Fix Py3.7 warnings (#767)

dist: xenial   # required for Python >= 3.7
see https://docs.travis-ci.com/user/languages/python/

Author: pschelle

.travis.yml

@@ -1,10 +1,12 @@
+dist: xenial   # required for Python >= 3.7
 language: python
 
 python:
 - '2.7'
 - '3.4'
 - '3.5'
 - '3.6'
+- '3.7'
 
 os:
 - linux

minio/copy_conditions.py

@@ -25,6 +25,10 @@
 """
 
 import collections
+try:
+    collectionsAbc = collections.abc
+except AttributeError:
+    collectionsAbc = collections
 from .helpers import is_non_empty_string
 
 # CopyCondition explanation:
@@ -36,7 +40,7 @@
 #      key: "x-amz-copy-if-modified-since",
 #      value: "Tue, 15 Nov 1994 12:45:26 GMT",
 #
-class CopyConditions(collections.MutableMapping):
+class CopyConditions(collectionsAbc.MutableMapping):
     """
     A :class:`CopyConditions <CopyConditions>` collection of
        supported CopyObject conditions.

minio/helpers.py

@@ -53,7 +53,7 @@
 
 _VALID_BUCKETNAME_REGEX = re.compile('^[a-z0-9][a-z0-9\\.\\-]+[a-z0-9]$')
 _ALLOWED_HOSTNAME_REGEX = re.compile(
-    '^((?!-)(?!_)[A-Z\_\\d-]{1,63}(?<!-)(?<!_)\\.)*((?!_)(?!-)[A-Z\_\\d-]{1,63}(?<!-)(?<!_))$',
+    '^((?!-)(?!_)[A-Z_\\d-]{1,63}(?<!-)(?<!_)\\.)*((?!_)(?!-)[A-Z_\\d-]{1,63}(?<!-)(?<!_))$',
     re.IGNORECASE)
 
 _EXTRACT_REGION_REGEX = re.compile('s3[.-]?(.+?).amazonaws.com')

setup.py

@@ -77,6 +77,7 @@
         'Programming Language :: Python :: 3.4',
         'Programming Language :: Python :: 3.5',
         'Programming Language :: Python :: 3.6',
+        'Programming Language :: Python :: 3.7',
         'Topic :: Software Development :: Libraries :: Python Modules',
     ],
     long_description=readme,