# Licensed under a 3-clause BSD style license - see LICENSE.rst
import warnings
from io import StringIO, BytesIO
from astropy.table import Table
from astropy.io import fits
from astropy import coordinates
from astropy import units as u
from ..query import BaseQuery
from ..utils import commons
from ..utils import async_to_sync
from ..exceptions import InvalidQueryError, NoResultsWarning
from . import conf
__all__ = ['Heasarc', 'HeasarcClass']
[docs]@async_to_sync
class HeasarcClass(BaseQuery):
"""
HEASARC query class.
For a list of available HEASARC mission tables, visit:
https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3catindex.pl
"""
URL = conf.server
TIMEOUT = conf.timeout
coord_systems = ['fk5', 'fk4', 'equatorial', 'galactic']
[docs] def query_async(self, request_payload, cache=True, url=None):
"""
Submit a query based on a given request_payload. This allows detailed
control of the query to be submitted.
"""
if url is None:
url = conf.server
response = self._request('GET', url, params=request_payload,
timeout=self.TIMEOUT, cache=cache)
return response
[docs] def query_mission_list(self, cache=True, get_query_payload=False):
"""
Returns a list of all available mission tables with descriptions
"""
request_payload = self._args_to_payload(
entry='none',
mission='xxx',
displaymode='BatchDisplay'
)
if get_query_payload:
return request_payload
# Parse the results specially (it's ascii format, not fits)
response = self.query_async(
request_payload,
url=conf.server,
cache=cache
)
data_str = response.text
data_str = data_str.replace('Table xxx does not seem to exist!\n\n\n\nAvailable tables:\n', '')
table = Table.read(data_str, format='ascii.fixed_width_two_line',
delimiter='+', header_start=1, position_line=2,
data_start=3, data_end=-1)
return table
[docs] def query_mission_cols(self, mission, cache=True, get_query_payload=False,
**kwargs):
"""
Returns a list containing the names of columns that can be returned for
a given mission table. By default all column names are returned.
Parameters
----------
mission : str
Mission table (short name) to search from
fields : str, optional
Return format for columns from the server available options:
* Standard : Return default table columns
* All (default) : Return all table columns
* <custom> : User defined csv list of columns to be returned
All other parameters have no effect
"""
response = self.query_region_async(position='0.0 0.0', mission=mission,
radius='361 degree', cache=cache,
get_query_payload=get_query_payload,
resultsmax=1,
fields='All')
# Return payload if requested
if get_query_payload:
return response
return self._parse_result(response).colnames
[docs] def query_object_async(self, object_name, mission,
cache=True, get_query_payload=False,
**kwargs):
"""
Query around a specific object within a given mission catalog
Parameters
----------
object_name : str
Object to query around. To set search radius use the 'radius'
parameter.
mission : str
Mission table to search from
**kwargs :
see `~astroquery.heasarc.HeasarcClass._args_to_payload` for list
of additional parameters that can be used to refine search query
"""
request_payload = self._args_to_payload(
mission=mission,
entry=object_name,
**kwargs
)
# Return payload if requested
if get_query_payload:
return request_payload
return self.query_async(request_payload, cache=cache)
[docs] def query_region_async(self, position, mission, radius,
cache=True, get_query_payload=False,
**kwargs):
"""
Query around specific set of coordinates within a given mission
catalog. Method first converts the supplied coordinates into the FK5
reference frame and searches for sources from there. Because of this,
returned offset coordinates may look different than the ones supplied.
Parameters
----------
position : `astropy.coordinates` or str
The position around which to search. It may be specified as a
string in which case it is resolved using online services or as
the appropriate `astropy.coordinates` object. ICRS coordinates
may also be entered as a string.
(adapted from nrao module)
mission : str
Mission table to search from
radius :
Astropy Quantity object, or a string that can be parsed into one.
e.g., '1 degree' or 1*u.degree.
**kwargs :
see `~astroquery.heasarc.HeasarcClass._args_to_payload` for list
of additional parameters that can be used to refine search query
"""
# Convert the coordinates to FK5
c = commons.parse_coordinates(position).transform_to(coordinates.FK5)
kwargs['coordsys'] = 'fk5'
kwargs['equinox'] = 2000
# Generate the request
request_payload = self._args_to_payload(
mission=mission,
entry="{},{}".format(c.ra.degree, c.dec.degree),
radius=u.Quantity(radius),
**kwargs
)
# Return payload if requested
if get_query_payload:
return request_payload
# Submit the request
return self.query_async(request_payload, cache=cache)
def _old_w3query_fallback(self, content):
# old w3query (such as that used in ISDC) return very strange fits, with all ints
f = fits.open(BytesIO(content))
for c in f[1].columns:
if c.disp is not None:
c.format = c.disp
else:
c.format = str(c.format).replace("I", "A")
I = BytesIO()
f.writeto(I)
I.seek(0)
return Table.read(I)
def _fallback(self, text):
"""
Blank columns which have to be converted to float or in fail so
lets fix that by replacing with -1's
"""
data = StringIO(text)
header = fits.getheader(data, 1) # Get header for column info
colstart = [y for x, y in header.items() if "TBCOL" in x]
collens = [int(float(y[1:]))
for x, y in header.items() if "TFORM" in x]
new_table = []
old_table = text.split("END")[-1].strip()
for line in old_table.split("\n"):
newline = []
for n, tup in enumerate(zip(colstart, collens), start=1):
cstart, clen = tup
part = line[cstart - 1:cstart + clen]
newline.append(part)
if len(part.strip()) == 0:
if header["TFORM%i" % n][0] in ["F", "I"]:
# extra space is required to separate column
newline[-1] = "-1".rjust(clen) + " "
new_table.append("".join(newline))
data = StringIO(text.replace(old_table, "\n".join(new_table)))
return Table.read(data, hdu=1)
def _parse_result(self, response, verbose=False):
# if verbose is False then suppress any VOTable related warnings
if not verbose:
commons.suppress_vo_warnings()
if "BATCH_RETRIEVAL_MSG ERROR:" in response.text:
raise InvalidQueryError("One or more inputs is not recognized by HEASARC. "
"Check that the object name is in GRB, SIMBAD+Sesame, or "
"NED format and that the mission name is as listed in "
"query_mission_list().")
