--- a/Zeroconf.py Mon Aug 25 18:03:10 2008 +0200
+++ b/Zeroconf.py Tue Aug 26 13:47:21 2008 +0200
@@ -19,33 +19,33 @@
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
"""0.12 update - allow selection of binding interface
- typo fix - Thanks A. M. Kuchlingi- removed all use of word 'Rendezvous' - this is an API change"""+ typo fix - Thanks A. M. Kuchlingi + removed all use of word 'Rendezvous' - this is an API change""" """0.11 update - correction to comments for addListener method
support for new record types seen from OS X
- ignore unknown DNS record types- works alongside other processes using port 5353 (e.g. on Mac OS X)- tested against Mac OS X 10.3.2's mDNSResponder- corrections to removal of list entries for service browser"""+ ignore unknown DNS record types + works alongside other processes using port 5353 (e.g. on Mac OS X) + tested against Mac OS X 10.3.2's mDNSResponder + corrections to removal of list entries for service browser""" """0.10 update - Jonathon Paisley contributed these corrections:
always multicast replies, even when query is unicast
- correct a pointer encoding problem- can now write records in any order- traceback shown on failure- better TXT record parsing- server is now separate from name- can cancel a service browser+ correct a pointer encoding problem + can now write records in any order + traceback shown on failure + better TXT record parsing + server is now separate from name + can cancel a service browser - modified some unit tests to accommodate these changes"""+ modified some unit tests to accommodate these changes""" """0.09 update - remove all records on service unregistration
fix DOS security problem with readName"""
@@ -54,25 +54,25 @@
"""0.07 update - faster shutdown on engine
pointer encoding of outgoing names
- ServiceBrowser now works+ ServiceBrowser now works """0.06 update - small improvements with unit tests
added defined exception types
- fixed hostname/interface problem- fixed socket timeout problem- fixed addServiceListener() typo bug- using select() for socket reads- tested on Debian unstable with Python 2.2.2"""+ fixed hostname/interface problem + fixed socket timeout problem + fixed addServiceListener() typo bug + using select() for socket reads + tested on Debian unstable with Python 2.2.2""" """0.05 update - ensure case insensitivty on domain names
support for unicast DNS queries"""
"""0.04 update - added some unit tests
added __ne__ adjuncts where required
- ensure names end in '.local.'- timeout on receiving socket for clean shutdown"""+ ensure names end in '.local.' + timeout on receiving socket for clean shutdown""" __author__ = "Paul Scott-Murphy"
__email__ = "paul at scott dash murphy dot com"
@@ -101,7 +101,7 @@
_MDNS_ADDR = '224.0.0.251'
@@ -155,1402 +155,1405 @@
# Mapping constants to names
_CLASSES = { _CLASS_IN : "in",
_TYPES = { _TYPE_A : "a",
- """Current system time in milliseconds"""- return time.time() * 1000+ """Current system time in milliseconds""" + return time.time() * 1000 class NonLocalNameException(Exception):
class NonUniqueNameException(Exception):
class NamePartTooLongException(Exception):
class AbstractMethodException(Exception):
class BadTypeInNameException(Exception):
- def __init__(self, name, type, clazz):- self.key = string.lower(name)- self.clazz = clazz & _CLASS_MASK- self.unique = (clazz & _CLASS_UNIQUE) != 0+ def __init__(self, name, type, clazz): + self.key = string.lower(name) + self.clazz = clazz & _CLASS_MASK + self.unique = (clazz & _CLASS_UNIQUE) != 0 - def __eq__(self, other):- """Equality test on name, type, and class"""- if isinstance(other, DNSEntry):- return self.name == other.name and self.type == other.type and self.clazz == other.clazz+ def __eq__(self, other): + """Equality test on name, type, and class""" + if isinstance(other, DNSEntry): + return self.name == other.name and self.type == other.type and self.clazz == other.clazz - def __ne__(self, other):- """Non-equality test"""- return not self.__eq__(other)+ def __ne__(self, other): + """Non-equality test""" + return not self.__eq__(other) - def getClazz(self, clazz):- return "?(%s)" % (clazz)+ def getClazz(self, clazz): + return "?(%s)" % (clazz) - def getType(self, type):- return "?(%s)" % (type)+ def getType(self, type): + return "?(%s)" % (type) - def toString(self, hdr, other):- """String representation with additional information"""- result = "%s[%s,%s" % (hdr, self.getType(self.type), self.getClazz(self.clazz))- result += ",%s]" % (other)+ def toString(self, hdr, other): + """String representation with additional information""" + result = "%s[%s,%s" % (hdr, self.getType(self.type), self.getClazz(self.clazz)) + result += ",%s]" % (other) class DNSQuestion(DNSEntry):
- """A DNS question entry"""- def __init__(self, name, type, clazz):- if not name.endswith(".local."):- raise NonLocalNameException- DNSEntry.__init__(self, name, type, clazz)+ """A DNS question entry""" + def __init__(self, name, type, clazz): + if not name.endswith(".local."): + raise NonLocalNameException + DNSEntry.__init__(self, name, type, clazz) - def answeredBy(self, rec):- """Returns true if the question is answered by the record"""- return self.clazz == rec.clazz and (self.type == rec.type or self.type == _TYPE_ANY) and self.name == rec.name+ def answeredBy(self, rec): + """Returns true if the question is answered by the record""" + return self.clazz == rec.clazz and (self.type == rec.type or self.type == _TYPE_ANY) and self.name == rec.name
- """String representation"""- return DNSEntry.toString(self, "question", None)+ """String representation""" + return DNSEntry.toString(self, "question", None) class DNSRecord(DNSEntry):
- """A DNS record - like a DNS entry, but has a TTL"""- def __init__(self, name, type, clazz, ttl):- DNSEntry.__init__(self, name, type, clazz)- self.created = currentTimeMillis()+ """A DNS record - like a DNS entry, but has a TTL""" + def __init__(self, name, type, clazz, ttl): + DNSEntry.__init__(self, name, type, clazz) + self.created = currentTimeMillis() - def __eq__(self, other):- """Tests equality as per DNSRecord"""- if isinstance(other, DNSRecord):- return DNSEntry.__eq__(self, other)+ def __eq__(self, other): + """Tests equality as per DNSRecord""" + if isinstance(other, DNSRecord): + return DNSEntry.__eq__(self, other) - def suppressedBy(self, msg):- """Returns true if any answer in a message can suffice for the- information held in this record."""- for record in msg.answers:- if self.suppressedByAnswer(record):+ def suppressedBy(self, msg): + """Returns true if any answer in a message can suffice for the + information held in this record.""" + for record in msg.answers: + if self.suppressedByAnswer(record): - def suppressedByAnswer(self, other):- """Returns true if another record has same name, type and class,- and if its TTL is at least half of this record's."""- if self == other and other.ttl > (self.ttl / 2):+ def suppressedByAnswer(self, other): + """Returns true if another record has same name, type and class, + and if its TTL is at least half of this record's.""" + if self == other and other.ttl > (self.ttl / 2): - def getExpirationTime(self, percent):- """Returns the time at which this record will have expired- by a certain percentage."""- return self.created + (percent * self.ttl * 10)+ def getExpirationTime(self, percent): + """Returns the time at which this record will have expired + by a certain percentage.""" + return self.created + (percent * self.ttl * 10) - def getRemainingTTL(self, now):- """Returns the remaining TTL in seconds."""- return max(0, (self.getExpirationTime(100) - now) / 1000)+ def getRemainingTTL(self, now): + """Returns the remaining TTL in seconds.""" + return max(0, (self.getExpirationTime(100) - now) / 1000) - def isExpired(self, now):- """Returns true if this record has expired."""- return self.getExpirationTime(100) <= now+ def isExpired(self, now): + """Returns true if this record has expired.""" + return self.getExpirationTime(100) <= now - def isStale(self, now):- """Returns true if this record is at least half way expired."""- return self.getExpirationTime(50) <= now+ def isStale(self, now): + """Returns true if this record is at least half way expired.""" + return self.getExpirationTime(50) <= now - def resetTTL(self, other):- """Sets this record's TTL and created time to that of- self.created = other.created+ def resetTTL(self, other): + """Sets this record's TTL and created time to that of + self.created = other.created
