Simple DNS resolver for asyncio
aiodns provides a simple way for doing asynchronous DNS resolutions with a synchronous looking interface by using pycares.
import asyncio import aiodns loop = asyncio.get_event_loop() resolver = aiodns.DNSResolver(loop=loop) f = resolver.query('google.com','A') result = loop.run_until_complete(f) print(result)
The following query types are supported: A, AAAA, CNAME, MX, NAPTR, NS, PTR, SOA, SRV, TXT.
The library supports both asyncio and Trollius.
If you use use Python 3.5+, you can use the async and await statements:
import asyncio import aiodns loop = asyncio.get_event_loop() resolver = aiodns.DNSResolver(loop=loop) async def query(name, query_type): return await resolver.query(name, query_type) coro = query('google.com', 'A') result = loop.run_until_complete(coro)
If you use Python 3.3/3.4 you may use yield from statement:
@asyncio.coroutine def func(): result = yield from resolver.query('google.com','A')
For Trollius you should use another syntax like:
@trollius.coroutine def func(): result = yield trollius.From(resolver.query('google.com','A'))
The API is pretty simple, three functions are provided in the
query(host, type): Do a DNS resolution of the given type for the given hostname. It returns an instance of
asyncio.Future. The actual result of the DNS query is taken directly from pycares. As of version 1.0.0 of aiodns (and pycares, for that matter) results are always namedtuple-like objects with different attributes. Please check the documentation for the result fields.
gethostbyname(host, socket_family): Do a DNS resolution for the given hostname and the desired type of address family (i.e.
query()always performs a request to a DNS server,
gethostbyname()first looks into
/etc/hostsand thus can resolve local hostnames (such as
localhost). Please check the documentation for the result fields. The actual result of the call is a
cancel(): Cancel all pending DNS queries. All futures will get
DNSErrorexception set, with
Running the test suite
To run the test suite:
Saúl Ibarra Corretgé <firstname.lastname@example.org>
aiodns uses the MIT license, check LICENSE file.
If you'd like to contribute, fork the project, make a patch and send a pull request. Have a look at the surrounding code and please, make yours look alike :-)