[refactor] Improve python3 compatibility

With this commit all tests on py34 tox environment
are collected.

23 files changed, 71 insertions, 65 deletions

diff --git a/client/src/leap/soledad/client/_crypto.py b/client/src/leap/soledad/client/_crypto.py
index f91084a4..f9a20285 100644
--- a/client/src/leap/soledad/client/_crypto.py
+++ b/client/src/leap/soledad/client/_crypto.py
@@ -30,7 +30,7 @@ import struct
 import time
 
 from io import BytesIO
-from itertools import imap
+from six.moves import map as imap
 from collections import namedtuple
 
 from twisted.internet import defer
@@ -43,7 +43,7 @@ from cryptography.hazmat.backends.multibackend import MultiBackend
 from cryptography.hazmat.backends.openssl.backend \
     import Backend as OpenSSLBackend
 
-from zope.interface import implements
+from zope.interface import implementer
 
 
 SECRET_LENGTH = 64
@@ -290,7 +290,7 @@ class BlobDecryptor(object):
                 magic, sch, meth, ts, iv, doc_id, rev, doc_size = unpacked_data
             else:
                 raise InvalidBlob("Unexpected preamble size %d", len(preamble))
-        except struct.error, e:
+        except struct.error as e:
             raise InvalidBlob(e)
 
         if magic != BLOB_SIGNATURE_MAGIC:
@@ -325,12 +325,12 @@ class BlobDecryptor(object):
         return d
 
 
+@implementer(interfaces.IConsumer)
 class AESWriter(object):
     """
     A Twisted's Consumer implementation that takes an input file descriptor and
     applies AES-256 cipher in GCM mode.
     """
-    implements(interfaces.IConsumer)
 
     def __init__(self, key, iv=None, _buffer=None, tag=None, mode=modes.GCM):
         if len(key) != 32:
diff --git a/client/src/leap/soledad/client/_secrets/storage.py b/client/src/leap/soledad/client/_secrets/storage.py
index 056c4322..6ea89900 100644
--- a/client/src/leap/soledad/client/_secrets/storage.py
+++ b/client/src/leap/soledad/client/_secrets/storage.py
@@ -16,7 +16,7 @@
 # along with this program. If not, see <http://www.gnu.org/licenses/>.
 
 import json
-import urlparse
+import six.moves.urllib.parse as urlparse
 
 from hashlib import sha256
 
diff --git a/client/src/leap/soledad/client/adbapi.py b/client/src/leap/soledad/client/adbapi.py
index a5328d2b..2bc146bd 100644
--- a/client/src/leap/soledad/client/adbapi.py
+++ b/client/src/leap/soledad/client/adbapi.py
@@ -26,14 +26,17 @@ from functools import partial
 from twisted.enterprise import adbapi
 from twisted.internet.defer import DeferredSemaphore
 from zope.proxy import ProxyBase, setProxiedObject
-from pysqlcipher import dbapi2
 
 from leap.soledad.common.log import getLogger
 from leap.soledad.common.errors import DatabaseAccessError
-
 from leap.soledad.client import sqlcipher as soledad_sqlcipher
 from leap.soledad.client.pragmas import set_init_pragmas
 
+if sys.version_info[0] < 3:
+    from pysqlcipher import dbapi2
+else:
+    from pysqlcipher3 import dbapi2
+
 
 logger = getLogger(__name__)
 
@@ -276,7 +279,7 @@ class U1DBConnectionPool(adbapi.ConnectionPool):
                 conn.rollback()
             except:
                 logger.error(None, "Rollback failed")
-            raise excType, excValue, excTraceback
+            raise excType(excValue, excTraceback)
 
     def finalClose(self):
         """
diff --git a/client/src/leap/soledad/client/api.py b/client/src/leap/soledad/client/api.py
index c8c3ce30..3b17f188 100644
--- a/client/src/leap/soledad/client/api.py
+++ b/client/src/leap/soledad/client/api.py
@@ -27,20 +27,19 @@ remote storage in the server side.
 """
 import binascii
 import errno
-import httplib
 import os
 import socket
 import ssl
 import uuid
-import urlparse
 
 from itertools import chain
-
-from StringIO import StringIO
+import six.moves.http_client as httplib
+import six.moves.urllib.parse as urlparse
+from six import StringIO
 from collections import defaultdict
 
 from twisted.internet import defer
-from zope.interface import implements
+from zope.interface import implementer
 
 from leap.common.config import get_path_prefix
 from leap.common.plugins import collect_plugins
@@ -79,6 +78,9 @@ Soledad client and server.
 SOLEDAD_CERT = None
 
