CumulusNetworks-ifupdown2/ifupdown/iface.py

#!/usr/bin/python
#
# Copyright 2014 Cumulus Networks, Inc. All rights reserved.
# Author: Roopa Prabhu, roopa@cumulusnetworks.com
#
# iface --
#    interface object
#

"""ifupdown2 network interface object

It is modeled based on the 'iface' section in /etc/network/interfaces
file. But can be extended to include any other network interface format
"""

from collections import OrderedDict
import logging
import json

class ifaceType():
    UNKNOWN = 0x0
    IFACE = 0x1
    BRIDGE_VLAN = 0x2

class ifaceLinkType():
    UNKNOWN = 0x0
    LINK_SLAVE = 0x1
    LINK_MASTER = 0x2

class ifaceStatus():
    """Enumerates iface status """

    UNKNOWN = 0x1
    SUCCESS = 0x2
    ERROR = 0x3
    NOTFOUND = 0x4

    @classmethod
    def to_str(cls, state):
        if state == cls.UNKNOWN:
            return 'unknown'
        elif state == cls.SUCCESS:
            return 'success'
        elif state == cls.ERROR:
            return 'error'
        elif state == cls.NOTFOUND:
            return 'notfound'
    
    @classmethod
    def from_str(cls, state_str):
        if state_str == 'unknown':
            return cls.UNKNOWN
        elif state_str == 'success':
            return cls.SUCCESS
        elif state_str == 'error':
            return cls.ERROR

class ifaceState():
    """Enumerates iface state """

    UNKNOWN = 0x1
    NEW = 0x2
    PRE_UP = 0x3
    UP = 0x4
    POST_UP = 0x5
    PRE_DOWN = 0x6
    DOWN = 0x7
    POST_DOWN = 0x8

    # Pseudo states
    QUERY_CHECKCURR = 0x9
    QUERY_RUNNING = 0xa

    @classmethod
    def to_str(cls, state):
        if state == cls.UNKNOWN:
            return 'unknown'
        elif state == cls.NEW:
            return 'new'
        elif state == cls.PRE_UP:
            return 'pre-up'
        elif state == cls.UP:
            return 'up'
        elif state == cls.POST_UP:
            return 'post-up'
        elif state == cls.PRE_DOWN:
            return 'pre-down'
        elif state == cls.DOWN:
            return 'down'
        elif state == cls.POST_DOWN:
            return 'post-down'
        elif state == cls.QUERY_CHECKCURR:
            return 'query-checkcurr'
        elif state == cls.QUERY_RUNNING:
            return 'query-running'

    @classmethod
    def from_str(cls, state_str):
        if state_str == 'unknown':
            return cls.UNKNOWN
        elif state_str == 'new':
            return cls.NEW
        elif state_str == 'pre-up':
            return cls.PRE_UP
        elif state_str == 'up':
            return cls.UP
        elif state_str == 'post-up':
            return cls.POST_UP
        elif state_str == 'pre-down':
            return cls.PRE_DOWN
        elif state_str == 'down':
            return cls.DOWN
        elif state_str == 'post-down':
            return cls.POST_DOWN
        elif state_str == 'query-checkcurr':
            return cls.QUERY_CHECKCURR
        elif state_str == 'query-running':
            return cls.QUERY_RUNNING

class ifaceJsonEncoder(json.JSONEncoder):
    def default(self, o):
        retconfig = {}
        if o.config:
            retconfig = dict((k, (v[0] if len(v) == 1 else v))
                             for k,v in o.config.items())
        return OrderedDict({'name' : o.name,
                            'addr_method' : o.addr_method,
                            'addr_family' : o.addr_family,
                            'auto' : o.auto,
                            'config' : retconfig})

class ifaceJsonDecoder():
    @classmethod
    def json_to_ifaceobj(cls, ifaceattrdict):
        ifaceattrdict['config'] = OrderedDict([(k, (v if isinstance(v, list)
                                                else [v]))
                                for k,v in ifaceattrdict.get('config',
                                            OrderedDict()).items()])
        return iface(attrsdict=ifaceattrdict)

class iface():
    """ ifupdown2 iface object class
    
    Attributes:
        **name**      Name of the interface 

        **addr_family**     Address family eg, inet, inet6. Can be None to
                            indicate both address families

