twisted.names.root.Resolver : API documentation

Resolver implements recursive lookup starting from a specified list of root servers.

Instance Variables	hints	A `list` of `str` giving the dotted quad representation of IP addresses of root servers at which to begin resolving names.
	_maximumQueries	A `int` giving the maximum number of queries which will be attempted to resolve a single name.
	_reactor	A `IReactorTime` and `IReactorUDP` provider to use to bind UDP ports and manage timeouts.

Method	__init__	Undocumented
Method	discoveredAuthority	Undocumented
Method	_roots	Return a list of two-tuples representing the addresses of the root servers, as defined by `self.hints`.
Method	_query	Issue one query and return a `Deferred` which fires with its response.
Method	_lookup	Implement name lookup by recursively discovering the authoritative server for the name and then asking it, starting at one of the servers in `self.hints`.
Method	_discoverAuthority	Issue a query to a server and follow a delegation if necessary.
Method	_discoveredAuthority	Interpret the response to a query, checking for error codes and following delegations if necessary.

Inherited from ResolverBase:

Method	exceptionForCode	Convert a response code (one of the possible values of `dns.Message.rCode` to an exception instance representing it.
Method	query	Undocumented
Method	lookupAddress
Method	lookupIPV6Address
Method	lookupAddress6
Method	lookupMailExchange
Method	lookupNameservers
Method	lookupCanonicalName
Method	lookupMailBox
Method	lookupMailGroup
Method	lookupMailRename
Method	lookupPointer
Method	lookupAuthority
Method	lookupNull
Method	lookupWellKnownServices
Method	lookupService
Method	lookupHostInfo
Method	lookupMailboxInfo
Method	lookupText
Method	lookupResponsibility
Method	lookupAFSDatabase
Method	lookupZone
Method	lookupNamingAuthorityPointer
Method	lookupAllRecords
Method	getHostByName
Method	_cbRecords	Undocumented

def __init__(self, hints, maximumQueries=10, reactor=None): (source)

overrides twisted.names.common.ResolverBase.__init__

Undocumented

def _roots(self): (source)

Return a list of two-tuples representing the addresses of the root servers, as defined by self.hints.

def _query(self, query, servers, timeout, filter): (source)

Issue one query and return a Deferred which fires with its response.

Parameters	query	The query to issue. (type: `dns.Query` )
	servers	The servers which might have an answer for this query. (type: `list` of `tuple` of `str` and `int` )
	timeout	A timeout on how long to wait for the response. (type: `tuple` of `int` )
	filter	A flag indicating whether to filter the results. If `True`, the returned `Deferred` will fire with a three-tuple of lists of `RRHeaders` (like the return value of the lookup* methods of `IResolver`. IF `False`, the result will be a `Message` instance. (type: `bool` )
Returns	A `Deferred` which fires with the response or a timeout error. (type: `Deferred` )

def _lookup(self, name, cls, type, timeout): (source)

overrides twisted.names.common.ResolverBase._lookup

Implement name lookup by recursively discovering the authoritative server for the name and then asking it, starting at one of the servers in self.hints.

def _discoverAuthority(self, query, servers, timeout, queriesLeft): (source)

Issue a query to a server and follow a delegation if necessary.

Parameters	query	The query to issue. (type: `dns.Query` )
	servers	The servers which might have an answer for this query. (type: `list` of `tuple` of `str` and `int` )
	timeout	A `tuple` of `int` giving the timeout to use for this query.
	queriesLeft	A `int` giving the number of queries which may yet be attempted to answer this query before the attempt will be abandoned.
Returns	A `Deferred` which fires with a three-tuple of lists of `RRHeaders` giving the response, or with a `Failure` if there is a timeout or response error.

def _discoveredAuthority(self, response, query, timeout, queriesLeft): (source)

Interpret the response to a query, checking for error codes and following delegations if necessary.

Parameters	response	The `Message` received in response to issuing `query`. (type: `Message` )
	query	The `dns.Query` which was issued. (type: `dns.Query`. )
	timeout	The timeout to use if another query is indicated by this response. (type: `tuple` of `int` )
	queriesLeft	A `int` giving the number of queries which may yet be attempted to answer this query before the attempt will be abandoned.
Returns	A `Failure` indicating a response error, a three-tuple of lists of `RRHeaders` giving the response to `query` or a `Deferred` which will fire with one of those.

t.n.r.Resolver(common.ResolverBase) : class documentation