 
+@implementer(soledad_interfaces.ILocalStorage,
+             soledad_interfaces.ISyncableStorage,
+             soledad_interfaces.ISecretsStorage)
 class Soledad(object):
     """
     Soledad provides encrypted data storage and sync.
@@ -111,9 +113,6 @@ class Soledad(object):
           there's indeed new data to be synchronized between local database
           replica and server's replica. --- not used right now.
     """
-    implements(soledad_interfaces.ILocalStorage,
-               soledad_interfaces.ISyncableStorage,
-               soledad_interfaces.ISecretsStorage)
 
     local_db_file_name = 'soledad.u1db'
     secrets_file_name = "soledad.json"
diff --git a/client/src/leap/soledad/client/http_target/api.py b/client/src/leap/soledad/client/http_target/api.py
index fc65c9bd..c68185c6 100644
--- a/client/src/leap/soledad/client/http_target/api.py
+++ b/client/src/leap/soledad/client/http_target/api.py
@@ -18,7 +18,7 @@ import os
 import json
 import base64
 
-from StringIO import StringIO
+from six import StringIO
 from uuid import uuid4
 
 from twisted.internet import defer
diff --git a/client/src/leap/soledad/client/http_target/fetch_protocol.py b/client/src/leap/soledad/client/http_target/fetch_protocol.py
index c7eabe2b..851eb3a1 100644
--- a/client/src/leap/soledad/client/http_target/fetch_protocol.py
+++ b/client/src/leap/soledad/client/http_target/fetch_protocol.py
@@ -16,7 +16,7 @@
 # along with this program. If not, see <http://www.gnu.org/licenses/>.
 import json
 from functools import partial
-from cStringIO import StringIO
+from six import StringIO
 from twisted.web._newclient import ResponseDone
 from leap.soledad.common.l2db import errors
 from leap.soledad.common.l2db.remote import utils
@@ -70,7 +70,7 @@ class DocStreamReceiver(ReadBodyProtocol):
                 self.dataBuffer = self.metadata
             else:
                 self.dataBuffer = self.finish()
-        except errors.BrokenSyncStream, e:
+        except errors.BrokenSyncStream as e:
             return self.deferred.errback(e)
         return ReadBodyProtocol.connectionLost(self, reason)
 
diff --git a/client/src/leap/soledad/client/http_target/send_protocol.py b/client/src/leap/soledad/client/http_target/send_protocol.py
index 0cb6d039..4941aa34 100644
--- a/client/src/leap/soledad/client/http_target/send_protocol.py
+++ b/client/src/leap/soledad/client/http_target/send_protocol.py
@@ -14,20 +14,19 @@
 #
 # You should have received a copy of the GNU General Public License
 # along with this program. If not, see <http://www.gnu.org/licenses/>.
-from zope.interface import implements
+from zope.interface import implementer
 from twisted.internet import defer
 from twisted.internet import reactor
 from twisted.web.iweb import IBodyProducer
 from twisted.web.iweb import UNKNOWN_LENGTH
 
 
+@implementer(IBodyProducer)
 class DocStreamProducer(object):
     """
     A producer that writes the body of a request to a consumer.
     """
 
-    implements(IBodyProducer)
-
     def __init__(self, producer):
         """
         Initialize the string produer.
diff --git a/client/src/leap/soledad/client/sqlcipher.py b/client/src/leap/soledad/client/sqlcipher.py
index a3e45228..2c995d5a 100644
--- a/client/src/leap/soledad/client/sqlcipher.py
+++ b/client/src/leap/soledad/client/sqlcipher.py
@@ -42,11 +42,10 @@ SQLCipher 1.1 databases, we do not implement them as all SQLCipher databases
 handled by Soledad should be created by SQLCipher >= 2.0.
 """
 import os
+import sys
 
 from functools import partial
 
-from pysqlcipher import dbapi2 as sqlcipher_dbapi2
-
 from twisted.internet import reactor
 from twisted.internet import defer
 from twisted.enterprise import adbapi
@@ -62,6 +61,10 @@ from leap.soledad.client.http_target import SoledadHTTPSyncTarget
 from leap.soledad.client.sync import SoledadSynchronizer
 from leap.soledad.client import pragmas
 
+if sys.version_info[0] < 3:
+    from pysqlcipher import dbapi2 as sqlcipher_dbapi2
+else:
+    from pysqlcipher3 import dbapi2 as sqlcipher_dbapi2
 
 logger = getLogger(__name__)
 