        **addr_method**     Address method eg, static, manual or None for
                            static address method

        **config**          dictionary of config lines for this interface

        **state**           Configuration state of an interface as defined by
                            ifaceState

        **status**          Configuration status of an interface as defined by
                            ifaceStatus

        **flags**           Internal flags used by iface processing

        **priv_flags**      private flags owned by module using this class

        **refcnt**          reference count, indicating number of interfaces
                            dependent on this iface

        **lowerifaces**     list of interface names lower to this interface or
                            this interface depends on

        **upperifaces**     list of interface names upper to this interface or
                            the interfaces that depend on this interface 

        **auto**            True if interface belongs to the auto class

        **classes**         List of classes the interface belongs to

        **env**             shell environment the interface needs during
                            execution

        **raw_config**      raw interface config from file
    """

    # flag to indicate that the object was created from pickled state
    _PICKLED = 0x1
    HAS_SIBLINGS = 0x2
    IFACERANGE_ENTRY = 0x3
    IFACERANGE_START = 0x4

    version = '0.1'

    def __init__(self, attrsdict={}):
        self._set_attrs_from_dict(attrsdict)
        self._config_status = {}
        """dict with config status of iface attributes"""
        self.state = ifaceState.NEW
        """iface state (of type ifaceState) """
        self.status = ifaceStatus.UNKNOWN
        """iface status (of type ifaceStatus) """
        self.status_str = None
        """iface status str (string representing the status) """
        self.flags = 0x0
        """iface flags """
        self.priv_flags = 0x0
        """iface priv flags. can be used by the external object manager """
        self.refcnt = 0
        """iface refcnt (incremented for each dependent this interface has) """
        self.lowerifaces = None 
        """lower iface list (in other words: slaves of this interface """
        self.upperifaces = None
        """upper iface list (in other words: master of this interface """
        self.classes = []
        """interface classes this iface belongs to """
        self.env = None
        """environment variable dict required for this interface to run"""
        self.raw_config = []
        """interface config/attributes in raw format (eg: as it appeared in the interfaces file)"""
        self.linkstate = None
        """linkstate of the interface"""
        self.type = ifaceType.UNKNOWN
        """interface type"""
        self.priv_data = None
        self.realname = None
        self.link_type = ifaceLinkType.UNKNOWN

    def _set_attrs_from_dict(self, attrdict):
        self.auto = attrdict.get('auto', False)
        self.name = attrdict.get('name')
        self.addr_family = attrdict.get('addr_family')
        self.addr_method = attrdict.get('addr_method')
        self.config = attrdict.get('config', OrderedDict())

    def inc_refcnt(self):
        """ increment refcnt of the interface. Usually used to indicate that
        it has dependents """
        self.refcnt += 1

    def dec_refcnt(self):
        """ decrement refcnt of the interface. Usually used to indicate that
        it has lost its dependent """
        self.refcnt -= 1

    def is_config_present(self):
        """ returns true if the interface has user provided config,
        false otherwise """
        addr_method = self.addr_method
        if addr_method and addr_method in ['dhcp', 'dhcp6', 'loopback']:
            return True
        if not self.config:
            return False
        else:
            return True

    def set_class(self, classname):
        """ appends class to the interfaces class list """
        self.classes.append(classname)

    def set_state_n_status(self, state, status):
        """ sets state and status of an interface """
        self.state = state
        self.status = status

    def set_flag(self, flag):
        self.flags |= flag

    def clear_flag(self, flag):
        self.flags &= ~flag

    def add_to_upperifaces(self, upperifacename):
        """ add to the list of upperifaces """
        if self.upperifaces:
            if upperifacename not in self.upperifaces:
                self.upperifaces.append(upperifacename)
        else:
            self.upperifaces = [upperifacename]

