cc_apt_pipelining: stop disabling pipelining by default

This was introduced due to Ubuntu using S3 mirrors, and S3 having a
buggy pipelining implementation.  Those Ubuntu mirrors are no longer in
production and, furthremore, apt has also grown the ability to handle
servers with broken pipelining.

As such, we can stop disabling pipelining, which should result in
improved apt download speeds.

LP: #1794982

2 files changed, 30 insertions, 2 deletions

diff --git a/cloudinit/config/cc_apt_pipelining.py b/cloudinit/config/cc_apt_pipelining.py
index cdf28cd9..459332ab 100644
--- a/cloudinit/config/cc_apt_pipelining.py
+++ b/cloudinit/config/cc_apt_pipelining.py
@@ -49,7 +49,7 @@ APT_PIPE_TPL = ("//Written by cloud-init per 'apt_pipelining'\n"
 
 def handle(_name, cfg, _cloud, log, _args):
 
-    apt_pipe_value = util.get_cfg_option_str(cfg, "apt_pipelining", False)
+    apt_pipe_value = util.get_cfg_option_str(cfg, "apt_pipelining", 'os')
     apt_pipe_value_s = str(apt_pipe_value).lower().strip()
 
     if apt_pipe_value_s == "false":
@@ -59,7 +59,7 @@ def handle(_name, cfg, _cloud, log, _args):
     elif apt_pipe_value_s in [str(b) for b in range(0, 6)]:
         write_apt_snippet(apt_pipe_value_s, log, DEFAULT_FILE)
     else:
-        log.warn("Invalid option for apt_pipeling: %s", apt_pipe_value)
+        log.warn("Invalid option for apt_pipelining: %s", apt_pipe_value)
 
 
 def write_apt_snippet(setting, log, f_name):
diff --git a/cloudinit/config/tests/test_apt_pipelining.py b/cloudinit/config/tests/test_apt_pipelining.py
new file mode 100644
index 00000000..2a6bb10b
--- /dev/null
+++ b/cloudinit/config/tests/test_apt_pipelining.py
@@ -0,0 +1,28 @@
+# This file is part of cloud-init. See LICENSE file for license information.
+
+"""Tests cc_apt_pipelining handler"""
+
+import cloudinit.config.cc_apt_pipelining as cc_apt_pipelining
+
+from cloudinit.tests.helpers import CiTestCase, mock
+
+
+class TestAptPipelining(CiTestCase):
+
+    @mock.patch('cloudinit.config.cc_apt_pipelining.util.write_file')
+    def test_not_disabled_by_default(self, m_write_file):
+        """ensure that default behaviour is to not disable pipelining"""
+        cc_apt_pipelining.handle('foo', {}, None, mock.MagicMock(), None)
+        self.assertEqual(0, m_write_file.call_count)
+
+    @mock.patch('cloudinit.config.cc_apt_pipelining.util.write_file')
+    def test_false_disables_pipelining(self, m_write_file):
+        """ensure that pipelining can be disabled with correct config"""
+        cc_apt_pipelining.handle(
+            'foo', {'apt_pipelining': 'false'}, None, mock.MagicMock(), None)
+        self.assertEqual(1, m_write_file.call_count)
+        args, _ = m_write_file.call_args
+        self.assertEqual(cc_apt_pipelining.DEFAULT_FILE, args[0])
+        self.assertIn('Pipeline-Depth "0"', args[1])
+
+# vi: ts=4 expandtab