spacetrack documentation¶

spacetrack is a Python client for Space-Track, with methods for all request classes, keyword validation for request predicates, streaming download support, and automatic rate limiting.

Contents:

Installation¶

The recommended installation method is using pip.

pip¶

$ pip install spacetrack

To install with asyncio support, install the async extra:

$ pip install spacetrack[async]

Git¶

$ git clone https://github.com/python-astrodynamics/spacetrack.git
Cloning into 'spacetrack'...

Check out a release tag

$ cd spacetrack
$ git checkout 0.13.7

Usage¶

import spacetrack.operators as op
from spacetrack import SpaceTrackClient

st = SpaceTrackClient(identity='user@example.com', password='password')

Request classes are presented as methods on the SpaceTrackClient object. For example, st.tle_publish(). Each request class is part of a request controller. Since most request classes are only part of one request controller, spacetrack looks up the controller for you. It can be specified explicitly in several ways. All the following are equivalent:

st.tle_publish()
st.tle_publish(controller='basicspacedata')
st.basicspacedata.tle_publish()
st.generic_request('tle_publish')
st.generic_request('tle_publish', controller='basicspacedata')

Request predicates are passed as keyword arguments. Valid arguments can be checked using the get_predicates() method. The following are equivalent:

st.tle_publish.get_predicates()
st.tle_publish.get_predicates(controller='basicspacedata')
st.basicspacedata.tle_publish.get_predicates()
st.basicspacedata.get_predicates('tle_publish')
st.get_predicates('tle_publish')
st.get_predicates('tle_publish', controller='basicspacedata')

Returned object:

[Predicate(name='publish_epoch', type_='datetime', nullable=False),
 Predicate(name='tle_line1', type_='str', nullable=False),
 Predicate(name='tle_line2', type_='str', nullable=False)]

Internally, the client uses this mechanism to verify the keyword arguments. Types are not currently checked.

Streaming Downloads¶

It is possible to stream responses by passing iter_content=True (100 KiB chunks) or iter_lines=True to the request class methods.

Example¶

The same example is shown below synchronously and asynchronously.

import spacetrack.operators as op
from spacetrack import SpaceTrackClient

st = SpaceTrackClient(identity='user@example.com', password='password')

data = st.tle_latest(iter_lines=True, ordinal=1, epoch='>now-30',
                     mean_motion=op.inclusive_range(0.99, 1.01),
                     eccentricity=op.less_than(0.01), format='tle')

with open('tle_latest.txt', 'w') as fp:
    for line in data:
        fp.write(line + '\n')

import asyncio

import spacetrack.operators as op
from spacetrack.aio import AsyncSpaceTrackClient


async def download_latest_tles():
    st = AsyncSpaceTrackClient(identity='user@example.com',
                               password='password')

    with st:
        data = await st.tle_latest(
            iter_lines=True, ordinal=1, epoch='>now-30',
            mean_motion=op.inclusive_range(0.99, 1.01),
            eccentricity=op.less_than(0.01), format='tle')

        with open('tle_latest.txt', 'w') as fp:
            async for line in data:
                fp.write(line + '\n')

loop = asyncio.get_event_loop()
loop.run_until_complete(download_latest_tles())

File Uploads¶

To use the upload request class, pass a file keyword argument with the opened file:

from spacetrack import SpaceTrackClient

st = SpaceTrackClient(identity='user@example.com', password='password')

with open('somefile.txt', 'rb') as fp:
    st.upload(file=fp)

Rate Limiter¶

“Space-track throttles API use in order to maintain consistent performance for all users. To avoid error messages, please limit your query frequency to less than 20 requests per minute.”

The client will ensure that no more than 19 HTTP requests are sent per minute by sleeping if the rate exceeds this. This will be logged to the spacetrack module’s logger. You can register a callback with the SpaceTrackClient or AsyncSpaceTrackClient classes. It will be passed the time that the module is sleeping until, in seconds since the epoch (as with time.time()).

import time

from spacetrack import SpaceTrackClient

def mycallback(until):
    duration = int(round(until - time.time()))
    print('Sleeping for {:d} seconds.'.format(duration))

st = SpaceTrackClient(identity='user@example.com', password='password')
st.callback = mycallback

Sample Queries¶

The Space-Track website lists some sample queries, which are shown here using the Python module.