- raise AbstractMethodException+ raise AbstractMethodException - def toString(self, other):- """String representation with addtional information"""- arg = "%s/%s,%s" % (self.ttl, self.getRemainingTTL(currentTimeMillis()), other)- return DNSEntry.toString(self, "record", arg)+ def toString(self, other): + """String representation with addtional information""" + arg = "%s/%s,%s" % (self.ttl, self.getRemainingTTL(currentTimeMillis()), other) + return DNSEntry.toString(self, "record", arg) class DNSAddress(DNSRecord):
- """A DNS address record"""- def __init__(self, name, type, clazz, ttl, address):- DNSRecord.__init__(self, name, type, clazz, ttl)+ """A DNS address record""" + def __init__(self, name, type, clazz, ttl, address): + DNSRecord.__init__(self, name, type, clazz, ttl)
- """Used in constructing an outgoing packet"""- out.writeString(self.address, len(self.address))+ """Used in constructing an outgoing packet""" + out.writeString(self.address, len(self.address)) - def __eq__(self, other):- """Tests equality on address"""- if isinstance(other, DNSAddress):- return self.address == other.address+ def __eq__(self, other): + """Tests equality on address""" + if isinstance(other, DNSAddress): + return self.address == other.address
- """String representation"""- return socket.inet_ntoa(self.address)+ """String representation""" + return socket.inet_ntoa(self.address) class DNSHinfo(DNSRecord):
- """A DNS host information record"""+ """A DNS host information record""" - def __init__(self, name, type, clazz, ttl, cpu, os):- DNSRecord.__init__(self, name, type, clazz, ttl)+ def __init__(self, name, type, clazz, ttl, cpu, os): + DNSRecord.__init__(self, name, type, clazz, ttl)
- """Used in constructing an outgoing packet"""- out.writeString(self.cpu, len(self.cpu))- out.writeString(self.os, len(self.os))+ """Used in constructing an outgoing packet""" + out.writeString(self.cpu, len(self.cpu)) + out.writeString(self.os, len(self.os)) - def __eq__(self, other):- """Tests equality on cpu and os"""- if isinstance(other, DNSHinfo):- return self.cpu == other.cpu and self.os == other.os+ def __eq__(self, other): + """Tests equality on cpu and os""" + if isinstance(other, DNSHinfo): + return self.cpu == other.cpu and self.os == other.os
- """String representation"""- return self.cpu + " " + self.os+ """String representation""" + return self.cpu + " " + self.os class DNSPointer(DNSRecord):
- """A DNS pointer record"""- def __init__(self, name, type, clazz, ttl, alias):- DNSRecord.__init__(self, name, type, clazz, ttl)+ """A DNS pointer record""" + def __init__(self, name, type, clazz, ttl, alias): + DNSRecord.__init__(self, name, type, clazz, ttl)
- """Used in constructing an outgoing packet"""- out.writeName(self.alias)+ """Used in constructing an outgoing packet""" + out.writeName(self.alias) - def __eq__(self, other):- """Tests equality on alias"""- if isinstance(other, DNSPointer):- return self.alias == other.alias+ def __eq__(self, other): + """Tests equality on alias""" + if isinstance(other, DNSPointer): + return self.alias == other.alias
- """String representation"""- return self.toString(self.alias)+ """String representation""" + return self.toString(self.alias) class DNSText(DNSRecord):
- """A DNS text record"""- def __init__(self, name, type, clazz, ttl, text):- DNSRecord.__init__(self, name, type, clazz, ttl)+ """A DNS text record""" + def __init__(self, name, type, clazz, ttl, text): + DNSRecord.__init__(self, name, type, clazz, ttl)
- """Used in constructing an outgoing packet"""- out.writeString(self.text, len(self.text))+ """Used in constructing an outgoing packet""" + out.writeString(self.text, len(self.text)) - def __eq__(self, other):- """Tests equality on text"""- if isinstance(other, DNSText):- return self.text == other.text+ def __eq__(self, other): + """Tests equality on text""" + if isinstance(other, DNSText): + return self.text == other.text
- """String representation"""- if len(self.text) > 10:- return self.toString(self.text[:7] + "...")- return self.toString(self.text)+ """String representation""" + if len(self.text) > 10: + return self.toString(self.text[:7] + "...") + return self.toString(self.text) class DNSService(DNSRecord):
- """A DNS service record"""- def __init__(self, name, type, clazz, ttl, priority, weight, port, server):- DNSRecord.__init__(self, name, type, clazz, ttl)- self.priority = priority+ """A DNS service record""" + def __init__(self, name, type, clazz, ttl, priority, weight, port, server): + DNSRecord.__init__(self, name, type, clazz, ttl) + self.priority = priority
- """Used in constructing an outgoing packet"""- out.writeShort(self.priority)- out.writeShort(self.weight)- out.writeShort(self.port)- out.writeName(self.server)+ """Used in constructing an outgoing packet""" + out.writeShort(self.priority) + out.writeShort(self.weight) + out.writeShort(self.port) + out.writeName(self.server) - def __eq__(self, other):- """Tests equality on priority, weight, port and server"""- if isinstance(other, DNSService):- return self.priority == other.priority and self.weight == other.weight and self.port == other.port and self.server == other.server+ def __eq__(self, other): + """Tests equality on priority, weight, port and server""" + if isinstance(other, DNSService): + return self.priority == other.priority and self.weight == other.weight and self.port == other.port and self.server == other.server
- """String representation"""- return self.toString("%s:%s" % (self.server, self.port))+ """String representation""" + return self.toString("%s:%s" % (self.server, self.port)) class DNSIncoming(object):
- """Object representation of an incoming DNS packet"""- def __init__(self, data):- """Constructor from string holding bytes of packet"""- self.numAuthorities = 0- self.numAdditionals = 0+ """Object representation of an incoming DNS packet""" + def __init__(self, data): + """Constructor from string holding bytes of packet""" + self.numAuthorities = 0 + self.numAdditionals = 0
- """Reads header portion of packet"""- length = struct.calcsize(format)- info = struct.unpack(format, self.data[self.offset:self.offset+length])+ """Reads header portion of packet""" + length = struct.calcsize(format) + info = struct.unpack(format, self.data[self.offset:self.offset+length])
- self.numQuestions = info[2]- self.numAnswers = info[3]- self.numAuthorities = info[4]- self.numAdditionals = info[5]+ self.numQuestions = info[2] + self.numAnswers = info[3] + self.numAuthorities = info[4] + self.numAdditionals = info[5] - def readQuestions(self):- """Reads questions section of packet"""- length = struct.calcsize(format)- for i in range(0, self.numQuestions):- info = struct.unpack(format, self.data[self.offset:self.offset+length])- question = DNSQuestion(name, info[0], info[1])- self.questions.append(question)+ def readQuestions(self): + """Reads questions section of packet""" + length = struct.calcsize(format) + for i in range(0, self.numQuestions): + info = struct.unpack(format, self.data[self.offset:self.offset+length]) + question = DNSQuestion(name, info[0], info[1]) + self.questions.append(question)
