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########################################################################
# $Header: /var/local/cvsroot/4Suite/Ft/Server/Client/Commands/Rdf/Versa.py,v 1.16 2004/09/23 20:53:30 mbrown Exp $
"""
Implementation of '4ss rdf versa' command
(functions defined here are used by the Ft.Lib.CommandLine framework)
Copyright 2004 Fourthought, Inc. (USA).
Detailed license and copyright information: http://4suite.org/COPYRIGHT
Project home, documentation, distributions: http://4suite.org/
"""
__doc__ = """This command performs a query on the combined user and
system RDF models, using the Versa query language for RDF. \
If necessary, you will be prompted first for credentials and access \
info to connect to the repository."""
import sys, cStringIO, codecs
from Ft.Lib import Uri
from Ft.Rdf._4versa import PrettyPrintResults, BASE_NS_MAP
from Ft.Rdf.Parsers.Versa import Util as VersaUtil
from Ft.Rdf.Statement import Statement
from Ft.Server.Client.Commands import CommandUtil
from Ft.Server.Common import Util
#DASHBOARD_NS = "http://chimezie.ogbuji.net/4ss/tools/dashboard/schema#"
#NSM_NSM = {'fres': 'http://xmlns.4suite.org/reserved'}
#PREFIXES = XPath.Compile("/fres:NsMappings/fres:NsMapping/Prefix/text()")
#URIS = XPath.Compile("/fres:NsMappings/fres:NsMapping/Uri/text()")
def Run(options, args):
quiet = options.get('quiet')
scope = options.get('scope')
repo = CommandUtil.GetRepository(options, '4ss.rdf.versa')
if repo is not None:
try:
model = repo.getModel()
if not options.get('no-mapping-file'):
ns_map = Util.GetUserNsMappings(repo, BASE_NS_MAP)
else:
ns_map = {}
srcFile = options.get('query-file')
#Read in the query
if srcFile:
stream = Uri.BASIC_RESOLVER.resolve(srcFile)
con = FakeContext(model, ns_map, {}, scope=scope)
result = VersaUtil.ProcessQueryFile(
stream, con, sys.stderr, queryFunction=QueryFunction
)
stream = cStringIO.StringIO()
enc, dec, rdr, wrtr = codecs.lookup("utf-8")
stream = wrtr(stream)
VersaUtil.ResultsToXml(result, stream)
result = stream.getvalue()
else:
query = args.get('query', None)
if not query:
sys.stderr.write("Enter Query: ")
query = sys.stdin.readline()
sys.stderr.write("\n")
if not quiet:
sys.stderr.write("Executing Query:\n")
sys.stderr.write(query+'\n')
if not quiet and ns_map:
sys.stderr.write("With the following namepace mappings:\n")
for name, value in ns_map.items():
sys.stderr.write("%s --> %s\n" % (name, value))
result = model.versaQuery(query, ns_map)
print result
finally:
try:
repo.txRollback()
except:
pass
return
def QueryFunction(query, context, scope=None):
results = context.model.versaQueryRaw(query, context.nsMapping,
context.varBindings, scope)
return results
class FakeContext:
"""For accommodation of the interface of Ft.Rdf.Parsers.Versa.Util.ProcessQueryFile"""
def __init__(self, model, nsMapping, varBindings, scope):
self.model = model
self.nsMapping = nsMapping
self.varBindings = varBindings
self.scope = scope
return
def clone(self):
new_con = self.__class__(self.model, self.nsMapping.copy(),
self.varBindings.copy(), self.scope)
return new_con
def Register():
from Ft.Lib.CommandLine import Options, Command, Arguments
cmd = Command.Command('versa',
'Perform a Versa query',
'--query-file=',
__doc__,
function = Run,
arguments = [
Arguments.OptionalArgument('query',
'The query to perform. Required if --file is not specified',
str),
],
options = Options.Options([
Options.Option('q', 'quiet', 'Present no output except for errors or any result'),
Options.Option('f', 'query-file=', 'A file with the Versa query'),
Options.Option(None, 'no-mapping-file', "Do not use the user's namespace mapping file"),
Options.Option(None, 'scope=scope', 'a scope to restrict the query',),
]),
fileName = __file__,
)
return cmd
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