A parsing library for RIPE Atlas measurement results
RIPE Atlas generates a lot of data, and the format of that data changes over
time. Often you want to do something simple like fetch the median RTT for each
measurement result between date X
and date Y
. Unfortunately, there are
dozens of edge cases to account for while parsing the JSON, like the format of
errors and firmware upgrades that changed the format entirely.
To make this easier for our users (and for ourselves), we wrote an easy to use parser that's smart enough to figure out the best course of action for each result, and return to you a useful, native Python object.
The stable version should always be in PyPi, so you can install it with pip
:
.. code:: bash
$ pip install ripe.atlas.sagan
Better yet, make sure you get ujson and sphinx installed with it:
.. code:: bash
$ pip install ripe.atlas.sagan[fast,doc]
Troubleshooting
Some setups (like MacOS) have trouble with building the dependencies required
for reading SSL certificates. If you don't care about SSL stuff and only want to
use sagan to say, parse traceroute or DNS results, then you can do the following:
.. code:: bash
$ SAGAN_WITHOUT_SSL=1 pip install ripe.atlas.sagan
Quickstart: How To Use It
-------------------------
You can parse a result in a few ways. You can just pass the JSON-encoded string:
.. code:: python
from ripe.atlas.sagan import PingResult
my_result = PingResult("<result string from RIPE Atlas ping measurement>")
print(my_result.rtt_median)
123.456
print(my_result.af)
6
You can do the JSON-decoding yourself:
.. code:: python
from ripe.atlas.sagan import PingResult
my_result = PingResult(
json.loads("<result string from RIPE Atlas ping measurement>")
)
print(my_result.rtt_median)
123.456
print(my_result.af)
6
You can let the parser guess the right type for you, though this incurs a small
performance penalty:
.. code:: python
from ripe.atlas.sagan import Result
my_result = Result.get("<result string from RIPE Atlas ping measurement>")
print(my_result.rtt_median)
123.456
print(my_result.af)
6
What it supports
----------------
Essentially, we tried to support everything. If you pass in a DNS result string,
the parser will return a ``DNSResult`` object, which contains a list of
``Response``'s, each with an ``abuf`` property, as well as all of the
information in that abuf: header, question, answer, etc.
.. code:: python
from ripe.atlas.sagan import DnsResult
my_dns_result = DnsResult("<result string from a RIPE Atlas DNS measurement>")
my_dns_result.responses[0].abuf # The entire string
my_dns_result.responses[0].abuf.header.arcount # Decoded from the abuf
We do the same sort of thing for SSL measurements, traceroutes, everything. We
try to save you the effort of sorting through whatever is in the result.
Which attributes are supported?
Every result type has its own properties, with a few common between all types.
Specifically, these attributes exist on all *Result
objects:
created
An datetime object of the
timestamp
fieldmeasurement_id
probe_id
firmware
An integer representing the firmware versionorigin
The from
attribute in the resultis_error
Set to True
if an error was foundAdditionally, each of the result types have their own properties, like
packet_size
, responses
, certificates
, etc. You can take a look at
the classes themselves, or just look at the tests if you're curious. But to get
you started, here are some examples:
.. code:: python
# Ping
ping_result.packets_sent # Int
ping_result.rtt_median # Float, rounded to 3 decimal places
ping_result.rtt_average # Float, rounded to 3 decimal places
# Traceroute
traceroute_result.af # 4 or 6
traceroute_result.total_hops # Int
traceroute_result.destination_address # An IP address string
# DNS
dns_result.responses # A list of Response objects
dns_result.responses[0].response_time # Float, rounded to 3 decimal places
dns_result.responses[0].headers # A list of Header objects
dns_result.responses[0].headers[0].nscount # The NSCOUNT value for the first header
dns_result.responses[0].questions # A list of Question objects
dns_result.responses[0].questions[0].type # The TYPE value for the first question
dns_result.responses[0].abuf # The raw, unparsed abuf string
# SSL Certificates
ssl_result.af # 4 or 6
ssl_result.certificates # A list of Certificate objects
ssl_result.certificates[0].checksum # The checksum for the first certificate
# HTTP
http_result.af # 4 or 6
http_result.uri # A URL string
http_result.responses # A list of Response objects
http_result.responses[0].body_size # The size of the body of the first response
# NTP
ntp_result.af # 4 or 6
ntp_result.stratum # Statum id
ntp_result.version # Version number
ntp_result.packets[0].final_timestamp # A float representing a high-precision NTP timestamp
ntp_result.rtt_median # Median value for packets sent & received
As you might have guessed, with all of this magic going on under the hood, there are a few dependencies:
cryptography
_ (Optional: see "Troubleshooting" above)python-dateutil
_pytz
_IPy
_Additionally, we recommend that you also install ujson
as it will speed up
the JSON-decoding step considerably, and sphinx
if you intend to build the
documentation files for offline use.
There's a full battery of tests for all measurement types, so if you've made changes and would like to submit a pull request, please run them (and update them!) before sending your request:
.. code:: bash
$ python setup.py test
You can also install tox
to test everything in all of the supported Python
versions:
.. code:: bash
$ pip install tox
$ tox
Complete documentation can always be found on Read the Docs
_,
and if you're not online, the project itself contains a docs
directory --
everything you should need is in there.
Sagan is actively maintained by the RIPE NCC and primarily developed by Daniel Quinn
, while the abuf parser is mostly the responsibility of Philip Homburg
with an assist from Bert Wijnen and Rene Wilhelm who contributed to the original
script. Andreas Stirkos
did the bulk of the work on NTP measurements and
fixed a few bugs, and big thanks go to Chris Amin
, John Bond
, and
Pier Carlo Chiodi
for finding and fixing stuff where they've run into
problems.
But why "Sagan
_"? The RIPE Atlas team decided to name all of its modules after
explorers, and what better name for a parser than that of the man who spent
decades reaching out to the public about the wonders of the cosmos?
.. _python-dateutil: https://pypi.python.org/pypi/python-dateutil .. _cryptography: https://pypi.python.org/pypi/cryptography .. _pytz: https://pypi.python.org/pypi/pytz .. _IPy: https://pypi.python.org/pypi/IPy/ .. _ujson: https://pypi.python.org/pypi/ujson .. _sphinx: https://pypi.python.org/pypi/Sphinx .. _Read the Docs: http://ripe-atlas-sagan.readthedocs.org/en/latest/ .. _Daniel Quinn: https://github.com/danielquinn .. _Philip Homburg: https://github.com/philiphomburg .. _Andreas Stirkos: https://github.com/astrikos .. _Chris Amin: https://github.com/chrisamin .. _John Bond: https://github.com/b4ldr .. _Pier Carlo Chiodi: https://github.com/pierky .. _Sagan: https://en.wikipedia.org/wiki/Carl_Sagan .. |Build Status| image:: https://travis-ci.org/RIPE-NCC/ripe.atlas.sagan.png?branch=master :target: https://travis-ci.org/RIPE-NCC/ripe.atlas.sagan .. |Documentation| image:: https://readthedocs.org/projects/ripe-atlas-sagan/badge/?version=latest :target: http://ripe-atlas-sagan.readthedocs.org/en/latest/?badge=latest :alt: Documentation Status