dnserver
Simple DNS server written in python for use in development and testing.
The DNS serves its own records, if none are found it proxies the request to an upstream DNS server
eg. CloudFlare at 1.1.1.1
.
You can set up records you want to serve with a custom zones.toml
file,
see example_zones.toml an example.
Installation from PyPI
Install with:
pip install dnserver
Usage:
dnserver --help
(or python -m dnserver --help
)
For example, to serve a file called my_zones.toml
file on port 5053
, run:
dnserver --port 5053 my_zones.toml
Usage with Python
from dnserver import DNSServer
server = DNSServer.from_toml('example_zones.toml', port=5053)
server.start()
assert server.is_running
# now you can do some requests with your favorite dns library
server.stop()
Usage with Docker
To use with docker:
docker run -p 5053:53/udp -p 5053:53/tcp --rm samuelcolvin/dnserver
(See dnserver on hub.docker.com)
Or with a custom zone file:
docker run -p 5053:53/udp -v `pwd`/zones.toml:/zones/zones.toml --rm samuelcolvin/dnserver
(assuming you have your zone records at ./zones.toml
,
TCP isn't required to use dig
, hence why it's omitted in this case.)
You can then test (either of the above) with
~ ➤ dig @localhost -p 5053 example.com MX
...
;; ANSWER SECTION:
example.com. 300 IN MX 5 whatever.com.
example.com. 300 IN MX 10 mx2.whatever.com.
example.com. 300 IN MX 20 mx3.whatever.com.
;; Query time: 2 msec
;; SERVER: 127.0.0.1#5053(127.0.0.1)
;; WHEN: Sun Feb 26 18:14:52 GMT 2017
;; MSG SIZE rcvd: 94
~ ➤ dig @localhost -p 5053 tutorcruncher.com MX
...
;; ANSWER SECTION:
tutorcruncher.com. 299 IN MX 10 aspmx2.googlemail.com.
tutorcruncher.com. 299 IN MX 5 alt1.aspmx.l.google.com.
tutorcruncher.com. 299 IN MX 5 alt2.aspmx.l.google.com.
tutorcruncher.com. 299 IN MX 1 aspmx.l.google.com.
tutorcruncher.com. 299 IN MX 10 aspmx3.googlemail.com.
;; Query time: 39 msec
;; SERVER: 127.0.0.1#5053(127.0.0.1)
;; WHEN: Sun Feb 26 18:14:48 GMT 2017
;; MSG SIZE rcvd: 176
You can see that the first query took 2ms and returned results from example_zones.toml
,
the second query took 39ms as dnserver didn't have any records for the domain so had to proxy the query to
the upstream DNS server.