[Fix #201] Removing old elasticsearc compatibility (#219)

* Removing old elasticsearc compatibility

* Fixing import

Author: safwanrahman

django_elasticsearch_dsl/fields.py

@@ -1,13 +1,11 @@
 import collections
 from types import MethodType
-import warnings
 
 from django.core.exceptions import ObjectDoesNotExist
 from django.db import models
 from django.db.models.fields.files import FieldFile
 from django.utils.encoding import force_text
 from django.utils.functional import Promise
-
 from elasticsearch_dsl.field import (
     Boolean,
     Byte,
@@ -24,7 +22,10 @@
     Nested,
     Object,
     Short,
+    Keyword,
+    Text
 )
+
 from .exceptions import VariableLookupError
 
 
@@ -210,61 +211,13 @@ def get_value_from_instance(self, instance, field_value_to_ignore=None):
         return _file if _file else ''
 
 
-# ES5+ has text types Keyword and Text, ES2 has type String.
-try:
-    from elasticsearch_dsl.field import Keyword, Text
-
-    class KeywordField(DEDField, Keyword):
-        pass
-
-    class TextField(DEDField, Text):
-        pass
-
-    class StringField(DEDField, Text):
-        warnings.warn(
-            'StringField is deprecated in Elasticsearch 5 and removed in '
-            'Elasticsearch 6. Please use TextField and KeywordField instead.',
-            DeprecationWarning
-        )
-
-    class FileField(FileFieldMixin, DEDField, Text):
-        pass
-
-
-except ImportError:
-    from elasticsearch_dsl.field import String
-
-    class KeywordField(DEDField, String):
-        def __init__(self, **kwargs):
-            if 'index' not in kwargs or kwargs['index'] is True:
-                # Unless a custom 'index' setting was provided, create the
-                # Keyword field as a "not_analyzed" field.
-                kwargs['index'] = 'not_analyzed'
-            super(KeywordField, self).__init__(**kwargs)
-
-    class TextField(DEDField, String):
-        pass
-
-    class StringField(DEDField, String):
-        pass
-
-    class FileField(FileFieldMixin, DEDField, String):
-        pass
+class KeywordField(DEDField, Keyword):
+    pass
 
 
-# Elasticsearch 2 and 5 have an Attachment field, ES 6 doesn't.
-try:
-    from elasticsearch_dsl.field import Attachment
+class TextField(DEDField, Text):
+    pass
 
-    class AttachmentField(DEDField, Attachment):
-        pass
-except ImportError:
-    from elasticsearch_dsl.field import Text
 
-    class AttachmentField(DEDField, Text):
-        name = 'attachment'
-        warnings.warn(
-            'AttachmentField is deprecated in Elasticsearch 5 and removed in '
-            'Elasticsearch 6.',
-            DeprecationWarning
-        )
+class FileField(FileFieldMixin, DEDField, Text):
+    pass