output = st.boxscore(format='csv')

decay_epoch = op.inclusive_range(date(2012, 7, 2), date(2012, 7, 9))
st.decay(decay_epoch=decay_epoch, orderby=['norad_cat_id', 'precedence'], format='xml')

st.satcat(launch='>now-7', current='Y', orderby='launch desc', format='html')

st.satcat(period=op.inclusive_range(1430, 1450), current='Y',
          decay=None, orderby='norad_cat_id', format='html')

st.satcat(period=op.less_than(128), decay=None, current='Y')

st.tle_latest(ordinal=1, epoch='>now-30',
              mean_motion=op.inclusive_range(0.99, 1.01),
              eccentricity=op.less_than(0.01), format='tle')

st.tle_latest(ordinal=1, epoch='>now-30', mean_motion=op.greater_than(11.25),
              format='3le')

st.tle_latest(favorites='Amateur', ordinal=1, epoch='>now-30', format='3le')

st.tle_latest(
    ordinal=1,
    norad_cat_id=[
        36000,
        op.inclusive_range(36001, 36004),
        op.like(36005),
        op.startswith(3600),
        36010
    ],
    orderby='norad_cat_id',
    format='html')

st.tle(norad_cat_id=25544, orderby='epoch desc', limit=22, format='tle')

st.omm(norad_cat_id=25544, orderby='epoch desc', limit=22, format='xml')

st.tip(norad_cat_id=[60, 38462, 38351], format='html')

st.cdm(constellation='iridium', limit=10, orderby='creation_date desc', format='html')

st.cdm(constellation='iridium', limit=10, orderby='creation_date desc', format='kvn')

st.cdm(
    constellation='intelsat', tca='>now',
    predicates=['message_for', 'tca', 'miss_distance'],
    orderby='miss_distance', format='html', metadata=True)

st.cdm(
    constellation='intelsat', tca='>now',
    predicates=['message_for', 'tca', 'miss_distance'],
    orderby='miss_distance', format='kvn')

Module Reference¶

SpaceTrack¶

exception spacetrack.base.AuthenticationError[source]¶: Space-Track authentication error.

exception spacetrack.base.UnknownPredicateTypeWarning[source]¶: Used to warn when a predicate type is unknown.

class spacetrack.base.Predicate(name, type_, nullable=False, default=None, values=None)[source]¶

Hold Space-Track predicate information.

The current goal of this class is to print the repr for the user.

class spacetrack.base.SpaceTrackClient(identity, password, base_url='https://www.space-track.org/')[source]¶

SpaceTrack client class.

Parameters:	identity – Space-Track username. password – Space-Track password. base_url – May be overridden to use e.g. https://testing.space-track.org/

For more information, refer to the Space-Track documentation.

request_controllers¶

Ordered dictionary of request controllers and their request classes in the following order.

basicspacedata
expandedspacedata
fileshare
spephemeris

For example, if the spacetrack.file method is used without specifying which controller, the client will choose the fileshare controller (which comes before spephemeris).

Note

If new request classes and/or controllers are added to the Space-Track API but not yet to this library, you can safely subclass SpaceTrackClient with a copy of this ordered dictionary to add them.

That said, please open an issue on GitHub for me to add them to the library.

session = None¶: requests.Session instance. It can be mutated to configure e.g. proxies.

authenticate()[source]¶

Authenticate with Space-Track.

Raises:	`spacetrack.base.AuthenticationError` – Incorrect login details.

Note

This method is called automatically when required.

generic_request(class_, iter_lines=False, iter_content=False, controller=None, parse_types=False, **kwargs)[source]¶

Generic Space-Track query.

The request class methods use this method internally; the public API is as follows:

st.tle_publish(*args, **kw)
st.basicspacedata.tle_publish(*args, **kw)
st.file(*args, **kw)
st.fileshare.file(*args, **kw)
st.spephemeris.file(*args, **kw)

They resolve to the following calls respectively:

st.generic_request('tle_publish', *args, **kw)
st.generic_request('tle_publish', *args, controller='basicspacedata', **kw)
st.generic_request('file', *args, **kw)
st.generic_request('file', *args, controller='fileshare', **kw)
st.generic_request('file', *args, controller='spephemeris', **kw)