    def get_attr_value(self, attr_name):
        """ add to the list of upperifaces """
        return self.config.get(attr_name)
    
    def get_attr_value_first(self, attr_name):
        """ get first value of the specified attr name """
        attr_value_list = self.config.get(attr_name)
        if attr_value_list:
            return attr_value_list[0]
        return None

    def get_attrs_value_first(self, attrs):
        """ get first value of the first attr in the list.
            Useful when you have multiple attrs representing the
            same thing.
        """
        for attr in attrs:
            attr_value_list = self.config.get(attr)
            if attr_value_list:
                return attr_value_list[0]
        return None

    def get_attr_value_n(self, attr_name, attr_index):
        """ get n'th value of the specified attr name """
        attr_value_list = self.config.get(attr_name)
        if attr_value_list:
            try:
                return attr_value_list[attr_index]
            except:
                return None
        return None

    @property
    def get_env(self):
        """ get shell environment variables the interface must execute in """
        if not self.env:
            self.generate_env()
        return self.env

    def generate_env(self):
        """ generate shell environment variables dict interface must execute
        in. This is used to support legacy ifupdown scripts
        """
        env = {}
        config = self.config
        env['IFACE'] = self.name
        for attr, attr_value in config.items():
            attr_env_name = 'IF_%s' %attr.upper()
            env[attr_env_name] = attr_value[0]
        if env:
            self.env = env

    def update_config(self, attr_name, attr_value):
        """ add attribute name and value to the interface config """
        self.config.setdefault(attr_name, []).append(attr_value)

    def replace_config(self, attr_name, attr_value):
        """ add attribute name and value to the interface config """
        self.config[attr_name] = [attr_value]

    def delete_config(self, attr_name):
        """ add attribute name and value to the interface config """
        try:
            del self.config[attr_name]
        except:
            pass

    def update_config_dict(self, attrdict):
        self.config.update(attrdict)

    def update_config_with_status(self, attr_name, attr_value, attr_status=0):
        """ add attribute name and value to the interface config and also
        update the config_status dict with status of this attribute config """
        if not attr_value:
            attr_value = ''
        self.config.setdefault(attr_name, []).append(attr_value)
        self._config_status.setdefault(attr_name, []).append(attr_status)
        # set global iface state
        if attr_status == 1:
            self.status = ifaceStatus.ERROR
        elif self.status != ifaceStatus.ERROR:
            # Not already error, mark success
            self.status = ifaceStatus.SUCCESS

    def check_n_update_config_with_status_many(self, attr_names,
                                               attr_status=0):
        # set multiple attribute status to zero
        # also updates status only if the attribute is present
        for attr_name in attr_names:
            if not self.get_attr_value_first(attr_name):
                return
            self.config.setdefault(attr_name, []).append('')
            self._config_status.setdefault(attr_name, []).append(attr_status)

    def get_config_attr_status(self, attr_name, idx=0):
        """ get status of a attribute config on this interface.
        
        Looks at the iface _config_status dict"""
        return self._config_status.get(attr_name, [])[idx]

    def compare(self, dstiface):
        """ compares iface object with iface object passed as argument

        Returns True if object self is same as dstiface and False otherwise """

        if self.name != dstiface.name: return False
        if self.type != dstiface.type: return False
        if self.addr_family != dstiface.addr_family: return False
        if self.addr_method != dstiface.addr_method: return False
        if self.auto != dstiface.auto: return False
        if self.classes != dstiface.classes: return False
        if any(True for k in self.config if k not in dstiface.config):
            return False
        if any(True for k,v in self.config.items()
                    if v != dstiface.config.get(k)): return False
        return True