- """Reads an integer from the packet"""- length = struct.calcsize(format)- info = struct.unpack(format, self.data[self.offset:self.offset+length])+ """Reads an integer from the packet""" + length = struct.calcsize(format) + info = struct.unpack(format, self.data[self.offset:self.offset+length]) - def readCharacterString(self):- """Reads a character string from the packet"""- length = ord(self.data[self.offset])- return self.readString(length)+ def readCharacterString(self): + """Reads a character string from the packet""" + length = ord(self.data[self.offset]) + return self.readString(length) - def readString(self, len):- """Reads a string of a given length from the packet"""- format = '!' + str(len) + 's'- length = struct.calcsize(format)- info = struct.unpack(format, self.data[self.offset:self.offset+length])+ def readString(self, len): + """Reads a string of a given length from the packet""" + format = '!' + str(len) + 's' + length = struct.calcsize(format) + info = struct.unpack(format, self.data[self.offset:self.offset+length]) - def readUnsignedShort(self):- """Reads an unsigned short from the packet"""- length = struct.calcsize(format)- info = struct.unpack(format, self.data[self.offset:self.offset+length])+ def readUnsignedShort(self): + """Reads an unsigned short from the packet""" + length = struct.calcsize(format) + info = struct.unpack(format, self.data[self.offset:self.offset+length])
- """Reads the answers, authorities and additionals section of the packet"""- length = struct.calcsize(format)- n = self.numAnswers + self.numAuthorities + self.numAdditionals- domain = self.readName()- info = struct.unpack(format, self.data[self.offset:self.offset+length])+ """Reads the answers, authorities and additionals section of the packet""" + length = struct.calcsize(format) + n = self.numAnswers + self.numAuthorities + self.numAdditionals + domain = self.readName() + info = struct.unpack(format, self.data[self.offset:self.offset+length])
- rec = DNSAddress(domain, info[0], info[1], info[2], self.readString(4))- elif info[0] == _TYPE_CNAME or info[0] == _TYPE_PTR:- rec = DNSPointer(domain, info[0], info[1], info[2], self.readName())- elif info[0] == _TYPE_TXT:- rec = DNSText(domain, info[0], info[1], info[2], self.readString(info[3]))- elif info[0] == _TYPE_SRV:- rec = DNSService(domain, info[0], info[1], info[2], self.readUnsignedShort(), self.readUnsignedShort(), self.readUnsignedShort(), self.readName())- elif info[0] == _TYPE_HINFO:- rec = DNSHinfo(domain, info[0], info[1], info[2], self.readCharacterString(), self.readCharacterString())- elif info[0] == _TYPE_AAAA:- rec = DNSAddress(domain, info[0], info[1], info[2], self.readString(16))- # Try to ignore types we don't know about- # this may mean the rest of the name is- # unable to be parsed, and may show errors- # so this is left for debugging. New types- # encountered need to be parsed properly.- #print "UNKNOWN TYPE = " + str(info[0])- #raise BadTypeInNameException+ rec = DNSAddress(domain, info[0], info[1], info[2], self.readString(4)) + elif info[0] == _TYPE_CNAME or info[0] == _TYPE_PTR: + rec = DNSPointer(domain, info[0], info[1], info[2], self.readName()) + elif info[0] == _TYPE_TXT: + rec = DNSText(domain, info[0], info[1], info[2], self.readString(info[3])) + elif info[0] == _TYPE_SRV: + rec = DNSService(domain, info[0], info[1], info[2], self.readUnsignedShort(), self.readUnsignedShort(), self.readUnsignedShort(), self.readName()) + elif info[0] == _TYPE_HINFO: + rec = DNSHinfo(domain, info[0], info[1], info[2], self.readCharacterString(), self.readCharacterString()) + elif info[0] == _TYPE_AAAA: + rec = DNSAddress(domain, info[0], info[1], info[2], self.readString(16)) + # Try to ignore types we don't know about + # this may mean the rest of the name is + # unable to be parsed, and may show errors + # so this is left for debugging. New types + # encountered need to be parsed properly. + #print "UNKNOWN TYPE = " + str(info[0]) + #raise BadTypeInNameException
- self.answers.append(rec)- """Returns true if this is a query"""- return (self.flags & _FLAGS_QR_MASK) == _FLAGS_QR_QUERY+ self.answers.append(rec) + """Returns true if this is a query""" + return (self.flags & _FLAGS_QR_MASK) == _FLAGS_QR_QUERY
- """Returns true if this is a response"""- return (self.flags & _FLAGS_QR_MASK) == _FLAGS_QR_RESPONSE+ """Returns true if this is a response""" + return (self.flags & _FLAGS_QR_MASK) == _FLAGS_QR_RESPONSE - def readUTF(self, offset, len):- """Reads a UTF-8 string of a given length from the packet"""- result = self.data[offset:offset+len].decode('utf-8')- """Reads a domain name from the packet"""+ def readUTF(self, offset, len): + """Reads a UTF-8 string of a given length from the packet""" + result = self.data[offset:offset+len].decode('utf-8') + """Reads a domain name from the packet"""
- len = ord(self.data[off])- result = ''.join((result, self.readUTF(off, len) + '.'))- off = ((len & 0x3F) << 8) | ord(self.data[off])- raise "Bad domain name (circular) at " + str(off)- raise "Bad domain name at " + str(off)+ len = ord(self.data[off]) + result = ''.join((result, self.readUTF(off, len) + '.')) + off = ((len & 0x3F) << 8) | ord(self.data[off]) + raise "Bad domain name (circular) at " + str(off) + raise "Bad domain name at " + str(off)
class DNSOutgoing(object):
- """Object representation of an outgoing packet"""- def __init__(self, flags, multicast = 1):- self.multicast = multicast+ """Object representation of an outgoing packet""" + def __init__(self, flags, multicast = 1): + self.multicast = multicast - def addQuestion(self, record):- self.questions.append(record)+ def addQuestion(self, record): + self.questions.append(record) - def addAnswer(self, inp, record):- if not record.suppressedBy(inp):- self.addAnswerAtTime(record, 0)+ def addAnswer(self, inp, record): + if not record.suppressedBy(inp): + self.addAnswerAtTime(record, 0) - def addAnswerAtTime(self, record, now):- """Adds an answer if if does not expire by a certain time"""- if now == 0 or not record.isExpired(now):- self.answers.append((record, now))+ def addAnswerAtTime(self, record, now): + """Adds an answer if if does not expire by a certain time""" + if now == 0 or not record.isExpired(now): + self.answers.append((record, now)) - def addAuthorativeAnswer(self, record):- """Adds an authoritative answer"""- self.authorities.append(record)+ def addAuthorativeAnswer(self, record): + """Adds an authoritative answer""" + self.authorities.append(record) - def addAdditionalAnswer(self, record):- """Adds an additional answer"""- self.additionals.append(record)+ def addAdditionalAnswer(self, record): + """Adds an additional answer""" + self.additionals.append(record) - def writeByte(self, value):- """Writes a single byte to the packet"""- self.data.append(struct.pack(format, chr(value)))+ def writeByte(self, value): + """Writes a single byte to the packet""" + self.data.append(struct.pack(format, chr(value))) - def insertShort(self, index, value):- """Inserts an unsigned short in a certain position in the packet"""- self.data.insert(index, struct.pack(format, value))- def writeShort(self, value):- """Writes an unsigned short to the packet"""- self.data.append(struct.pack(format, value))+ def insertShort(self, index, value): + """Inserts an unsigned short in a certain position in the packet""" + self.data.insert(index, struct.pack(format, value)) + def writeShort(self, value): + """Writes an unsigned short to the packet""" + self.data.append(struct.pack(format, value)) - def writeInt(self, value):- """Writes an unsigned integer to the packet"""- self.data.append(struct.pack(format, int(value)))+ def writeInt(self, value): + """Writes an unsigned integer to the packet""" + self.data.append(struct.pack(format, int(value))) - def writeString(self, value, length):- """Writes a string to the packet"""- format = '!' + str(length) + 's'- self.data.append(struct.pack(format, value))+ def writeString(self, value, length): + """Writes a string to the packet""" + format = '!' + str(length) + 's' + self.data.append(struct.pack(format, value))
- """Writes a UTF-8 string of a given length to the packet"""- utfstr = s.encode('utf-8')- raise NamePartTooLongException- self.writeString(utfstr, length)+ """Writes a UTF-8 string of a given length to the packet""" + utfstr = s.encode('utf-8') + raise NamePartTooLongException + self.writeString(utfstr, length) - def writeName(self, name):- """Writes a domain name to the packet"""+ def writeName(self, name): + """Writes a domain name to the packet"""