Parameters:	class_ – Space-Track request class name iter_lines – Yield result line by line iter_content – Yield result in 100 KiB chunks. controller – Optionally specify request controller to use. parse_types – Parse string values in response according to type given in predicate information, e.g. `'2017-01-01'` -> `datetime.date(2017, 1, 1)`. **kwargs – These keywords must match the predicate fields on Space-Track. You may check valid keywords with the following snippet: spacetrack = SpaceTrackClient(...) spacetrack.tle.get_predicates() # or spacetrack.get_predicates('tle') See `_stringify_predicate_value()` for which Python objects are converted appropriately.
Yields:	Lines—stripped of newline characters—if `iter_lines=True`
Yields:	100 KiB chunks if `iter_content=True`
Returns:	Parsed JSON object, unless `format` keyword argument is passed. Warning Passing `format='json'` will return the JSON unparsed. Do not set `format` if you want the parsed JSON object returned!

get_predicates(class_, controller=None)[source]¶: Get full predicate information for given request class, and cache for subsequent calls.

Experimental `asyncio` API¶

Warning

The asyncio API is not thoroughly unit tested, use with caution. Please report issues on GitHub.

class spacetrack.aio.AsyncSpaceTrackClient(identity, password, base_url='https://www.space-track.org/')[source]¶

Bases: spacetrack.base.SpaceTrackClient

Asynchronous SpaceTrack client class.

This class should be considered experimental.

It must be closed by calling close(). Alternatively, instances of this class can be used as a context manager.

Parameters:	identity – Space-Track username. password – Space-Track password. base_url – May be overridden to use e.g. https://testing.space-track.org/

For more information, refer to the Space-Track documentation.

session¶: aiohttp.ClientSession instance.

close()[source]¶: Close aiohttp session.

authenticate()[source]¶

Authenticate with Space-Track.

Raises:	`spacetrack.base.AuthenticationError` – Incorrect login details.

Note

This method is called automatically when required.

generic_request(class_, iter_lines=False, iter_content=False, controller=None, parse_types=False, **kwargs)[source]¶

Generic Space-Track query coroutine.

The request class methods use this method internally; the public API is as follows:

st.tle_publish(*args, **st)
st.basicspacedata.tle_publish(*args, **st)
st.file(*args, **st)
st.fileshare.file(*args, **st)
st.spephemeris.file(*args, **st)

They resolve to the following calls respectively:

st.generic_request('tle_publish', *args, **st)
st.generic_request('tle_publish', *args, controller='basicspacedata', **st)
st.generic_request('file', *args, **st)
st.generic_request('file', *args, controller='fileshare', **st)
st.generic_request('file', *args, controller='spephemeris', **st)

Parameters:	class – Space-Track request class name iter_lines – Yield result line by line iter_content – Yield result in 100 KiB chunks. controller – Optionally specify request controller to use. parse_types – Parse string values in response according to type given in predicate information, e.g. `'2017-01-01'` -> `datetime.date(2017, 1, 1)`. **kwargs – These keywords must match the predicate fields on Space-Track. You may check valid keywords with the following snippet: spacetrack = AsyncSpaceTrackClient(...) await spacetrack.tle.get_predicates() # or await spacetrack.get_predicates('tle') See `_stringify_predicate_value()` for which Python objects are converted appropriately.
Yields:	Lines—stripped of newline characters—if `iter_lines=True`
Yields:	100 KiB chunks if `iter_content=True`
Returns:	Parsed JSON object, unless `format` keyword argument is passed. Warning Passing `format='json'` will return the JSON unparsed. Do not set `format` if you want the parsed JSON object returned!

get_predicates(class_, controller=None)[source]¶: Get full predicate information for given request class, and cache for subsequent calls.

SpaceTrack operators¶

Refer to REST Operators in the Space-Track documentation.

spacetrack.operators.greater_than(value)[source]¶: '>value'.

spacetrack.operators.less_than(value)[source]¶: '<value'.

spacetrack.operators.not_equal(value)[source]¶: '<>value'.

spacetrack.operators.inclusive_range(left, right)[source]¶: 'left--right'.

spacetrack.operators.like(value)[source]¶: '~~value'.

spacetrack.operators.startswith(value)[source]¶: '^value'.

spacetrack.operators._stringify_predicate_value(value)[source]¶

Convert Python objects to Space-Track compatible strings

Booleans (True -> 'true')
Sequences ([25544, 34602] -> '25544,34602')
dates/datetimes (date(2015, 12, 23) -> '2015-12-23')
None -> 'null-val'

Change Log¶

Unreleased ¶

N/A

0.13.7 ¶

Added¶

Support for the general perturbations (gp) class.