    def __getstate__(self):
        odict = self.__dict__.copy()
        del odict['state']
        del odict['status']
        del odict['lowerifaces']
        del odict['upperifaces']
        del odict['refcnt']
        del odict['_config_status']
        del odict['flags']
        del odict['priv_flags']
        del odict['raw_config']
        del odict['linkstate']
        del odict['env']
        del odict['link_type']
        return odict

    def __setstate__(self, dict):
        self.__dict__.update(dict)
        self._config_status = {}
        self.state = ifaceState.NEW
        self.status = ifaceStatus.UNKNOWN
        self.refcnt = 0
        self.flags = 0
        self.lowerifaces = None
        self.upperifaces = None
        self.linkstate = None
        self.env = None
        self.priv_flags = 0
        self.raw_config = []
        self.flags |= self._PICKLED
        self.link_type = ifaceLinkType.UNKNOWN

    def dump_raw(self, logger):
        indent = '  '
        if self.auto:
            print 'auto %s' %self.name
        print (self.raw_config[0])
        for i in range(1, len(self.raw_config)):
            print(indent + self.raw_config[i])
        
    def dump(self, logger):
        indent = '\t'
        logger.info(self.name + ' : {')
        logger.info(indent + 'family: %s' %self.addr_family)
        logger.info(indent + 'method: %s' %self.addr_method)
        logger.info(indent + 'flags: %x' %self.flags)
        logger.info(indent + 'state: %s'
                %ifaceState.to_str(self.state))
        logger.info(indent + 'status: %s'
                %ifaceStatus.to_str(self.status))
        logger.info(indent + 'refcnt: %d' %self.refcnt)
        d = self.lowerifaces
        if d:
            logger.info(indent + 'lowerdevs: %s' %str(d))
        else:
            logger.info(indent + 'lowerdevs: None')

        logger.info(indent + 'config: ')
        config = self.config
        if config:
            logger.info(indent + indent + str(config))
        logger.info('}')

    def dump_pretty(self, with_status=False,
                    successstr='success', errorstr='error',
                    unknownstr='unknown', use_realname=False):
        indent = '\t'
        outbuf = ''
        if use_realname and self.realname:
            name = '%s' %self.realname
        else:
            name = '%s' %self.name
        if self.auto:
            outbuf += 'auto %s\n' %name
        ifaceline = ''
        if self.type == ifaceType.BRIDGE_VLAN:
            ifaceline += 'vlan %s' %name
        else:
            ifaceline += 'iface %s' %name
        if self.addr_family:
            ifaceline += ' %s' %self.addr_family
        if self.addr_method:
            ifaceline += ' %s' %self.addr_method
        if with_status:
            status_str = None
            if (self.status == ifaceStatus.ERROR or
                    self.status == ifaceStatus.NOTFOUND):
                if self.status_str:
                    ifaceline += ' (%s)' %self.status_str
                status_str = errorstr
            elif self.status == ifaceStatus.SUCCESS:
                status_str = successstr
            if status_str:
               outbuf += '{0:65} {1:>8}'.format(ifaceline, status_str) + '\n'
            else:
                outbuf += ifaceline + '\n'
            if self.status == ifaceStatus.NOTFOUND:
                outbuf = (outbuf.encode('utf8')
                    if isinstance(outbuf, unicode) else outbuf)
                print outbuf + '\n'
                return
        else:
            outbuf += ifaceline + '\n'
        config = self.config
        if config:
            for cname, cvaluelist in config.items():
                idx = 0
                for cv in cvaluelist:
                    if with_status:
                        s = self.get_config_attr_status(cname, idx)
                        if s == -1:
                            status_str = unknownstr
                        elif s == 1:
                            status_str = errorstr
                        elif s == 0:
                            status_str = successstr
                        outbuf += (indent + '{0:55} {1:>10}'.format(
                                   '%s %s' %(cname, cv), status_str)) + '\n'
                    else:
                        outbuf += indent + '%s %s\n' %(cname, cv)
                    idx += 1
        if with_status:
            outbuf = (outbuf.encode('utf8')
                        if isinstance(outbuf, unicode) else outbuf)
        print outbuf