1 files changed, 76 insertions, 0 deletions
diff --git a/creactistore/_templates/lib/rdflib/plugins/serializers/nt.py b/creactistore/_templates/lib/rdflib/plugins/serializers/nt.py
new file mode 100644
index 0000000..bbbe720
--- /dev/null
+++ b/creactistore/_templates/lib/rdflib/plugins/serializers/nt.py
@@ -0,0 +1,76 @@
+"""
+N-Triples RDF graph serializer for RDFLib.
+See <http://www.w3.org/TR/rdf-testcases/#ntriples> for details about the
+format.
+"""
+from rdflib.serializer import Serializer
+from rdflib.py3compat import b
+import warnings
+
+__all__ = ['NTSerializer']
+
+class NTSerializer(Serializer):
+    """
+    Serializes RDF graphs to NTriples format.
+    """
+
+    def serialize(self, stream, base=None, encoding=None, **args):
+        if base is not None:
+            warnings.warn("NTSerializer does not support base.")
+        if encoding is not None:
+            warnings.warn("NTSerializer does not use custom encoding.")
+        encoding = self.encoding
+        for triple in self.store:
+            stream.write(_nt_row(triple).encode(encoding, "replace"))
+        stream.write(b("\n"))
+
+
+def _nt_row(triple):
+    return u"%s %s %s .\n" % (triple[0].n3(),
+            triple[1].n3(),
+            _xmlcharref_encode(triple[2].n3()))
+
+# from <http://code.activestate.com/recipes/303668/>
+def _xmlcharref_encode(unicode_data, encoding="ascii"):
+    """Emulate Python 2.3's 'xmlcharrefreplace' encoding error handler."""
+    chars = []
+
+    # nothing to do about xmlchars, but replace newlines with escapes: 
+    unicode_data=unicode_data.replace("\n","\\n")
+    if unicode_data.startswith('"""'):
+        # Updated with Bernhard Schandl's patch...
+        # unicode_data = unicode_data.replace('"""', '"')   # original
+
+        last_triplequote_pos = unicode_data.rfind('"""')
+        payload = unicode_data[3:last_triplequote_pos]
+        trail = unicode_data[last_triplequote_pos+3:]
+
+        # fix three-quotes encoding
+        payload = payload.replace('\\"""', '"""')
+
+        # corner case: if string ends with " it is already encoded.
+        # so we need to de-escape it before it will be re-escaped in the next step.
+        if payload.endswith('\\"'):
+            payload = payload.replace('\\"', '"')
+
+        # escape quotes in payload
+        payload = payload.replace('"', '\\"')
+
+        # reconstruct result using single quotes
+        unicode_data = '"%s"%s' % (payload, trail)
+
+    # Step through the unicode_data string one character at a time in
+    # order to catch unencodable characters:                          
+    for char in unicode_data:
+        try:
+            char.encode(encoding, 'strict')
+        except UnicodeError:
+            if ord(char) <= 0xFFFF:
+                chars.append('\\u%04X' % ord(char))
+            else:
+                chars.append('\\U%08X' % ord(char))
+        else:
+            chars.append(char)
+
+    return ''.join(chars)
+