@@ -306,7 +309,7 @@ class SQLCipherDatabase(sqlite_backend.SQLitePartialExpandDatabase):
             ))
         try:
             c.execute(statement, tuple(args))
-        except sqlcipher_dbapi2.OperationalError, e:
+        except sqlcipher_dbapi2.OperationalError as e:
             raise sqlcipher_dbapi2.OperationalError(
                 str(e) + '\nstatement: %s\nargs: %s\n' % (statement, args))
         res = c.fetchall()
diff --git a/common/src/leap/soledad/common/command.py b/common/src/leap/soledad/common/command.py
index 811bf135..66aa6b7a 100644
--- a/common/src/leap/soledad/common/command.py
+++ b/common/src/leap/soledad/common/command.py
@@ -45,7 +45,7 @@ def exec_validated_cmd(cmd, argument, validator=None):
     try:
         process = subprocess.Popen(command, stdout=subprocess.PIPE,
                                    stderr=subprocess.PIPE)
-    except OSError, e:
+    except OSError as e:
         return 1, e
     (out, err) = process.communicate()
     code = process.wait()
diff --git a/common/src/leap/soledad/common/couch/__init__.py b/common/src/leap/soledad/common/couch/__init__.py
index 2e6f734e..2343e849 100644
--- a/common/src/leap/soledad/common/couch/__init__.py
+++ b/common/src/leap/soledad/common/couch/__init__.py
@@ -25,9 +25,8 @@ import re
 import uuid
 import binascii
 
-
-from StringIO import StringIO
-from urlparse import urljoin
+from six import StringIO
+from six.moves.urllib.parse import urljoin
 from contextlib import contextmanager
 
 
diff --git a/common/src/leap/soledad/common/couch/state.py b/common/src/leap/soledad/common/couch/state.py
index a4841d0d..8cbe0934 100644
--- a/common/src/leap/soledad/common/couch/state.py
+++ b/common/src/leap/soledad/common/couch/state.py
@@ -19,7 +19,8 @@ Server state using CouchDatabase as backend.
 """
 import couchdb
 import re
-from urlparse import urljoin
+
+from six.moves.urllib.parse import urljoin
 
 from leap.soledad.common.log import getLogger
 from leap.soledad.common.couch import CouchDatabase
diff --git a/common/src/leap/soledad/common/l2db/backends/sqlite_backend.py b/common/src/leap/soledad/common/l2db/backends/sqlite_backend.py
index 27db65af..4f7b1259 100644
--- a/common/src/leap/soledad/common/l2db/backends/sqlite_backend.py
+++ b/common/src/leap/soledad/common/l2db/backends/sqlite_backend.py
@@ -58,7 +58,7 @@ class SQLiteDatabase(CommonBackend):
         try:
             c.execute("SELECT value FROM u1db_config"
                       " WHERE name = 'index_storage'")
-        except dbapi2.OperationalError, e:
+        except dbapi2.OperationalError as e:
             # The table does not exist yet
             return None, e
         else:
@@ -668,7 +668,7 @@ class SQLiteDatabase(CommonBackend):
         c = self._db_handle.cursor()
         try:
             c.execute(statement, tuple(args))
-        except dbapi2.OperationalError, e:
+        except dbapi2.OperationalError as e:
             raise dbapi2.OperationalError(
                 str(e) +
                 '\nstatement: %s\nargs: %s\n' % (statement, args))
@@ -768,7 +768,7 @@ class SQLiteDatabase(CommonBackend):
         c = self._db_handle.cursor()
         try:
             c.execute(statement, tuple(args))
-        except dbapi2.OperationalError, e:
+        except dbapi2.OperationalError as e:
             raise dbapi2.OperationalError(
                 str(e) +
                 '\nstatement: %s\nargs: %s\n' % (statement, args))
@@ -798,7 +798,7 @@ class SQLiteDatabase(CommonBackend):
                 value_fields))
         try:
             c.execute(statement, tuple(definition))
-        except dbapi2.OperationalError, e:
+        except dbapi2.OperationalError as e:
             raise dbapi2.OperationalError(
                 str(e) +
                 '\nstatement: %s\nargs: %s\n' % (statement, tuple(definition)))
@@ -893,7 +893,10 @@ class SQLitePartialExpandDatabase(SQLiteDatabase):
                 stored_def = self._get_index_definition(index_name)
                 if stored_def == [x[-1] for x in definition]:
                     return
-                raise errors.IndexNameTakenError, e, sys.exc_info()[2]
+                raise errors.IndexNameTakenError(
+                    str(e) +
+                    str(sys.exc_info()[2])
+                )
             new_fields = set(
                 [f for f in index_expressions if f not in cur_fields])
             if new_fields:
diff --git a/common/src/leap/soledad/common/l2db/query_parser.py b/common/src/leap/soledad/common/l2db/query_parser.py
index dd35b12a..15a9ac80 100644
--- a/common/src/leap/soledad/common/l2db/query_parser.py
+++ b/common/src/leap/soledad/common/l2db/query_parser.py
@@ -323,7 +323,7 @@ class Parser(object):
             else:
                 try:
                     inner = arg_type(arg)
-                except ValueError, e:
+                except ValueError as e:
                     raise errors.IndexDefinitionParseError(
                         "Invalid value %r for argument type %r "
                         "(%r)." % (arg, arg_type, e))
diff --git a/common/src/leap/soledad/common/l2db/remote/http_app.py b/common/src/leap/soledad/common/l2db/remote/http_app.py
index 496274b2..a4eddb36 100644
--- a/common/src/leap/soledad/common/l2db/remote/http_app.py
+++ b/common/src/leap/soledad/common/l2db/remote/http_app.py
@@ -21,11 +21,11 @@ HTTP Application exposing U1DB.
 # TODO -- deprecate, use twisted/txaio.
 
