Source Code for Module gavo.grammars.votablegrammar

 1  """ 
 2  A grammar taking its rows from a VOTable. 
 3  """ 
 4   
 5  #c Copyright 2008-2019, the GAVO project 
 6  #c 
 7  #c This program is free software, covered by the GNU GPL.  See the 
 8  #c COPYING file in the source distribution. 
 9   
10   
11  # XXX TODO: return PARAMs as the docrow 
12   
13   
14  import gzip 
15   
16  from gavo import base 
17  from gavo import votable 
18  from gavo.base import valuemappers 
19  from gavo.grammars import common 
20   
21   
22 -class VOTableRowIterator(common.RowIterator): 
23          """An iterator returning rows of the first table within a VOTable. 
24          """ 
25 -        def __init__(self, grammar, sourceToken, **kwargs): 
26                  common.RowIterator.__init__(self, grammar, sourceToken, **kwargs) 
27                  if self.grammar.gunzip: 
28                          inF = gzip.open(sourceToken) 
29                  else: 
30                          inF = open(sourceToken) 
31                  self.rowSource = votable.parse(inF).next() 
32   
33 -        def _iterRows(self): 
34                  nameMaker = valuemappers.VOTNameMaker() 
35                  fieldNames = [nameMaker.makeName(f)  
36                          for f in self.rowSource.tableDefinition. 
37                                          iterChildrenOfType(votable.V.FIELD)] 
38                  for row in self.rowSource: 
39                          yield dict(zip(fieldNames, row)) 
40                  self.grammar = None 
41   
42 -        def getLocator(self): 
43                  return "VOTable file %s"%self.sourceToken 
44   
45   
46 -class VOTableGrammar(common.Grammar): 
47          """A grammar parsing from VOTables. 
48   
49          Currently, the PARAM fields are ignored, only the data rows are 
50          returned. 
51   
52          voTableGrammars result in typed records, i.e., values normally come 
53          in the types they are supposed to have. 
54          """ 
55          name_ = "voTableGrammar" 
56          _gunzip = base.BooleanAttribute("gunzip", description="Unzip sources" 
57                  " while reading?", default=False) 
58   
59          rowIterator = VOTableRowIterator 
60