = xml.parsers.expat.ParserCreate()

    xp.StartElementHandler = p.start_element
    xp.EndElementHandler = p.end_element
    xp.CharacterDataHandler = p.char_data

    f = open(file, "r")

    xp.ParseFile(f)

    return Topology(**p.current[top])

def topology_to_xml(t, top=None):
    """
    Print the topology as XML.  This is quick and dirty, but should work for
    many purposes.  Convert the topology to a dict and print it recursively.
    """
    from xml.sax.saxutils import escape

    def dict_to_xml(e, top=None):
        if top: rv = "<%s>" % top
        else: rv = ""

        for k in e.keys():
            if isinstance(e[k], (basestring, int, float, long)):
                rv += "<%s>%s</%s>" % (k, escape(e[k]), k)
            elif isinstance(e[k], dict):
                rv += "<%s>%s</%s>" % (k, dict_to_xml(e[k]), k)
            elif getattr(e[k], '__iter__', None):
                for ee in e[k]:
                    if isinstance(ee, dict):
                        rv += "<%s>%s</%s>" % (k, dict_to_xml(ee), k)
                    else:
                        rv += "<%s>%s</%s>" % (k, escape(ee), k)
            else:
                raise ConsistencyError("What is this?? %s %s" % (k, e[k]))
        if top: rv += "</%s>" % top
        return rv

    return dict_to_xml(t.to_dict(), top)