 import functools
-import httplib
+import six.moves.http_client as httplib
 import inspect
 import json
 import sys
-import urlparse
+import six.moves.urllib.parse as urlparse
 
 import routes.mapper
 
@@ -610,7 +610,7 @@ class HTTPApp(object):
         try:
             resource = self._lookup_resource(environ, responder)
             HTTPInvocationByMethodWithBody(resource, environ, self)()
-        except errors.U1DBError, e:
+        except errors.U1DBError as e:
             self.request_u1db_error(environ, e)
             status = http_errors.wire_description_to_status.get(
                 e.wire_description, 500)
diff --git a/common/src/leap/soledad/common/l2db/remote/http_client.py b/common/src/leap/soledad/common/l2db/remote/http_client.py
index 53363c0a..1124b038 100644
--- a/common/src/leap/soledad/common/l2db/remote/http_client.py
+++ b/common/src/leap/soledad/common/l2db/remote/http_client.py
@@ -16,14 +16,13 @@
 
 """Base class to make requests to a remote HTTP server."""
 
-import httplib
 import json
 import socket
 import ssl
 import sys
-import urlparse
 import urllib
-
+import six.moves.urllib.parse as urlparse
+import six.moves.http_client as httplib
 from time import sleep
 from leap.soledad.common.l2db import errors
 from leap.soledad.common.l2db.remote import http_errors
@@ -168,7 +167,7 @@ class HTTPClientBase(object):
             try:
                 self._conn.request(method, url_query, body, headers)
                 return self._response()
-            except errors.Unavailable, e:
+            except errors.Unavailable as e:
                 sleep(delay)
         raise e
 
diff --git a/common/src/leap/soledad/common/l2db/remote/http_database.py b/common/src/leap/soledad/common/l2db/remote/http_database.py
index 7512379f..7e61e5a4 100644
--- a/common/src/leap/soledad/common/l2db/remote/http_database.py
+++ b/common/src/leap/soledad/common/l2db/remote/http_database.py
@@ -87,7 +87,7 @@ class HTTPDatabase(http_client.HTTPClientBase, Database):
                 'GET', ['doc', doc_id], {"include_deleted": include_deleted})
         except errors.DocumentDoesNotExist:
             return None
-        except errors.HTTPError, e:
+        except errors.HTTPError as e:
             if (e.status == DOCUMENT_DELETED_STATUS and
                     'x-u1db-rev' in e.headers):
                         res = None
diff --git a/common/src/leap/soledad/common/l2db/sync.py b/common/src/leap/soledad/common/l2db/sync.py
index 5e9b22f4..32281f30 100644
--- a/common/src/leap/soledad/common/l2db/sync.py
+++ b/common/src/leap/soledad/common/l2db/sync.py
@@ -15,7 +15,7 @@
 # along with u1db.  If not, see <http://www.gnu.org/licenses/>.
 
