launchpad-reviewers team mailing list archive

[Colin Watson <cjwatson@xxxxxxxxxxxxx>]

Colin Watson has proposed merging ~cjwatson/launchpad:py3-backports into launchpad:master.

Commit message:
Limit some external packages by Python version

Requested reviews:
  Launchpad code reviewers (launchpad-reviewers)

For more details, see:
https://code.launchpad.net/~cjwatson/launchpad/+git/launchpad/+merge/378459

backports.lzma, contextlib2, and ipaddress are all backports of standard library additions in Python 3.3, so restrict these to Python < 3.3 and adjust imports where appropriate.  Likewise, importlib-resources is a backport of a standard library addition in Python 3.7.

In principle we could apply the same treatment to scandir, which was added to the standard library in 3.5, but the import adjustments get pretty verbose.  It's probably easiest to just drop this once we're on >= 3.5 everywhere.
-- 
Your team Launchpad code reviewers is requested to review the proposed merge of ~cjwatson/launchpad:py3-backports into launchpad:master.

diff --git a/lib/lp/code/model/branchmergeproposaljob.py b/lib/lp/code/model/branchmergeproposaljob.py
index cc6b20c..d6cd0ec 100644
--- a/lib/lp/code/model/branchmergeproposaljob.py
+++ b/lib/lp/code/model/branchmergeproposaljob.py
@@ -21,13 +21,15 @@ __all__ = [
     'UpdatePreviewDiffJob',
     ]
 
-from contextlib import contextmanager
+try:
+    from contextlib import ExitStack
+except ImportError:
+    from contextlib2 import ExitStack
 from datetime import (
     datetime,
     timedelta,
     )
 
-from contextlib2 import ExitStack
 from lazr.delegates import delegate_to
 from lazr.enum import (
     DBEnumeratedType,
diff --git a/lib/lp/code/model/diff.py b/lib/lp/code/model/diff.py
index b5a0cb1..d74c103 100644
--- a/lib/lp/code/model/diff.py
+++ b/lib/lp/code/model/diff.py
@@ -10,6 +10,10 @@ __all__ = [
     'PreviewDiff',
     ]
 
+try:
+    from contextlib import ExitStack
+except ImportError:
+    from contextlib2 import ExitStack
 from cStringIO import StringIO
 from operator import attrgetter
 import sys
@@ -23,7 +27,6 @@ from breezy.patches import (
     Patch,
     )
 from breezy.plugins.difftacular.generate_diff import diff_ignore_branches
-from contextlib2 import ExitStack
 from lazr.delegates import delegate_to
 import simplejson
 from sqlobject import (
diff --git a/lib/lp/scripts/runlaunchpad.py b/lib/lp/scripts/runlaunchpad.py
index daa6471..11e06e4 100644
--- a/lib/lp/scripts/runlaunchpad.py
+++ b/lib/lp/scripts/runlaunchpad.py
@@ -6,13 +6,15 @@ from __future__ import absolute_import, print_function, unicode_literals
 __metaclass__ = type
 __all__ = ['start_launchpad']
 
-
+try:
+    from contextlib import ExitStack
+except ImportError:
+    from contextlib2 import ExitStack
 import os
 import signal
 import subprocess
 import sys
 
-from contextlib2 import ExitStack
 import fixtures
 from lazr.config import as_host_port
 from rabbitfixture.server import RabbitServerResources
diff --git a/lib/lp/services/config/__init__.py b/lib/lp/services/config/__init__.py
index a223fc6..80b1d0c 100644
--- a/lib/lp/services/config/__init__.py
+++ b/lib/lp/services/config/__init__.py
@@ -12,6 +12,10 @@ __metaclass__ = type
 
 
 import glob
+try:
+    from importlib import resources
+except ImportError:
+    import importlib_resources as resources
 import logging
 import os
 import sys
@@ -20,7 +24,6 @@ from urlparse import (
     urlunparse,
     )
 
-import importlib_resources
 from lazr.config import ImplicitTypeSchema
 from lazr.config.interfaces import ConfigErrors
 import ZConfig
@@ -241,8 +244,7 @@ class LaunchpadConfig:
 
     def _setZConfig(self):
         """Modify the config, adding automatically generated settings"""
-        with importlib_resources.path(
-                'zope.app.server', 'schema.xml') as schemafile:
+        with resources.path('zope.app.server', 'schema.xml') as schemafile:
             schema = ZConfig.loadSchema(str(schemafile))
         root_options, handlers = ZConfig.loadConfig(
             schema, self.zope_config_file)
diff --git a/lib/lp/services/config/tests/test_config.py b/lib/lp/services/config/tests/test_config.py
index 44928e4..e219ab0 100644
--- a/lib/lp/services/config/tests/test_config.py
+++ b/lib/lp/services/config/tests/test_config.py
@@ -12,11 +12,14 @@ from doctest import (
     ELLIPSIS,
     NORMALIZE_WHITESPACE,
     )
+try:
+    from importlib import resources
+except ImportError:
+    import importlib_resources as resources
 import os
 import unittest
 
 from fixtures import TempDir
-import importlib_resources
 from lazr.config import ConfigSchema
 from lazr.config.interfaces import ConfigErrors
 import scandir
@@ -30,7 +33,7 @@ from lp.services.config.fixture import ConfigUseFixture
 EXCLUDED_CONFIGS = ['lpnet-template']
 
 # Calculate some landmark paths.
-with importlib_resources.path('zope.app.server', 'schema.xml') as schema_file:
+with resources.path('zope.app.server', 'schema.xml') as schema_file:
     schema = ZConfig.loadSchema(str(schema_file))
 
 here = os.path.dirname(lp.services.config.__file__)
diff --git a/lib/lp/services/webservice/wadl.py b/lib/lp/services/webservice/wadl.py
index eb70668..f11e2e1 100644
--- a/lib/lp/services/webservice/wadl.py
+++ b/lib/lp/services/webservice/wadl.py
@@ -5,11 +5,13 @@
 
 __metaclass__ = type
 
+try:
+    from importlib import resources
+except ImportError:
+    import importlib_resources as resources
 import subprocess
 import urlparse
 
-import importlib_resources
-
 from lp.services.webapp.interaction import (
     ANONYMOUS,
     setupInteractionByEmail,
@@ -57,7 +59,7 @@ def generate_html(wadl_filename, suppress_stderr=True):
     # stderr (like we want to do during test runs), we reassign the subprocess
     # stderr file handle and then discard the output.  Otherwise we let the
     # subprocess inherit stderr.
-    with importlib_resources.path(
+    with resources.path(
             'lp.services.webservice', 'wadl-to-refhtml.xsl') as stylesheet:
         if suppress_stderr:
             stderr = subprocess.PIPE
diff --git a/setup.py b/setup.py
index 0ab1ce4..8f97448 100644
--- a/setup.py
+++ b/setup.py
@@ -146,12 +146,12 @@ setup(
         'ampoule',
         'auditorclient',
         'auditorfixture',
-        'backports.lzma',
+        'backports.lzma; python_version < "3.3"',
         'beautifulsoup4[lxml]',
         'breezy',
         'bzr',
         'celery',
-        'contextlib2',
+        'contextlib2; python_version < "3.3"',
         'cssselect',
         'cssutils',
         'defusedxml',
@@ -164,8 +164,8 @@ setup(
         'fixtures',
         'geoip2',
         'gunicorn[gthread]',
-        'importlib-resources',
-        'ipaddress',
+        'importlib-resources; python_version < "3.7"',
+        'ipaddress; python_version < "3.3"',
         'ipython',
         'jsautobuild',
         'launchpad-buildd',