elif "Software error:" in response.text:
raise InvalidQueryError("Unspecified error from HEASARC database. "
"\nCheck error message: \n{!s}".format(response.text))
elif "NO MATCHING ROWS" in response.text:
warnings.warn(NoResultsWarning("No matching rows were found in the query."))
return Table()
try:
data = BytesIO(response.content)
table = Table.read(data, hdu=1)
return table
except ValueError:
try:
return self._fallback(response.text)
except Exception as e:
return self._old_w3query_fallback(response.content)
def _args_to_payload(self, **kwargs):
"""
Generates the payload based on user supplied arguments
Parameters
----------
mission : str
Mission table to query
entry : str, optional
Object or position for center of query. A blank value will return
all entries in the mission table. Acceptable formats:
* Object name : Name of object, e.g. 'Crab'
* Coordinates : X,Y coordinates, either as 'degrees,degrees' or
'hh mm ss,dd mm ss'
fields : str, optional
Return format for columns from the server available options:
* Standard (default) : Return default table columns
* All : Return all table columns
* <custom> : User defined csv list of columns to be
returned
radius : float (arcmin), optional
Astropy Quantity object, or a string that can be parsed into one.
e.g., '1 degree' or 1*u.degree.
coordsys: str, optional
If 'entry' is a set of coordinates, this specifies the coordinate
system used to interpret them. By default, equatorial coordinates
are assumed. Possible values:
* 'fk5' <default> (FK5 J2000 equatorial coordinates)
* 'fk4' (FK4 B1950 equatorial coordinates)
* 'equatorial' (equatorial coordinates, `equinox` param
determines epoch)
* 'galactic' (Galactic coordinates)
equinox : int, optional
Epoch by which to interpret supplied equatorial coordinates
(defaults to 2000, ignored if `coordsys` is not 'equatorial')
resultmax : int, optional
Set maximum query results to be returned
sortvar : str, optional
Set the name of the column by which to sort the results. By default
the results are sorted by distance from queried object/position
displaymode : str, optional
Return format from server. Since the user does not interact with
this directly, it's best to leave this alone
action : str, optional
Type of action to be taken (defaults to 'Query')
"""
# User-facing parameters are lower case, while parameters as passed to the HEASARC service are capitalized according to the HEASARC requirements.
# The necessary transformations are done in this function.
# Define the basic query for this object
mission = kwargs.pop('mission')
request_payload = dict(
tablehead=('name=BATCHRETRIEVALCATALOG_2.0 {}'
.format(mission)),
Entry=kwargs.pop('entry', 'none'),
Action=kwargs.pop('action', 'Query'),
displaymode=kwargs.pop('displaymode', 'FitsDisplay'),
resultsmax=kwargs.pop('resultsmax', '10')
)
# Fill in optional information for refined queries
# Handle queries involving coordinates
coordsys = kwargs.pop('coordsys', 'fk5')
equinox = kwargs.pop('equinox', None)
if coordsys.lower() == 'fk5':
request_payload['Coordinates'] = 'Equatorial: R.A. Dec'
elif coordsys.lower() == 'fk4':
request_payload['Coordinates'] = 'Equatorial: R.A. Dec'
request_payload['equinox'] = 1950
elif coordsys.lower() == 'equatorial':
request_payload['Coordinates'] = 'Equatorial: R.A. Dec'
if equinox is not None:
request_payload['Equinox'] = str(equinox)
elif coordsys.lower() == 'galactic':
request_payload['Coordinates'] = 'Galactic: LII BII'
else:
raise ValueError("'coordsys' parameter must be one of {!s}"
.format(self.coord_systems))
# Specify which table columns are to be returned
fields = kwargs.pop('fields', None)
if fields is not None:
if fields.lower() == 'standard':
request_payload['Fields'] = 'Standard'
elif fields.lower() == 'all':
request_payload['Fields'] = 'All'
else:
request_payload['varon'] = fields.lower().split(',')
# Set search radius (arcmin)
radius = kwargs.pop('radius', None)
if radius is not None:
request_payload['Radius'] = "{}".format(u.Quantity(radius).to(u.arcmin))
# Maximum number of results to be returned
resultmax = kwargs.pop('resultmax', None)
if resultmax is not None:
request_payload['ResultMax'] = int(resultmax)
# Set variable for sorting results
sortvar = kwargs.pop('sortvar', None)
if sortvar is not None:
request_payload['sortvar'] = sortvar.lower()
# Time range variable
_time = kwargs.pop('time', None)
if _time is not None:
request_payload['Time'] = _time
if len(kwargs) > 0:
mission_fields = [k.lower() for k in self.query_mission_cols(mission=mission)]
for k, v in kwargs.items():
if k.lower() in mission_fields:
request_payload['bparam_' + k.lower()] = v
else:
raise ValueError("unknown parameter '{}' provided, must be one of {!s}".format(
k,
mission_fields,
))
return request_payload
Heasarc = HeasarcClass()