- # Find existing instance of this name in packet- index = self.names[name]- # No record of this name already, so write it- # out as normal, recording the location of the name- # for future pointers to it.- self.names[name] = self.size- parts = name.split('.')+ # Find existing instance of this name in packet + index = self.names[name] + # No record of this name already, so write it + # out as normal, recording the location of the name + # for future pointers to it. + self.names[name] = self.size + parts = name.split('.') - # An index was found, so write a pointer to it- self.writeByte((index >> 8) | 0xC0)+ # An index was found, so write a pointer to it + self.writeByte((index >> 8) | 0xC0) - def writeQuestion(self, question):- """Writes a question to the packet"""- self.writeName(question.name)- self.writeShort(question.type)- self.writeShort(question.clazz)+ def writeQuestion(self, question): + """Writes a question to the packet""" + self.writeName(question.name) + self.writeShort(question.type) + self.writeShort(question.clazz) - def writeRecord(self, record, now):- """Writes a record (answer, authoritative answer, additional) to- self.writeName(record.name)- self.writeShort(record.type)- if record.unique and self.multicast:- self.writeShort(record.clazz | _CLASS_UNIQUE)- self.writeShort(record.clazz)- self.writeInt(record.ttl)- self.writeInt(record.getRemainingTTL(now))- # Adjust size for the short we will write before this record- length = len(''.join(self.data[index:]))- self.insertShort(index, length) # Here is the short we adjusted for+ def writeRecord(self, record, now): + """Writes a record (answer, authoritative answer, additional) to + self.writeName(record.name) + self.writeShort(record.type) + if record.unique and self.multicast: + self.writeShort(record.clazz | _CLASS_UNIQUE) + self.writeShort(record.clazz) + self.writeInt(record.ttl) + self.writeInt(record.getRemainingTTL(now)) + # Adjust size for the short we will write before this record + length = len(''.join(self.data[index:])) + self.insertShort(index, length) # Here is the short we adjusted for
- """Returns a string containing the packet's bytes+ """Returns a string containing the packet's bytes - No further parts should be added to the packet once this- for question in self.questions:- self.writeQuestion(question)- for answer, time in self.answers:- self.writeRecord(answer, time)- for authority in self.authorities:- self.writeRecord(authority, 0)- for additional in self.additionals:- self.writeRecord(additional, 0)- self.insertShort(0, len(self.additionals))- self.insertShort(0, len(self.authorities))- self.insertShort(0, len(self.answers))- self.insertShort(0, len(self.questions))- self.insertShort(0, self.flags)- self.insertShort(0, self.id)- return ''.join(self.data)+ No further parts should be added to the packet once this + for question in self.questions: + self.writeQuestion(question) + for answer, time in self.answers: + self.writeRecord(answer, time) + for authority in self.authorities: + self.writeRecord(authority, 0) + for additional in self.additionals: + self.writeRecord(additional, 0) + self.insertShort(0, len(self.additionals)) + self.insertShort(0, len(self.authorities)) + self.insertShort(0, len(self.answers)) + self.insertShort(0, len(self.questions)) + self.insertShort(0, self.flags) + self.insertShort(0, self.id) + return ''.join(self.data) - """A cache of DNS entries"""+ """A cache of DNS entries"""
- list = self.cache[entry.key]- list = self.cache[entry.key] = []+ list = self.cache[entry.key] + list = self.cache[entry.key] = [] - def remove(self, entry):- list = self.cache[entry.key]+ def remove(self, entry): + list = self.cache[entry.key]
- """Gets an entry by key. Will return None if there is no- list = self.cache[entry.key]- return list[list.index(entry)]+ """Gets an entry by key. Will return None if there is no + list = self.cache[entry.key] + return list[list.index(entry)] - def getByDetails(self, name, type, clazz):- """Gets an entry by details. Will return None if there is- entry = DNSEntry(name, type, clazz)+ def getByDetails(self, name, type, clazz): + """Gets an entry by details. Will return None if there is + entry = DNSEntry(name, type, clazz) - def entriesWithName(self, name):- """Returns a list of entries whose key matches the name."""- return self.cache[name]+ def entriesWithName(self, name): + """Returns a list of entries whose key matches the name.""" + return self.cache[name]
- """Returns a list of all entries"""- def add(x, y): return x+y- return reduce(add, self.cache.values())+ """Returns a list of all entries""" + def add(x, y): return x+y + return reduce(add, self.cache.values()) class Engine(threading.Thread):
- """An engine wraps read access to sockets, allowing objects that- need to receive data from sockets to be called back when the+ """An engine wraps read access to sockets, allowing objects that + need to receive data from sockets to be called back when the - A reader needs a handle_read() method, which is called when the socket- it is interested in is ready for reading.+ A reader needs a handle_read() method, which is called when the socket + it is interested in is ready for reading. - Writers are not implemented here, because we only send short+ Writers are not implemented here, because we only send short - def __init__(self, zeroconf):- threading.Thread.__init__(self)- self.zeroconf = zeroconf- self.readers = {} # maps socket to reader- self.condition = threading.Condition()+ def __init__(self, zeroconf): + threading.Thread.__init__(self) + self.zeroconf = zeroconf + self.readers = {} # maps socket to reader + self.condition = threading.Condition()
- while not globals()['_GLOBAL_DONE']:- # No sockets to manage, but we wait for the timeout- # or addition of a socket- self.condition.acquire()- self.condition.wait(self.timeout)- self.condition.release()- rr, wr, er = select.select(rs, [], [], self.timeout)- self.readers[socket].handle_read()+ while not globals()['_GLOBAL_DONE']: + # No sockets to manage, but we wait for the timeout + # or addition of a socket + self.condition.acquire() + self.condition.wait(self.timeout) + self.condition.release() + rr, wr, er = select.select(rs, [], [], self.timeout) + self.readers[socket].handle_read()
- self.condition.acquire()- result = self.readers.keys()- self.condition.release()- def addReader(self, reader, socket):- self.condition.acquire()- self.readers[socket] = reader- self.condition.notify()- self.condition.release()+ self.condition.acquire() + result = self.readers.keys() + self.condition.release() + def addReader(self, reader, socket): + self.condition.acquire() + self.readers[socket] = reader + self.condition.notify() + self.condition.release() - def delReader(self, socket):- self.condition.acquire()- del(self.readers[socket])- self.condition.notify()- self.condition.release()+ def delReader(self, socket): + self.condition.acquire() + del(self.readers[socket]) + self.condition.notify() + self.condition.release()
- self.condition.acquire()- self.condition.notify()- self.condition.release()+ self.condition.acquire() + self.condition.notify() + self.condition.release() - """A Listener is used by this module to listen on the multicast- group to which DNS messages are sent, allowing the implementation- to cache information as it arrives.+ """A Listener is used by this module to listen on the multicast + group to which DNS messages are sent, allowing the implementation + to cache information as it arrives. - It requires registration with an Engine object in order to have- the read() method called when a socket is availble for reading."""- def __init__(self, zeroconf):- self.zeroconf = zeroconf- self.zeroconf.engine.addReader(self, self.zeroconf.socket)+ It requires registration with an Engine object in order to have + the read() method called when a socket is availble for reading.""" + def __init__(self, zeroconf): + self.zeroconf = zeroconf + self.zeroconf.engine.addReader(self, self.zeroconf.socket)
