dns¶

DNS module.

exception wmflib.dns.DnsError[source]¶

Bases: wmflib.exceptions.WmflibError

Custom exception class for errors of the Dns class.

exception wmflib.dns.DnsNotFound[source]¶

Bases: wmflib.dns.DnsError

Custom exception class to indicate the record was not found.

One or more resource records exist for this domain but there isn’t a record matching the resource record type.

class wmflib.dns.Dns(*, nameserver_addresses: Optional[Sequence] = None, port: Optional[int] = None)[source]¶

Bases: object

Class to interact with the DNS.

Initialize the instance.

Parameters

nameserver_addresses (Sequence, optional) – the nameserveres address to use, if not set uses the OS configuration.
port (int, optional) – the port the nameserver_addresses nameserveres is listening to, if different from the default 53. This applies only if a nameserveres is explicitelyes specified.

resolve_ipv4(name: str) → List[str][source]¶

Perform a DNS lookup for an A record for the given name.

Parameters: name (str) – the name to resolve.
Returns: the list of IPv4 addresses as strings returned by the DNS response.
Return type: list

resolve_ipv6(name: str) → List[str][source]¶

Perform a DNS lookup for an AAAA record for the given name.

Parameters: name (str) – the name to resolve.
Returns: the list of IPv6 addresses as strings returned by the DNS response.
Return type: list

resolve_ips(name: str) → List[str][source]¶

Perform a DNS lookup for A and AAAA records for the given name.

Parameters: name (str) – the name to resolve.
Returns: the list of IPv4 and IPv6 addresses as strings returned by the DNS response.
Return type: list
Raises: wmflib.dns.DnsNotFound – when no address is found.

resolve_ptr(address: str) → List[str][source]¶

Perform a DNS lookup for PTR record for the given address.

Parameters: address (str) – the IPv4 or IPv6 address to resolve.
Returns: the list of absolute target PTR records as strings, without the trailing dot.
Return type: list

resolve_cname(name: str) → str[source]¶

Perform a DNS lookup for CNAME record for the given name.

Parameters: name (str) – the name to resolve.
Returns: the absolute target name for this CNAME, without the trailing dot.
Return type: str

resolve(qname: Union[str, dns.name.Name], record_type: str) → dns.resolver.Answer[source]¶

Perform a DNS lookup for the given qname and record type.

Parameters

qname (str) – the name or address to resolve.
record_type (str) – the DNS record type to lookup for, like ‘A’, ‘AAAA’, ‘PTR’, etc.

Returns

the DNS response.

Return type

dns.resolver.Answer

Raises

wmflib.dns.DnsNotFound – if there are no records for the given record type but the qname has records for different record type(s).
wmflib.dns.DnsError – on generic error.

_resolve_addresses(name: str, record_type: str) → List[str][source]¶

Extract and return all the matching addresses for the given name and record type.

Parameters

name (str) – the name to resolve.
record_type (str) – the DNS record type to lookup for, like ‘A’ and ‘AAAA’.

Returns

the list of IPv4 or IPv6 addresses as strings returned by the DNS response.

Return type

list

static _parse_targets(response_set: dns.rrset.RRset) → List[str][source]¶

Extract and return all the matching names from the given rrset without the trailing dot.

Parameters: response_set (dns.rrset.RRset) – the RRset to parse.
Returns: the list of absolute target record names as strings without the trailing dot.
Return type: list
Raises: wmflib.dns.DnsError – if a relative record is found.

class wmflib.dns.PublicAuthDns[source]¶

Bases: wmflib.dns.Dns

Class to interact with the DNS using the wikimedia foundation authoritative servers.

Initialize the instance.