Update code to be Python3 compatible

client/docker_creds_.py

@@ -13,11 +13,15 @@
 # limitations under the License.
 """This package exposes credentials for talking to a Docker registry."""
 
+from __future__ import absolute_import
+from __future__ import division
 
+from __future__ import print_function
 
 import abc
 import base64
 import errno
+import io
 import json
 import logging
 import os
@@ -27,11 +31,11 @@
 import httplib2
 from oauth2client import client as oauth2client
 
+import six
 
-class Provider(object):
-  """Interface for providing User Credentials for use with a Docker Registry."""
 
-  __metaclass__ = abc.ABCMeta  # For enforcing that methods are overridden.
+class Provider(six.with_metaclass(abc.ABCMeta, object)):
+  """Interface for providing User Credentials for use with a Docker Registry."""
 
   # pytype: disable=bad-return-type
   @abc.abstractmethod
@@ -63,7 +67,7 @@ def suffix(self):
 
   def Get(self):
     """Gets the credential in a form suitable for an Authorization header."""
-    return '%s %s' % (self._scheme, self.suffix)
+    return u'%s %s' % (self._scheme, self.suffix)
 
 
 class Basic(SchemeProvider):
@@ -84,7 +88,9 @@ def password(self):
 
   @property
   def suffix(self):
-    return base64.b64encode(self.username + ':' + self.password)
+    u = self.username.encode('utf8')
+    p = self.password.encode('utf8')
+    return base64.b64encode(u + b':' + p).decode('utf8')
 
 
 _USERNAME = '_token'
@@ -159,9 +165,7 @@ def Get(self):
     # Some keychains expect a scheme:
     # https://github.com/bazelbuild/rules_docker/issues/111
     stdout = p.communicate(input='https://' + self._registry)[0]
-
-    output = stdout.decode()
-    if output.strip() == _MAGIC_NOT_FOUND_MESSAGE:
+    if stdout.strip() == _MAGIC_NOT_FOUND_MESSAGE:
       # Use empty auth when no auth is found.
       logging.info('Credentials not found, falling back to anonymous auth.')
       return Anonymous().Get()
@@ -170,16 +174,14 @@ def Get(self):
       raise Exception('Error fetching credential for %s, exit status: %d\n%s' %
                       (self._name, p.returncode, stdout))
 
-    blob = json.loads(output)
+    blob = json.loads(stdout)
     logging.info('Successfully obtained Docker credentials.')
     return Basic(blob['Username'], blob['Secret']).Get()
 
 
-class Keychain(object):
+class Keychain(six.with_metaclass(abc.ABCMeta, object)):
   """Interface for resolving an image reference to a credential."""
 
-  __metaclass__ = abc.ABCMeta  # For enforcing that methods are overridden.
-
   # pytype: disable=bad-return-type
   @abc.abstractmethod
   def Resolve(self, name):
@@ -235,7 +237,7 @@ def Resolve(self, name):
     logging.info('Loading Docker credentials for repository %r', str(name))
     config_file = os.path.join(_GetConfigDirectory(), 'config.json')
     try:
-      with open(config_file, 'r') as reader:
+      with io.open(config_file, u'r', encoding='utf8') as reader:
         cfg = json.loads(reader.read())
     except IOError:
       # If the file doesn't exist, fallback on anonymous auth.
@@ -257,7 +259,8 @@ def Resolve(self, name):
       if form % name.registry in auths:
         entry = auths[form % name.registry]
         if 'auth' in entry:
-          username, password = base64.b64decode(entry['auth']).split(':', 1)
+          decoded = base64.b64decode(entry['auth']).decode('utf8')
+          username, password = decoded.split(':', 1)
           return Basic(username, password)
         elif 'username' in entry and 'password' in entry:
           return Basic(entry['username'], entry['password'])

client/docker_name_.py

@@ -13,11 +13,14 @@
 # limitations under the License.
 """This package defines Tag a way of representing an image uri."""
 
+from __future__ import absolute_import
+from __future__ import division
 
+from __future__ import print_function
 
 import os
 import sys
-import urlparse
+import six.moves.urllib.parse
 
 
 
@@ -39,13 +42,8 @@ class BadNameException(Exception):
 DEFAULT_TAG = 'latest'
 
 
-def _check_element(
-    name,
-    element,
-    characters,
-    min_len,
-    max_len
-):
+def _check_element(name, element, characters, min_len,
+                   max_len):
   """Checks a given named element matches character and length restrictions.
 
   Args:
@@ -86,7 +84,7 @@ def _check_digest(digest):
 
 def _check_registry(registry):
   # Per RFC 3986, netlocs (authorities) are required to be prefixed with '//'
-  parsed_hostname = urlparse.urlparse('//' + registry)
+  parsed_hostname = six.moves.urllib.parse.urlparse('//' + registry)
 
   # If urlparse doesn't recognize the given registry as a netloc, fail
   # validation.

client/monitor_.py

@@ -13,20 +13,22 @@
 # limitations under the License.
 """This module contains utilities for monitoring client side calls."""
 
+from __future__ import absolute_import
+from __future__ import division
 
+from __future__ import print_function
 
 import abc
+import six
 
 
 
-class Context(object):
+class Context(six.with_metaclass(abc.ABCMeta, object)):
   """Interface for implementations of client monitoring context manager.
 
   All client operations are executed inside this context.
   """
 
-  __metaclass__ = abc.ABCMeta  # For enforcing that methods are overridden.
-
   @abc.abstractmethod
   def __init__(self, operation):
     pass
@@ -46,6 +48,7 @@ def __exit__(self, exc_type,
 class Nop(Context):
   """Default implementation of Context that does nothing."""
 
+  # pylint: disable=useless-super-delegation
   def __init__(self, operation):
     super(Nop, self).__init__(operation)
 

client/v1/docker_creds_.py

@@ -13,7 +13,10 @@
 # limitations under the License.
 """This package exposes credentials for talking to a Docker registry."""
 
+from __future__ import absolute_import
+from __future__ import division
 
+from __future__ import print_function
 
 from containerregistry.client import docker_creds
 

client/v1/docker_http_.py

@@ -13,7 +13,10 @@
 # limitations under the License.
 """This package facilitates HTTP/REST requests to the registry."""
 
+from __future__ import absolute_import
+from __future__ import division
 
+from __future__ import print_function
 
 from containerregistry.client import docker_creds
 from containerregistry.client import docker_name