Source Code for Module oort.util.graphs

 1  #======================================================================= 
 2  import os 
 3  from os.path import splitext, expanduser 
 4  import logging 
 5  from rdflib import Namespace, Literal 
 6  #======================================================================= 
 7  # TODO: optional hook for inference -- with e.g. FuXi? 
 8   
 9  _logger = logging.getLogger(name=__name__) 
10   
11   
12  OUG_NS = Namespace('tag:oort.to,2006:system/util/graphs#') 
13  LAST_MOD = OUG_NS.lastmodified 
14   
15   
16 -def load_if_modified(graph, fpath, format): 
17      dataUri = graph.absolutize(fpath) 
18      modTime = os.stat(fpath).st_mtime 
19      try: 
20          loadedModValue = graph.value(dataUri, LAST_MOD) 
21          loadedModTime = float(loadedModValue) 
22      except TypeError: 
23          loadedModTime = -1 
24      if modTime > loadedModTime: 
25          graph.remove((dataUri, LAST_MOD, loadedModValue)) 
26          graph.remove_context(graph.context_id(dataUri)) 
27          _logger.info("Loading: <%s>" % fpath) 
28          graph.load(fpath, publicID=dataUri, format=format) 
29          graph.add((dataUri, LAST_MOD, Literal(modTime))) 
30   
31   
32  DEFAULT_FORMAT_MAP = { 
33          'rdf': 'xml', 
34          'n3': 'n3', 
35          'ttl': 'n3', 
36          'xhtml': 'rdfa', 
37          'html': 'rdfa', 
38      } 
39   
40 -def get_format(fpath, fmap=None): 
41      fmap = fmap or DEFAULT_FORMAT_MAP 
42      ext = splitext(fpath)[-1][1:] 
43      return fmap.get(ext) 
44   
45   
46 -def loader(graph, base=None, formatMap=None): 
47      if base: base = expanduser(base) + '%s' 
48      def load_data(fpath): 
49          if base: 
50              fpath = base % fpath 
51          load_if_modified(graph, fpath, format=get_format(fpath, formatMap)) 
52      return load_data 
53   
54   
55 -def load_dir(graph, basedir, formatMap=None, errorHandler=None): 
56      basedir = expanduser(basedir) 
57      for base, fdirs, fnames in os.walk(basedir): 
58          for fname in fnames: 
59              fpath = os.path.join(base, fname) 
60              format = get_format(fpath, formatMap) 
61              if not format: 
62                  continue 
63              try: 
64                  load_if_modified(graph, fpath, format) 
65              except Exception, e: 
66                  if errorHandler: 
67                      errorHandler(e, fpath) 
68                  else: 
69                      raise e 
70