Apply Python3 modernize transforms

Main changes:
- use of __future__
- using six lib to:
	- deal with checking unicode
	- dict operations
	- other API changes

Author: manu-chroma

schema_salad/__init__.py

@@ -1,3 +1,4 @@
+from __future__ import absolute_import
 import logging
 import sys
 import typing

schema_salad/__main__.py

@@ -1,3 +1,4 @@
+from __future__ import absolute_import
 from . import main
 import sys
 import typing

schema_salad/jsonld_context.py

@@ -1,7 +1,9 @@
+from __future__ import absolute_import
 import collections
 import shutil
 import json
 import ruamel.yaml as yaml
+import six
 try:
     from ruamel.yaml import CSafeLoader as SafeLoader
 except ImportError:
@@ -40,10 +42,10 @@ def pred(datatype,      # type: Dict[str, Union[Dict, str]]
 
     if split.scheme != '':
         vee = name
-        (ns, ln) = rdflib.namespace.split_uri(unicode(vee))
+        (ns, ln) = rdflib.namespace.split_uri(six.text_type(vee))
         name = ln
         if ns[0:-1] in namespaces:
-            vee = unicode(namespaces[ns[0:-1]][ln])
+            vee = six.text_type(namespaces[ns[0:-1]][ln])
         _logger.debug("name, v %s %s", name, vee)
 
     v = None  # type: Optional[Dict]
@@ -106,7 +108,7 @@ def process_type(t,             # type: Dict[str, Any]
         predicate = recordname
         if t.get("inVocab", True):
             if split.scheme:
-                (ns, ln) = rdflib.namespace.split_uri(unicode(recordname))
+                (ns, ln) = rdflib.namespace.split_uri(six.text_type(recordname))
                 predicate = recordname
                 recordname = ln
             else:
@@ -131,13 +133,13 @@ def process_type(t,             # type: Dict[str, Any]
             v = pred(t, i, fieldname, context, defaultPrefix,
                     namespaces)  # type: Union[Dict[Any, Any], unicode, None]
 
-            if isinstance(v, basestring):
+            if isinstance(v, six.string_types):
                 v = v if v[0] != "@" else None
             elif v is not None:
                 v = v["_@id"] if v.get("_@id", "@")[0] != "@" else None
 
             if bool(v):
-                (ns, ln) = rdflib.namespace.split_uri(unicode(v))
+                (ns, ln) = rdflib.namespace.split_uri(six.text_type(v))
                 if ns[0:-1] in namespaces:
                     propnode = namespaces[ns[0:-1]][ln]
                 else:
@@ -211,7 +213,7 @@ def makerdf(workflow,       # type: Union[str, unicode]
     # type: (...) -> Graph
     prefixes = {}
     idfields = []
-    for k, v in ctx.iteritems():
+    for k, v in six.iteritems(ctx):
         if isinstance(v, dict):
             url = v["@id"]
         else:
@@ -242,7 +244,7 @@ def makerdf(workflow,       # type: Union[str, unicode]
     for sub, pred, obj in g.triples((None, URIRef("@id"), None)):
         g.remove((sub, pred, obj))
 
-    for k2, v2 in prefixes.iteritems():
+    for k2, v2 in six.iteritems(prefixes):
         g.namespace_manager.bind(k2, v2)
 
     return g

schema_salad/main.py

@@ -1,4 +1,5 @@
 from __future__ import print_function
+from __future__ import absolute_import
 import argparse
 import logging
 import sys
@@ -20,6 +21,7 @@
 from . import validate
 from .sourceline import strip_dup_lineno
 from .ref_resolver import Loader
+import six
 
 _logger = logging.getLogger("salad")
 
@@ -118,8 +120,8 @@ def main(argsl=None):  # type: (List[str]) -> int
     except (validate.ValidationException) as e:
         _logger.error("Schema `%s` failed link checking:\n%s",
                       args.schema, e, exc_info=(True if args.debug else False))
-        _logger.debug("Index is %s", metaschema_loader.idx.keys())
-        _logger.debug("Vocabulary is %s", metaschema_loader.vocab.keys())
+        _logger.debug("Index is %s", list(metaschema_loader.idx.keys()))
+        _logger.debug("Vocabulary is %s", list(metaschema_loader.vocab.keys()))
         return 1
     except (RuntimeError) as e:
         _logger.error("Schema `%s` read error:\n%s",
@@ -132,7 +134,7 @@ def main(argsl=None):  # type: (List[str]) -> int
         return 0
 
     if not args.document and args.print_index:
-        print(json.dumps(metaschema_loader.idx.keys(), indent=4))
+        print(json.dumps(list(metaschema_loader.idx.keys()), indent=4))
         return 0
 
     # Validate the schema document against the metaschema
@@ -210,7 +212,7 @@ def main(argsl=None):  # type: (List[str]) -> int
         document, doc_metadata = document_loader.resolve_ref(uri)
     except (validate.ValidationException, RuntimeError) as e:
         _logger.error("Document `%s` failed validation:\n%s",
-                      args.document, strip_dup_lineno(unicode(e)), exc_info=args.debug)
+                      args.document, strip_dup_lineno(six.text_type(e)), exc_info=args.debug)
         return 1
 
     # Optionally print the document after ref resolution
@@ -219,7 +221,7 @@ def main(argsl=None):  # type: (List[str]) -> int
         return 0
 
     if args.print_index:
-        print(json.dumps(document_loader.idx.keys(), indent=4))
+        print(json.dumps(list(document_loader.idx.keys()), indent=4))
         return 0
 
     # Validate the schema document against the metaschema

schema_salad/makedoc.py

@@ -1,3 +1,4 @@
+from __future__ import absolute_import
 import mistune
 from . import schema
 import json
@@ -12,6 +13,8 @@
 import re
 import argparse
 from typing import cast, Any, Dict, IO, List, Optional, Set, Text, Union
+import six
+from six.moves import range
 
 _logger = logging.getLogger("salad")
 
@@ -29,7 +32,7 @@ def has_types(items):  # type: (Any) -> List[basestring]
         for i in items:
             r.extend(has_types(i))
         return r
-    if isinstance(items, basestring):
+    if isinstance(items, six.string_types):
         return [items]
     return []