SesameQuery

class pyvo.nameresolver.sesame.SesameQuery(baseurl=None)[source]

Bases: object

a class for preparing a query to a sesame service. Query constraints are added via properties. The execute() function will submit the query and return the results.

The base URL for the query can be changed via the baseurl property.

initialize the query object with a baseurl

Parameters:

baseurl : str

the service endpoint. If None, the value of the module attribute, default_endpoint will be used. (see also set_default_endpoint().)

Attributes Summary

aliases a boolean indicating whether to return all known identifiers for
baseurl the base URL that this query will be sent to when one of the
database_codes
dbs the database selection argument. This is a sequence of any of the
fluxes a boolean indicating whether to return all known identifiers for
ignorecache boolean indicating whether the database caches will be ignored when
names the list of the object names to resolve
opts the options that control the content and format of the output.

Methods Summary

execute() execute the query and return a list Target instances, one for
execute_stream([format, astext, lax]) submit the query and return the raw file stream
getqueryurl([lax, format, astext]) return the GET URL that encodes the current query. This is the
useDatabases(\*args) use the given databases to resolve the names. The arguments are
useDefaultDatabase() clear any previously set database selection so as to use the

Attributes Documentation

aliases

a boolean indicating whether to return all known identifiers for the resolved source. If false, only the main designation will be returned.

baseurl

the base URL that this query will be sent to when one of the execute functions is called.

database_codes = {'simbad': 'S', 'vizier': 'V', 'ned': 'N', 'all': 'A'}
dbs

the database selection argument. This is a sequence of any of the following characters, indicating which databases to query:

S Simbad
V Vizier
N NED
A All of the above

Without A included, only the result from the database returning a matched result will be returned. A value preceded by a ‘~’ requests that the result cache be ignored.

No syntax checking is done on this value upon setting (though it is done via getqueryurl when lax=false); consider using useDatabases().

fluxes

a boolean indicating whether to return all known identifiers for the resolved source. If false, only the main designation will be returned.

ignorecache

boolean indicating whether the database caches will be ignored when retrieving results. If true, the databases will queried directly; otherwise, the cache will be consulted first.

names

the list of the object names to resolve

opts

the options that control the content and format of the output.

Methods Documentation

execute()[source]

execute the query and return a list Target instances, one for each requested target.

Raises:

DALServiceError

for errors connecting to or communicating with the service

DALQueryError

for errors in the input query syntax

DALFormatError

if the XML response is corrupted

execute_stream(format=None, astext=False, lax=False)[source]

submit the query and return the raw file stream

Parameters:

format : str

a format code for the return results, overriding the default XML format. The value should be one or “x”, “x4”, “x2”, “t”. The first three are different versions of the XML formats, and “pc” is the default percent-code format.

astext : bool

request results be returned with a MIME-type of “text/plain”, regardless of the format.

lax : bool

if False (default), a DALQueryError exception will be raised if the current set of parameters cannot be used to form a legal query. This implementation does no syntax checking; thus, this argument is ignored.

Raises:

DALServiceError

for errors connecting to or communicating with the service

DALQueryError

for errors in the input query syntax

getqueryurl(lax=False, format=None, astext=False)[source]

return the GET URL that encodes the current query. This is the URL that the execute functions will use if called next.

Parameters:

lax : bool

if False (default), a DALQueryError exception will be raised if the current set of parameters cannot be used to form a legal query. This implementation does no syntax checking; thus, this argument is ignored.

format : str

a format code for the return results, overriding the default XML format. The value should be one or “x”, “x4”, “x2”, “t”. The first three are different versions of the XML formats, and “pc” is the default percent-code format.

astext : bool

request results be returned with a MIME-type of text/plain”, regardless of the format.

Raises:

DALQueryError

when lax=False, for errors in the input query syntax

useDatabases(*args)[source]

use the given databases to resolve the names. The arguments are database names that are case-insensitive, minimum matches to any of ["Simbad", "NED", "Vizier", "all"]. The order indicates the order that the databases will be checked. Unless “all” is included, Only the result from the first database returning a positive result will be returned by the query.

useDefaultDatabase()[source]

clear any previously set database selection so as to use the default database (Simbad) to resolve the targets.