0.13.6 ¶

Fixed¶

Regression in 0.13 that prevented spephemeris/download from working by trying to load a model definition which it doesn’t have.

0.13.5 ¶

Fixed¶

The ‘text’ predicate type is now understood.
Unknown predicate types issue a warning instead of raising an exception.

0.13.4 ¶

Added¶

SpaceTrackClient gained a base_url parameter to allow the use of an alternate Space-Track server.

0.13.3 ¶

Fixed¶

The deprecation warning about importing Sequence or Mapping from collections instead of collections.abc.

0.13.2 ¶

Fixed¶

The async extra installs aiohttp 2 because spacetrack is not yet aiohttp 3 compatible.
Deprecation warnings about invalid escape sequences.

0.13.1 ¶

Fixed¶

spacetrack can be installed with setuptools v38.0+, which requires install_requires in setup.py to be ordered.

0.13.0 ¶

Added¶

parse_types flag to optionally parse types as described by the modeldef API.
Compatibility with maneuver and maneuver_history request classes for expandedspacedata request controller.
Compatibility with upload and delete request classes for fileshare request controller. ### Fixed
Predicates with the enum type are parsed correctly. Previously, single-valued enums had None as a second value, and enums with more than two values only had the first and last value due to the regex match not capturing repeated groups. The values aren’t used by spacetrack, so the bug went unnoticed.
Exception on Python 3.5+ in threads without an asyncio event loop (even using the normal SpaceTrackClient). Fixed by requiring ratelimiter >= 1.2.0 ### Changed
Require aiohttp >= 2.0 for the async extra.

0.12.0 ¶

Added¶

Request controller can be passed explicitly to methods that take a request class, because some request classes are present in more than one controller.
Request controller proxy attribute, e.g. SpaceTrackClient.fileshare.file(), which is equivalent to SpaceTrackClient.generic_request('file', controller='fileshare').
dir(SpaceTrackClient(...)) now includes the request controllers and request classes so it’s easier to see what can be called.

Fixed¶

/modeldef API not queried if no predicates are passed. This allows spephemeris/download to be used, which doesn’t have a model definition.

Changed¶

Calling request class methods uses first request controller that matches. The order is stored in the keys of the SpaceTrackClient.request_controllers ordered dict, currently basicspacedata, expandedspacedata, fileshare, spephemeris. Any new request controllers will be added to the end, to preserve lookup order. New request classes that would change the order will accompany a major version bump.
AsyncSpaceTrackClient uses requests’ CA file for same experience with both clients.

0.11.1 ¶

Fixed¶

Bump ratelimiter version to improve rate limiting for AsyncSpaceTrackClient

Changed¶

Documentation included in source distribution.

0.11.0 ¶

Added¶

Some unit tests added for AsyncSpaceTrackClient.

Fixed¶

\r\n to \n newline conversion for async chunk iterator.

Changed¶

AsyncSpaceTrackClient can no longer be imported from the top level spacetrack module, since this would cause an error if optional dependency aiohttp was not installed. It must be imported from spacetrack.aio.

0.10.0 - 2016-02-04¶

Fixed¶

Compatibility with file and download request classes for fileshare request controller. upload request class removed, unable to test.
Rate limit violation HTTP status code 500 handled during predicate information request.

Changed¶

iter_lines=True now raises ValueError if receiving binary data (currently only possible with download request class).
Removed internal method _get_predicate_fields, set comprehension used inline instead.
Predicate class now has a default attribute.

0.9.0 - 2016-01-28¶

First release.

spacetrack documentation¶

Installation¶

pip¶

Git¶

Usage¶

Streaming Downloads¶

Example¶

File Uploads¶

Rate Limiter¶

Sample Queries¶

Module Reference¶

SpaceTrack¶

Experimental asyncio API¶

SpaceTrack operators¶

Change Log¶

Added¶

Fixed¶

Fixed¶

Added¶

Fixed¶

Fixed¶

Fixed¶

Added¶

Added¶

Fixed¶

Changed¶

Fixed¶

Changed¶

Added¶

Fixed¶

Changed¶

0.10.0 - 2016-02-04¶

Fixed¶

Changed¶

0.9.0 - 2016-01-28¶

Indices and tables¶

Experimental `asyncio` API¶