- data, (addr, port) = self.zeroconf.socket.recvfrom(_MAX_MSG_ABSOLUTE)- msg = DNSIncoming(data)- # Always multicast responses- self.zeroconf.handleQuery(msg, _MDNS_ADDR, _MDNS_PORT)- # If it's not a multicast query, reply via unicast- elif port == _DNS_PORT:- self.zeroconf.handleQuery(msg, addr, port)- self.zeroconf.handleQuery(msg, _MDNS_ADDR, _MDNS_PORT)- self.zeroconf.handleResponse(msg)+ data, (addr, port) = self.zeroconf.socket.recvfrom(_MAX_MSG_ABSOLUTE) + msg = DNSIncoming(data) + # Always multicast responses + self.zeroconf.handleQuery(msg, _MDNS_ADDR, _MDNS_PORT) + # If it's not a multicast query, reply via unicast + elif port == _DNS_PORT: + self.zeroconf.handleQuery(msg, addr, port) + self.zeroconf.handleQuery(msg, _MDNS_ADDR, _MDNS_PORT) + self.zeroconf.handleResponse(msg) class Reaper(threading.Thread):
- """A Reaper is used by this module to remove cache entries that- def __init__(self, zeroconf):- threading.Thread.__init__(self)- self.zeroconf = zeroconf+ """A Reaper is used by this module to remove cache entries that + def __init__(self, zeroconf): + threading.Thread.__init__(self) + self.zeroconf = zeroconf
- self.zeroconf.wait(10 * 1000)- if globals()['_GLOBAL_DONE']:- now = currentTimeMillis()- for record in self.zeroconf.cache.entries():- if record.isExpired(now):- self.zeroconf.updateRecord(now, record)- self.zeroconf.cache.remove(record)+ self.zeroconf.wait(10 * 1000) + if globals()['_GLOBAL_DONE']: + now = currentTimeMillis() + for record in self.zeroconf.cache.entries(): + if record.isExpired(now): + self.zeroconf.updateRecord(now, record) + self.zeroconf.cache.remove(record) class ServiceBrowser(threading.Thread):
- """Used to browse for a service of a specific type.+ """Used to browse for a service of a specific type. - The listener object will have its addService() and- removeService() methods called when this browser- discovers changes in the services availability."""- def __init__(self, zeroconf, type, listener):- """Creates a browser for a specific type"""- threading.Thread.__init__(self)- self.zeroconf = zeroconf- self.listener = listener- self.nextTime = currentTimeMillis()- self.delay = _BROWSER_TIME+ The listener object will have its addService() and + removeService() methods called when this browser + discovers changes in the services availability.""" + def __init__(self, zeroconf, type, listener): + """Creates a browser for a specific type""" + threading.Thread.__init__(self) + self.zeroconf = zeroconf + self.listener = listener + self.nextTime = currentTimeMillis() + self.delay = _BROWSER_TIME - self.zeroconf.addListener(self, DNSQuestion(self.type, _TYPE_PTR, _CLASS_IN))+ self.zeroconf.addListener(self, DNSQuestion(self.type, _TYPE_PTR, _CLASS_IN)) - def updateRecord(self, zeroconf, now, record):- """Callback invoked by Zeroconf when new information arrives.+ def updateRecord(self, zeroconf, now, record): + """Callback invoked by Zeroconf when new information arrives. - Updates information required by browser in the Zeroconf cache."""- if record.type == _TYPE_PTR and record.name == self.type:- expired = record.isExpired(now)- oldrecord = self.services[record.alias.lower()]- oldrecord.resetTTL(record)- del(self.services[record.alias.lower()])- callback = lambda x: self.listener.removeService(x, self.type, record.alias)- self.list.append(callback)- self.services[record.alias.lower()] = record- callback = lambda x: self.listener.addService(x, self.type, record.alias)- self.list.append(callback)+ Updates information required by browser in the Zeroconf cache.""" + if record.type == _TYPE_PTR and record.name == self.type: + expired = record.isExpired(now) + oldrecord = self.services[record.alias.lower()] + oldrecord.resetTTL(record) + del(self.services[record.alias.lower()]) + callback = lambda x: self.listener.removeService(x, self.type, record.alias) + self.list.append(callback) + self.services[record.alias.lower()] = record + callback = lambda x: self.listener.addService(x, self.type, record.alias) + self.list.append(callback) - expires = record.getExpirationTime(75)- if expires < self.nextTime:- self.nextTime = expires+ expires = record.getExpirationTime(75) + if expires < self.nextTime: + self.nextTime = expires
- self.zeroconf.notifyAll()+ self.zeroconf.notifyAll()
- now = currentTimeMillis()- if len(self.list) == 0 and self.nextTime > now:- self.zeroconf.wait(self.nextTime - now)- if globals()['_GLOBAL_DONE'] or self.done:- now = currentTimeMillis()+ now = currentTimeMillis() + if len(self.list) == 0 and self.nextTime > now: + self.zeroconf.wait(self.nextTime - now) + if globals()['_GLOBAL_DONE'] or self.done: + now = currentTimeMillis() - if self.nextTime <= now:- out = DNSOutgoing(_FLAGS_QR_QUERY)- out.addQuestion(DNSQuestion(self.type, _TYPE_PTR, _CLASS_IN))- for record in self.services.values():- if not record.isExpired(now):- out.addAnswerAtTime(record, now)- self.zeroconf.send(out)- self.nextTime = now + self.delay- self.delay = min(20 * 1000, self.delay * 2)+ if self.nextTime <= now: + out = DNSOutgoing(_FLAGS_QR_QUERY) + out.addQuestion(DNSQuestion(self.type, _TYPE_PTR, _CLASS_IN)) + for record in self.services.values(): + if not record.isExpired(now): + out.addAnswerAtTime(record, now) + self.zeroconf.send(out) + self.nextTime = now + self.delay + self.delay = min(20 * 1000, self.delay * 2)
- event = self.list.pop(0)+ event = self.list.pop(0)
class ServiceInfo(object):
- """Service information"""- def __init__(self, type, name, address=None, port=None, weight=0, priority=0, properties=None, server=None):- """Create a service description.+ """Service information""" + def __init__(self, type, name, address=None, port=None, weight=0, priority=0, properties=None, server=None): + """Create a service description. - type: fully qualified service type name- name: fully qualified service name- address: IP address as unsigned short, network byte order- port: port that the service runs on- weight: weight of the service- priority: priority of the service- properties: dictionary of properties (or a string holding the bytes for the text field)- server: fully qualified name for service host (defaults to name)"""+ type: fully qualified service type name + name: fully qualified service name + address: IP address as unsigned short, network byte order + port: port that the service runs on + weight: weight of the service + priority: priority of the service + properties: dictionary of properties (or a string holding the bytes for the text field) + server: fully qualified name for service host (defaults to name)""" - if not name.endswith(type):- raise BadTypeInNameException- self.priority = priority- self.setProperties(properties)+ if not name.endswith(type): + raise BadTypeInNameException + self.priority = priority + self.setProperties(properties) - def setProperties(self, properties):- """Sets properties and text of this info from a dictionary"""- if isinstance(properties, dict):- self.properties = properties- value = properties[key]- suffix = ''.encode('utf-8')- elif isinstance(value, str):- suffix = value.encode('utf-8')- elif isinstance(value, int):- suffix = ''.encode('utf-8')- list.append('='.join((key, suffix)))- result = ''.join((result, struct.pack('!c', chr(len(item))), item))+ def setProperties(self, properties): + """Sets properties and text of this info from a dictionary""" + if isinstance(properties, dict): + self.properties = properties + value = properties[key] + suffix = ''.encode('utf-8') + elif isinstance(value, str): + suffix = value.encode('utf-8') + elif isinstance(value, int): + suffix = ''.encode('utf-8') + list.append('='.join((key, suffix))) + result = ''.join((result, struct.pack('!c', chr(len(item))), item)) - def setText(self, text):- """Sets properties and text given a text field"""- length = ord(text[index])- strs.append(text[index:index+length])- # No equals sign at all- elif value == 'false' or not value:+ def setText(self, text): + """Sets properties and text given a text field""" + length = ord(text[index]) + strs.append(text[index:index+length]) + # No equals sign at all + elif value == 'false' or not value: - # Only update non-existent properties- if key and result.get(key) == None:+ # Only update non-existent properties + if key and result.get(key) == None: - self.properties = result+ self.properties = result