 """The synchronization utilities for U1DB."""
-from itertools import izip
+from six.moves import zip as izip
 
 from leap.soledad.common import l2db
 from leap.soledad.common.l2db import errors
diff --git a/server/src/leap/soledad/server/__init__.py b/server/src/leap/soledad/server/__init__.py
index 5bed22c9..6640bab4 100644
--- a/server/src/leap/soledad/server/__init__.py
+++ b/server/src/leap/soledad/server/__init__.py
@@ -82,7 +82,7 @@ documents on the shared database is handled by `leap.soledad.server.auth`
 module.
 """
 
-import urlparse
+import six.moves.urllib.parse as urlparse
 import sys
 
 from leap.soledad.common.l2db.remote import http_app, utils
diff --git a/server/src/leap/soledad/server/gzip_middleware.py b/server/src/leap/soledad/server/gzip_middleware.py
index 986c5738..c77f9f67 100644
--- a/server/src/leap/soledad/server/gzip_middleware.py
+++ b/server/src/leap/soledad/server/gzip_middleware.py
@@ -17,7 +17,7 @@
 """
 Gzip middleware for WSGI apps.
 """
-import StringIO
+from six import StringIO
 from gzip import GzipFile
 
 
diff --git a/server/src/leap/soledad/server/sync.py b/server/src/leap/soledad/server/sync.py
index b553a056..6791c06c 100644
--- a/server/src/leap/soledad/server/sync.py
+++ b/server/src/leap/soledad/server/sync.py
@@ -18,7 +18,7 @@
 Server side synchronization infrastructure.
 """
 import time
-from itertools import izip
+from six.moves import zip as izip
 
 from leap.soledad.common.l2db import sync
 from leap.soledad.common.l2db.remote import http_app
diff --git a/testing/test_soledad/u1db_tests/__init__.py b/testing/test_soledad/u1db_tests/__init__.py
index 36db548d..1575b859 100644
--- a/testing/test_soledad/u1db_tests/__init__.py
+++ b/testing/test_soledad/u1db_tests/__init__.py
@@ -28,12 +28,6 @@ import sys
 from six import StringIO
 from wsgiref import simple_server
 
-
-if sys.version_info[0] < 3:
-    from pysqlcipher import dbapi2
-else:
-    from pysqlcipher3 import dbapi2
-
 import testscenarios
 from twisted.trial import unittest
 from twisted.web.server import Site
@@ -48,6 +42,11 @@ from leap.soledad.common.l2db.remote import server_state
 from leap.soledad.common.l2db.remote import http_app
 from leap.soledad.common.l2db.remote import http_target
 
+if sys.version_info[0] < 3:
+    from pysqlcipher import dbapi2
+else:
+    from pysqlcipher3 import dbapi2
+
 
 class TestCase(unittest.TestCase):
 
diff --git a/testing/test_soledad/util.py b/testing/test_soledad/util.py
index 91291faf..6ffb60b6 100644
--- a/testing/test_soledad/util.py
+++ b/testing/test_soledad/util.py
@@ -31,11 +31,6 @@ from six import StringIO
 from uuid import uuid4
 from mock import Mock
 
-if sys.version_info[0] < 3:
-    from pysqlcipher import dbapi2
-else:
-    from pysqlcipher3 import dbapi2
-
 from twisted.trial import unittest
 
 from leap.common.testing.basetest import BaseLeapTest
@@ -48,7 +43,6 @@ from leap.soledad.common.document import SoledadDocument
 from leap.soledad.common.couch import CouchDatabase
 from leap.soledad.common.couch.state import CouchServerState
 
-
 from leap.soledad.client import Soledad
 from leap.soledad.client import http_target
 from leap.soledad.client import auth
@@ -58,6 +52,11 @@ from leap.soledad.client._crypto import is_symmetrically_encrypted
 
 from leap.soledad.server import SoledadApp
 
+if sys.version_info[0] < 3:
+    from pysqlcipher import dbapi2
+else:
+    from pysqlcipher3 import dbapi2
+
 
 PASSWORD = '123456'
 ADDRESS = 'user-1234'
diff --git a/testing/tests/sqlcipher/test_backend.py b/testing/tests/sqlcipher/test_backend.py
index 643fa041..6e9595db 100644
--- a/testing/tests/sqlcipher/test_backend.py
+++ b/testing/tests/sqlcipher/test_backend.py
@@ -22,11 +22,6 @@ import pytest
 import time
 import threading
 import sys
-if sys.version_info[0] < 3:
-    from pysqlcipher import dbapi2
-else:
-    from pysqlcipher3 import dbapi2
-from testscenarios import TestWithScenarios
 
 # l2db stuff.
 from leap.soledad.common.l2db import errors
@@ -48,6 +43,13 @@ from test_soledad.util import SQLCIPHER_SCENARIOS
 from test_soledad.util import PASSWORD
 from test_soledad.util import BaseSoledadTest
 
+from testscenarios import TestWithScenarios
+
+if sys.version_info[0] < 3:
+    from pysqlcipher import dbapi2
+else:
+    from pysqlcipher3 import dbapi2
+
 
 def sqlcipher_open(path, passphrase, create=True, document_factory=None):
     return SQLCipherDatabase(