twisted.names.root.Resolver

class documentation

class Resolver(common.ResolverBase): (source)

Constructor: Resolver(hints, maximumQueries, reactor, resolverFactory)

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

Method	`__init__`	No summary
Instance Variable	`hints`	See `hints` parameter of `__init__`
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.
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	`_query`	Issue one query and return a `Deferred` which fires with its response.
Method	`_roots`	Return a list of two-tuples representing the addresses of the root servers, as defined by `self.hints`.
Instance Variable	`_maximumQueries`	See `maximumQueries` parameter of `__init__`
Instance Variable	`_reactor`	See `reactor` parameter of `__init__`
Instance Variable	`_resolverFactory`	See `resolverFactory` parameter of `__init__`

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	`getHostByName`	Resolve the domain name `name` into an IP address.
Method	`lookupAddress`	Perform an A record lookup.
Method	`lookupAddress6`	Perform an A6 record lookup.
Method	`lookupAFSDatabase`	Perform an AFSDB record lookup.
Method	`lookupAllRecords`	Perform an ALL_RECORD lookup.
Method	`lookupAuthority`	Perform an SOA record lookup.
Method	`lookupCanonicalName`	Perform a CNAME record lookup.
Method	`lookupHostInfo`	Perform a HINFO record lookup.
Method	`lookupIPV6Address`	Perform an AAAA record lookup.
Method	`lookupMailBox`	Perform an MB record lookup.
Method	`lookupMailboxInfo`	Perform an MINFO record lookup.
Method	`lookupMailExchange`	Perform an MX record lookup.
Method	`lookupMailGroup`	Perform an MG record lookup.
Method	`lookupMailRename`	Perform an MR record lookup.
Method	`lookupNameservers`	Perform an NS record lookup.
Method	`lookupNamingAuthorityPointer`	Perform a NAPTR record lookup.
Method	`lookupNull`	Perform a NULL record lookup.
Method	`lookupPointer`	Perform a PTR record lookup.
Method	`lookupResponsibility`	Perform an RP record lookup.
Method	`lookupSenderPolicy`	Perform a SPF record lookup.
Method	`lookupService`	Perform an SRV record lookup.
Method	`lookupText`	Perform a TXT record lookup.
Method	`lookupWellKnownServices`	Perform a WKS record lookup.
Method	`lookupZone`	Perform an AXFR record lookup.
Method	`query`	Dispatch `query` to the method which can handle its type.
Instance Variable	`typeToMethod`	Undocumented
Method	`_cbRecords`	Undocumented
Class Variable	`_errormap`	A `dict` mapping DNS protocol failure response codes to exception classes which will be used to represent those failures.
Class Variable	`_log`	Undocumented

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

overrides twisted.names.common.ResolverBase.__init__

Parameters
hints:`list` of `str`	A `list` of `str` giving the dotted quad representation of IP addresses of root servers at which to begin resolving names.
maximumQueries:`int`	An optional `int` giving the maximum number of queries which will be attempted to resolve a single name.
reactor:`IReactorTime` and `IReactorUDP` provider	An optional `IReactorTime` and `IReactorUDP` provider to use to bind UDP ports and manage timeouts.
resolverFactory:callable	An optional callable which accepts `reactor` and `servers` arguments and returns an instance that provides a `queryUDP` method. Defaults to `twisted.names.client.Resolver`.

hints = (source) ¶

See hints parameter of __init__

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

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

Parameters
query:`dns.Query`	The query to issue.
servers:`list` of `tuple` of `str` and `int`	The servers which might have an answer for this query.
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 `twisted.names.dns.RRHeader` 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:`Message`	The `Message` received in response to issuing `query`.
query:`dns.Query`.	The `dns.Query` which was issued.
timeout:`tuple` of `int`	The timeout to use if another query is indicated by this response.
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 `twisted.names.dns.RRHeader` giving the response to `query` or a `Deferred` which will fire with one of those.

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

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

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

def _roots(self): (source) ¶

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

_maximumQueries = (source) ¶

See maximumQueries parameter of __init__

_reactor = (source) ¶

See reactor parameter of __init__

_resolverFactory = (source) ¶

See resolverFactory parameter of __init__