- if self.type is not None and self.name.endswith("." + self.type):- return self.name[:len(self.name) - len(self.type) - 1]+ if self.type is not None and self.name.endswith("." + self.type): + return self.name[:len(self.name) - len(self.type) - 1]
- """Pirority accessor"""+ """Pirority accessor"""
- def getProperties(self):- """Properties accessor"""+ def getProperties(self): + """Properties accessor"""
- def updateRecord(self, zeroconf, now, record):- """Updates service information from a DNS record"""- if record is not None and not record.isExpired(now):- if record.type == _TYPE_A:- if record.name == self.name:- self.address = record.address- elif record.type == _TYPE_SRV:- if record.name == self.name:- self.server = record.server- self.port = record.port- self.weight = record.weight- self.priority = record.priority- self.updateRecord(zeroconf, now, zeroconf.cache.getByDetails(self.server, _TYPE_A, _CLASS_IN))- elif record.type == _TYPE_TXT:- if record.name == self.name:- self.setText(record.text)+ def updateRecord(self, zeroconf, now, record): + """Updates service information from a DNS record""" + if record is not None and not record.isExpired(now): + if record.type == _TYPE_A: + if record.name == self.name: + self.address = record.address + elif record.type == _TYPE_SRV: + if record.name == self.name: + self.server = record.server + self.port = record.port + self.weight = record.weight + self.priority = record.priority + self.updateRecord(zeroconf, now, zeroconf.cache.getByDetails(self.server, _TYPE_A, _CLASS_IN)) + elif record.type == _TYPE_TXT: + if record.name == self.name: + self.setText(record.text) - def request(self, zeroconf, timeout):- """Returns true if the service could be discovered on the- network, and updates this object with details discovered.- now = currentTimeMillis()- zeroconf.addListener(self, DNSQuestion(self.name, _TYPE_ANY, _CLASS_IN))- while self.server is None or self.address is None or self.text is None:- out = DNSOutgoing(_FLAGS_QR_QUERY)- out.addQuestion(DNSQuestion(self.name, _TYPE_SRV, _CLASS_IN))- out.addAnswerAtTime(zeroconf.cache.getByDetails(self.name, _TYPE_SRV, _CLASS_IN), now)- out.addQuestion(DNSQuestion(self.name, _TYPE_TXT, _CLASS_IN))- out.addAnswerAtTime(zeroconf.cache.getByDetails(self.name, _TYPE_TXT, _CLASS_IN), now)- if self.server is not None:- out.addQuestion(DNSQuestion(self.server, _TYPE_A, _CLASS_IN))- out.addAnswerAtTime(zeroconf.cache.getByDetails(self.server, _TYPE_A, _CLASS_IN), now)+ def request(self, zeroconf, timeout): + """Returns true if the service could be discovered on the + network, and updates this object with details discovered. + now = currentTimeMillis() + zeroconf.addListener(self, DNSQuestion(self.name, _TYPE_ANY, _CLASS_IN)) + while self.server is None or self.address is None or self.text is None: + out = DNSOutgoing(_FLAGS_QR_QUERY) + out.addQuestion(DNSQuestion(self.name, _TYPE_SRV, _CLASS_IN)) + out.addAnswerAtTime(zeroconf.cache.getByDetails(self.name, _TYPE_SRV, _CLASS_IN), now) + out.addQuestion(DNSQuestion(self.name, _TYPE_TXT, _CLASS_IN)) + out.addAnswerAtTime(zeroconf.cache.getByDetails(self.name, _TYPE_TXT, _CLASS_IN), now) + if self.server is not None: + out.addQuestion(DNSQuestion(self.server, _TYPE_A, _CLASS_IN)) + out.addAnswerAtTime(zeroconf.cache.getByDetails(self.server, _TYPE_A, _CLASS_IN), now) - zeroconf.wait(min(next, last) - now)- now = currentTimeMillis()- zeroconf.removeListener(self)+ zeroconf.wait(min(next, last) - now) + now = currentTimeMillis() + zeroconf.removeListener(self) - def __eq__(self, other):- """Tests equality of service name"""- if isinstance(other, ServiceInfo):- return other.name == self.name+ def __eq__(self, other): + """Tests equality of service name""" + if isinstance(other, ServiceInfo): + return other.name == self.name - def __ne__(self, other):- """Non-equality test"""- return not self.__eq__(other)+ def __ne__(self, other): + """Non-equality test""" + return not self.__eq__(other)
- """String representation"""- result = "service[%s,%s:%s," % (self.name, socket.inet_ntoa(self.getAddress()), self.port)- if len(self.text) < 20:- result += self.text[:17] + "..."+ """String representation""" + result = "service[%s,%s:%s," % (self.name, socket.inet_ntoa(self.getAddress()), self.port) + if len(self.text) < 20: + result += self.text[:17] + "..." - """Implementation of Zeroconf Multicast DNS Service Discovery+ """Implementation of Zeroconf Multicast DNS Service Discovery - Supports registration, unregistration, queries and browsing.- def __init__(self, bindaddress=None):- """Creates an instance of the Zeroconf class, establishing- multicast communications, listening and reaping threads."""- globals()['_GLOBAL_DONE'] = 0- if bindaddress is None:- self.intf = socket.gethostbyname(socket.gethostname())- self.intf = bindaddress- self.group = ('', _MDNS_PORT)- self.socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)- self.socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)- self.socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEPORT, 1)- # SO_REUSEADDR should be equivalent to SO_REUSEPORT for- # multicast UDP sockets (p 731, "TCP/IP Illustrated,- # Volume 2"), but some BSD-derived systems require- # SO_REUSEPORT to be specified explicity. Also, not all- # versions of Python have SO_REUSEPORT available. So- # if you're on a BSD-based system, and haven't upgraded- # to Python 2.3 yet, you may find this library doesn't- self.socket.setsockopt(socket.SOL_IP, socket.IP_MULTICAST_TTL, 255)- self.socket.setsockopt(socket.SOL_IP, socket.IP_MULTICAST_LOOP, 1)- self.socket.bind(self.group)- # Some versions of linux raise an exception even though- # the SO_REUSE* options have been set, so ignore it- self.socket.setsockopt(socket.SOL_IP, socket.IP_MULTICAST_IF, socket.inet_aton(self.intf) + socket.inet_aton('0.0.0.0'))- self.socket.setsockopt(socket.SOL_IP, socket.IP_ADD_MEMBERSHIP, socket.inet_aton(_MDNS_ADDR) + socket.inet_aton('0.0.0.0'))+ Supports registration, unregistration, queries and browsing. + def __init__(self, bindaddress=None): + """Creates an instance of the Zeroconf class, establishing + multicast communications, listening and reaping threads.""" + globals()['_GLOBAL_DONE'] = 0 + self.intf = bindaddress + self.group = ('', _MDNS_PORT) + self.socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) + self.socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) + self.socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEPORT, 1) + # SO_REUSEADDR should be equivalent to SO_REUSEPORT for + # multicast UDP sockets (p 731, "TCP/IP Illustrated, + # Volume 2"), but some BSD-derived systems require + # SO_REUSEPORT to be specified explicity. Also, not all + # versions of Python have SO_REUSEPORT available. So + # if you're on a BSD-based system, and haven't upgraded + # to Python 2.3 yet, you may find this library doesn't + self.socket.setsockopt(socket.SOL_IP, socket.IP_MULTICAST_TTL, 255) + self.socket.setsockopt(socket.SOL_IP, socket.IP_MULTICAST_LOOP, 1) + self.socket.bind(self.group) + # Some versions of linux raise an exception even though + # the SO_REUSE* options have been set, so ignore it
+ if self.intf is not None: + self.socket.setsockopt(socket.SOL_IP, socket.IP_MULTICAST_IF, socket.inet_aton(self.intf) + socket.inet_aton('0.0.0.0')) + self.socket.setsockopt(socket.SOL_IP, socket.IP_ADD_MEMBERSHIP, socket.inet_aton(_MDNS_ADDR) + socket.inet_aton('0.0.0.0')) - self.cache = DNSCache()- self.condition = threading.Condition()- self.engine = Engine(self)- self.listener = Listener(self)- self.reaper = Reaper(self)+ self.cache = DNSCache()
- return self.intf.startswith("127.0.0.1")+ self.condition = threading.Condition() + self.engine = Engine(self) + self.listener = Listener(self) + self.reaper = Reaper(self)
- return self.intf.startswith("169.254.")+ if self.intf is not None: + return self.intf.startswith("127.0.0.1") - def wait(self, timeout):- """Calling thread waits for a given number of milliseconds or- self.condition.acquire()- self.condition.wait(timeout/1000)- self.condition.release()+ if self.intf is not None: + return self.intf.startswith("169.254.")
- """Notifies all waiting threads"""- self.condition.acquire()- self.condition.notifyAll()- self.condition.release()+ def wait(self, timeout): + """Calling thread waits for a given number of milliseconds or + self.condition.acquire() + self.condition.wait(timeout/1000) + self.condition.release() - def getServiceInfo(self, type, name, timeout=3000):- """Returns network's service information for a particular- name and type, or None if no service matches by the timeout,- which defaults to 3 seconds."""- info = ServiceInfo(type, name)- if info.request(self, timeout):+ """Notifies all waiting threads""" + self.condition.acquire() + self.condition.notifyAll() + self.condition.release() - def addServiceListener(self, type, listener):- """Adds a listener for a particular service type. This object- will then have its updateRecord method called when information- arrives for that type."""- self.removeServiceListener(listener)- self.browsers.append(ServiceBrowser(self, type, listener))+ def getServiceInfo(self, type, name, timeout=3000): + """Returns network's service information for a particular + name and type, or None if no service matches by the timeout, + which defaults to 3 seconds.""" + info = ServiceInfo(type, name) + if info.request(self, timeout): - def removeServiceListener(self, listener):- """Removes a listener from the set that is currently listening."""- for browser in self.browsers:- if browser.listener == listener:+ def addServiceListener(self, type, listener): + """Adds a listener for a particular service type. This object + will then have its updateRecord method called when information + arrives for that type.""" + self.removeServiceListener(listener) + self.browsers.append(ServiceBrowser(self, type, listener)) + def removeServiceListener(self, listener): + """Removes a listener from the set that is currently listening.""" + for browser in self.browsers: + if browser.listener == listener: - def registerService(self, info, ttl=_DNS_TTL):- """Registers service information to the network with a default TTL- of 60 seconds. Zeroconf will then respond to requests for- information for that service. The name of the service may be- changed if needed to make it unique on the network."""- self.checkService(info)- self.services[info.name.lower()] = info- now = currentTimeMillis()- self.wait(nextTime - now)- now = currentTimeMillis()- out = DNSOutgoing(_FLAGS_QR_RESPONSE | _FLAGS_AA)- out.addAnswerAtTime(DNSPointer(info.type, _TYPE_PTR, _CLASS_IN, ttl, info.name), 0)- out.addAnswerAtTime(DNSService(info.name, _TYPE_SRV, _CLASS_IN, ttl, info.priority, info.weight, info.port, info.server), 0)- out.addAnswerAtTime(DNSText(info.name, _TYPE_TXT, _CLASS_IN, ttl, info.text), 0)- out.addAnswerAtTime(DNSAddress(info.server, _TYPE_A, _CLASS_IN, ttl, info.address), 0)- nextTime += _REGISTER_TIME+ def registerService(self, info, ttl=_DNS_TTL): + """Registers service information to the network with a default TTL + of 60 seconds. Zeroconf will then respond to requests for + information for that service. The name of the service may be + changed if needed to make it unique on the network.""" + self.checkService(info) + self.services[info.name.lower()] = info + now = currentTimeMillis() + self.wait(nextTime - now) + now = currentTimeMillis() + out = DNSOutgoing(_FLAGS_QR_RESPONSE | _FLAGS_AA) + out.addAnswerAtTime(DNSPointer(info.type, _TYPE_PTR, _CLASS_IN, ttl, info.name), 0) + out.addAnswerAtTime(DNSService(info.name, _TYPE_SRV, _CLASS_IN, ttl, info.priority, info.weight, info.port, info.server), 0) + out.addAnswerAtTime(DNSText(info.name, _TYPE_TXT, _CLASS_IN, ttl, info.text), 0) + out.addAnswerAtTime(DNSAddress(info.server, _TYPE_A, _CLASS_IN, ttl, info.address), 0) + nextTime += _REGISTER_TIME - def unregisterService(self, info):- """Unregister a service."""- del(self.services[info.name.lower()])- now = currentTimeMillis()- self.wait(nextTime - now)- now = currentTimeMillis()- out = DNSOutgoing(_FLAGS_QR_RESPONSE | _FLAGS_AA)- out.addAnswerAtTime(DNSPointer(info.type, _TYPE_PTR, _CLASS_IN, 0, info.name), 0)- out.addAnswerAtTime(DNSService(info.name, _TYPE_SRV, _CLASS_IN, 0, info.priority, info.weight, info.port, info.name), 0)- out.addAnswerAtTime(DNSText(info.name, _TYPE_TXT, _CLASS_IN, 0, info.text), 0)- out.addAnswerAtTime(DNSAddress(info.server, _TYPE_A, _CLASS_IN, 0, info.address), 0)- nextTime += _UNREGISTER_TIME+ def unregisterService(self, info): + """Unregister a service.""" + del(self.services[info.name.lower()]) + now = currentTimeMillis() + self.wait(nextTime - now) + now = currentTimeMillis() + out = DNSOutgoing(_FLAGS_QR_RESPONSE | _FLAGS_AA) + out.addAnswerAtTime(DNSPointer(info.type, _TYPE_PTR, _CLASS_IN, 0, info.name), 0) + out.addAnswerAtTime(DNSService(info.name, _TYPE_SRV, _CLASS_IN, 0, info.priority, info.weight, info.port, info.name), 0) + out.addAnswerAtTime(DNSText(info.name, _TYPE_TXT, _CLASS_IN, 0, info.text), 0) + out.addAnswerAtTime(DNSAddress(info.server, _TYPE_A, _CLASS_IN, 0, info.address), 0) + nextTime += _UNREGISTER_TIME - def unregisterAllServices(self):- """Unregister all registered services."""- if len(self.services) > 0:- now = currentTimeMillis()- self.wait(nextTime - now)- now = currentTimeMillis()- out = DNSOutgoing(_FLAGS_QR_RESPONSE | _FLAGS_AA)- for info in self.services.values():- out.addAnswerAtTime(DNSPointer(info.type, _TYPE_PTR, _CLASS_IN, 0, info.name), 0)- out.addAnswerAtTime(DNSService(info.name, _TYPE_SRV, _CLASS_IN, 0, info.priority, info.weight, info.port, info.server), 0)- out.addAnswerAtTime(DNSText(info.name, _TYPE_TXT, _CLASS_IN, 0, info.text), 0)- out.addAnswerAtTime(DNSAddress(info.server, _TYPE_A, _CLASS_IN, 0, info.address), 0)- nextTime += _UNREGISTER_TIME+ def unregisterAllServices(self): + """Unregister all registered services.""" + if len(self.services) > 0: + now = currentTimeMillis() + self.wait(nextTime - now) + now = currentTimeMillis() + out = DNSOutgoing(_FLAGS_QR_RESPONSE | _FLAGS_AA) + for info in self.services.values(): + out.addAnswerAtTime(DNSPointer(info.type, _TYPE_PTR, _CLASS_IN, 0, info.name), 0) + out.addAnswerAtTime(DNSService(info.name, _TYPE_SRV, _CLASS_IN, 0, info.priority, info.weight, info.port, info.server), 0) + out.addAnswerAtTime(DNSText(info.name, _TYPE_TXT, _CLASS_IN, 0, info.text), 0) + out.addAnswerAtTime(DNSAddress(info.server, _TYPE_A, _CLASS_IN, 0, info.address), 0) + nextTime += _UNREGISTER_TIME - def checkService(self, info):- """Checks the network for a unique service name, modifying the- ServiceInfo passed in if it is not unique."""- now = currentTimeMillis()- for record in self.cache.entriesWithName(info.type):- if record.type == _TYPE_PTR and not record.isExpired(now) and record.alias == info.name:- if (info.name.find('.') < 0):- info.name = info.name + ".[" + info.address + ":" + info.port + "]." + info.type- self.checkService(info)- raise NonUniqueNameException- self.wait(nextTime - now)- now = currentTimeMillis()- out = DNSOutgoing(_FLAGS_QR_QUERY | _FLAGS_AA)- out.addQuestion(DNSQuestion(info.type, _TYPE_PTR, _CLASS_IN))- out.addAuthorativeAnswer(DNSPointer(info.type, _TYPE_PTR, _CLASS_IN, _DNS_TTL, info.name))- nextTime += _CHECK_TIME+ def checkService(self, info): + """Checks the network for a unique service name, modifying the + ServiceInfo passed in if it is not unique.""" + now = currentTimeMillis() + for record in self.cache.entriesWithName(info.type): + if record.type == _TYPE_PTR and not record.isExpired(now) and record.alias == info.name: + if (info.name.find('.') < 0): + info.name = info.name + ".[" + info.address + ":" + info.port + "]." + info.type + self.checkService(info) + raise NonUniqueNameException + self.wait(nextTime - now) + now = currentTimeMillis() + out = DNSOutgoing(_FLAGS_QR_QUERY | _FLAGS_AA) + out.addQuestion(DNSQuestion(info.type, _TYPE_PTR, _CLASS_IN)) + out.addAuthorativeAnswer(DNSPointer(info.type, _TYPE_PTR, _CLASS_IN, _DNS_TTL, info.name)) + nextTime += _CHECK_TIME - def addListener(self, listener, question):- """Adds a listener for a given question. The listener will have- its updateRecord method called when information is available to- answer the question."""- now = currentTimeMillis()- self.listeners.append(listener)- if question is not None:- for record in self.cache.entriesWithName(question.name):- if question.answeredBy(record) and not record.isExpired(now):- listener.updateRecord(self, now, record)+ def addListener(self, listener, question): + """Adds a listener for a given question. The listener will have + its updateRecord method called when information is available to + answer the question.""" + now = currentTimeMillis() + self.listeners.append(listener) + if question is not None: + for record in self.cache.entriesWithName(question.name): + if question.answeredBy(record) and not record.isExpired(now): + listener.updateRecord(self, now, record) - def removeListener(self, listener):- """Removes a listener."""- self.listeners.remove(listener)+ def removeListener(self, listener): + """Removes a listener.""" + self.listeners.remove(listener) - def updateRecord(self, now, rec):- """Used to notify listeners of new information that has updated- for listener in self.listeners:- listener.updateRecord(self, now, rec)+ def updateRecord(self, now, rec): + """Used to notify listeners of new information that has updated + for listener in self.listeners: + listener.updateRecord(self, now, rec) - def handleResponse(self, msg):- """Deal with incoming response packets. All answers- are held in the cache, and listeners are notified."""- now = currentTimeMillis()- for record in msg.answers:- expired = record.isExpired(now)- if record in self.cache.entries():- self.cache.remove(record)- entry = self.cache.get(record)- self.updateRecord(now, record)+ def handleResponse(self, msg): + """Deal with incoming response packets. All answers + are held in the cache, and listeners are notified.""" + now = currentTimeMillis() + for record in msg.answers: + expired = record.isExpired(now) + if record in self.cache.entries(): + self.cache.remove(record) + entry = self.cache.get(record) + self.updateRecord(now, record) - def handleQuery(self, msg, addr, port):- """Deal with incoming query packets. Provides a response if+ def handleQuery(self, msg, addr, port): + """Deal with incoming query packets. Provides a response if - # Support unicast client responses- out = DNSOutgoing(_FLAGS_QR_RESPONSE | _FLAGS_AA, 0)- for question in msg.questions:- out.addQuestion(question)- for question in msg.questions:- if question.type == _TYPE_PTR:- for service in self.services.values():- if question.name == service.type:- out = DNSOutgoing(_FLAGS_QR_RESPONSE | _FLAGS_AA)- out.addAnswer(msg, DNSPointer(service.type, _TYPE_PTR, _CLASS_IN, _DNS_TTL, service.name))- out = DNSOutgoing(_FLAGS_QR_RESPONSE | _FLAGS_AA)- # Answer A record queries for any service addresses we know- if question.type == _TYPE_A or question.type == _TYPE_ANY:- for service in self.services.values():- if service.server == question.name.lower():- out.addAnswer(msg, DNSAddress(question.name, _TYPE_A, _CLASS_IN | _CLASS_UNIQUE, _DNS_TTL, service.address))- service = self.services.get(question.name.lower(), None)- if not service: continue- if question.type == _TYPE_SRV or question.type == _TYPE_ANY:- out.addAnswer(msg, DNSService(question.name, _TYPE_SRV, _CLASS_IN | _CLASS_UNIQUE, _DNS_TTL, service.priority, service.weight, service.port, service.server))- if question.type == _TYPE_TXT or question.type == _TYPE_ANY:- out.addAnswer(msg, DNSText(question.name, _TYPE_TXT, _CLASS_IN | _CLASS_UNIQUE, _DNS_TTL, service.text))- if question.type == _TYPE_SRV:- out.addAdditionalAnswer(DNSAddress(service.server, _TYPE_A, _CLASS_IN | _CLASS_UNIQUE, _DNS_TTL, service.address))- if out is not None and out.answers:- self.send(out, addr, port)+ # Support unicast client responses + out = DNSOutgoing(_FLAGS_QR_RESPONSE | _FLAGS_AA, 0) + for question in msg.questions: + out.addQuestion(question) + for question in msg.questions: + if question.type == _TYPE_PTR: + for service in self.services.values(): + if question.name == service.type: + out = DNSOutgoing(_FLAGS_QR_RESPONSE | _FLAGS_AA) + out.addAnswer(msg, DNSPointer(service.type, _TYPE_PTR, _CLASS_IN, _DNS_TTL, service.name)) + out = DNSOutgoing(_FLAGS_QR_RESPONSE | _FLAGS_AA) + # Answer A record queries for any service addresses we know + if question.type == _TYPE_A or question.type == _TYPE_ANY: + for service in self.services.values(): + if service.server == question.name.lower(): + out.addAnswer(msg, DNSAddress(question.name, _TYPE_A, _CLASS_IN | _CLASS_UNIQUE, _DNS_TTL, service.address)) + service = self.services.get(question.name.lower(), None) + if not service: continue + if question.type == _TYPE_SRV or question.type == _TYPE_ANY: + out.addAnswer(msg, DNSService(question.name, _TYPE_SRV, _CLASS_IN | _CLASS_UNIQUE, _DNS_TTL, service.priority, service.weight, service.port, service.server)) + if question.type == _TYPE_TXT or question.type == _TYPE_ANY: + out.addAnswer(msg, DNSText(question.name, _TYPE_TXT, _CLASS_IN | _CLASS_UNIQUE, _DNS_TTL, service.text)) + if question.type == _TYPE_SRV: + out.addAdditionalAnswer(DNSAddress(service.server, _TYPE_A, _CLASS_IN | _CLASS_UNIQUE, _DNS_TTL, service.address)) + if out is not None and out.answers: + self.send(out, addr, port) - def send(self, out, addr = _MDNS_ADDR, port = _MDNS_PORT):- """Sends an outgoing packet."""- # This is a quick test to see if we can parse the packets we generate- #temp = DNSIncoming(out.packet())- bytes_sent = self.socket.sendto(out.packet(), 0, (addr, port))- # Ignore this, it may be a temporary loss of network connection+ def send(self, out, addr = _MDNS_ADDR, port = _MDNS_PORT): + """Sends an outgoing packet.""" + # This is a quick test to see if we can parse the packets we generate + #temp = DNSIncoming(out.packet()) + bytes_sent = self.socket.sendto(out.packet(), 0, (addr, port)) + # Ignore this, it may be a temporary loss of network connection
- """Ends the background threads, and prevent this instance from- servicing further queries."""- if globals()['_GLOBAL_DONE'] == 0:- globals()['_GLOBAL_DONE'] = 1- self.unregisterAllServices()- self.socket.setsockopt(socket.SOL_IP, socket.IP_DROP_MEMBERSHIP, socket.inet_aton(_MDNS_ADDR) + socket.inet_aton('0.0.0.0'))+ """Ends the background threads, and prevent this instance from + servicing further queries.""" + if globals()['_GLOBAL_DONE'] == 0: + globals()['_GLOBAL_DONE'] = 1 + self.unregisterAllServices() + self.socket.setsockopt(socket.SOL_IP, socket.IP_DROP_MEMBERSHIP, socket.inet_aton(_MDNS_ADDR) + socket.inet_aton('0.0.0.0')) # Test a few module features, including service registration, service
# query (for Zoe), and service unregistration.
-if __name__ == '__main__': - print "Multicast DNS Service Discovery for Python, version", __version__- print "1. Testing registration of a service..."- desc = {'version':'0.10','a':'test value', 'b':'another value'}- info = ServiceInfo("_http._tcp.local.", "My Service Name._http._tcp.local.", socket.inet_aton("127.0.0.1"), 1234, 0, 0, desc)- print " Registering service..."- r.registerService(info)- print " Registration done."- print "2. Testing query of service information..."- print " Getting ZOE service:", str(r.getServiceInfo("_http._tcp.local.", "ZOE._http._tcp.local."))- print "3. Testing query of own service..."- print " Getting self:", str(r.getServiceInfo("_http._tcp.local.", "My Service Name._http._tcp.local."))- print "4. Testing unregister of service information..."- r.unregisterService(info)- print " Unregister done."+if __name__ == '__main__': + print "Multicast DNS Service Discovery for Python, version", __version__ + print "1. Testing registration of a service..." + desc = {'version':'0.10','a':'test value', 'b':'another value'} + info = ServiceInfo("_http._tcp.local.", "My Service Name._http._tcp.local.", socket.inet_aton("127.0.0.1"), 1234, 0, 0, desc) + print " Registering service..." + r.registerService(info) + print " Registration done." + print "2. Testing query of service information..." + print " Getting ZOE service:", str(r.getServiceInfo("_http._tcp.local.", "ZOE._http._tcp.local.")) + print "3. Testing query of own service..." + print " Getting self:", str(r.getServiceInfo("_http._tcp.local.", "My Service Name._http._tcp.local.")) + print "4. Testing unregister of service information..." + r.unregisterService(info) + print " Unregister done." 