Add unit test for cache-url

A sanity check that cache-url does the right thing when presented
with the appropriate curl return codes.  This change brings in the
test code for scripts from tripleo-image-elements, which needs to
be factored out into a place both projects can use it.

I'm stubbing out curl so we don't have a dep on curl in our unit
tests, and because I've seen some strange behavior out of curl in
the gate that caused random failures in this test.

Change-Id: I31e6b06b45415feec7285511d07e65eb78d0d045

.testr.conf

@@ -1,5 +1,10 @@
 [DEFAULT]
-test_command=python -m subunit.run discover . $LISTOPT $IDOPTION
+test_command=OS_STDOUT_CAPTURE=${OS_STDOUT_CAPTURE:-1} \
+             OS_STDERR_CAPTURE=${OS_STDERR_CAPTURE:-1} \
+             OS_LOG_CAPTURE=${OS_LOG_CAPTURE:-1} \
+             OS_TEST_TIMEOUT=${OS_TEST_TIMEOUT:-60} \
+             OS_DEBUG=${OS_DEBUG:-0} \
+             python -m subunit.run discover . $LISTOPT $IDOPTION
 test_id_option=--load-list $IDFILE
 test_list_option=--list
 

diskimage_builder/tests/base.py

@@ -0,0 +1,58 @@
+# Copyright 2014 Red Hat, Inc.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+# TODO(bnemec): This whole file is a copy-paste of the one in
+# tripleo-image-elements.  That duplication needs to be eliminated.
+
+import os
+import subprocess
+import sys
+import tempfile
+
+from oslotest import base
+
+
+class ScriptTestBase(base.BaseTestCase):
+    def setUp(self):
+        super(ScriptTestBase, self).setUp()
+        self.tmpdir = tempfile.mkdtemp()
+        self.env = os.environ.copy()
+        self.env['PATH'] = self.tmpdir + ':' + self.env['PATH']
+
+    def _stub_script(self, name, contents):
+        filename = os.path.join(self.tmpdir, name)
+        with open(filename, 'w') as f:
+            f.write('#!/bin/bash\n')
+            f.write(contents)
+            f.write('\n')
+        os.chmod(filename, 0o700)
+
+    def _run_command(self, cmd):
+        try:
+            # check_output doesn't exist in Python < 2.7
+            if sys.hexversion < 0x02070000:
+                runner = subprocess.check_call
+            else:
+                runner = subprocess.check_output
+            return runner(cmd,
+                          stderr=subprocess.STDOUT,
+                          env=self.env)
+        # NOTE(bnemec): Handle the exception so we can extract as much
+        # information as possible.
+        except subprocess.CalledProcessError as e:
+            # The check_call exception won't have any data in e.output
+            if sys.hexversion < 0x02070000:
+                self.fail(e)
+            else:
+                self.fail(e.output)

elements/cache-url/tests/test_cache_url.py

@@ -0,0 +1,41 @@
+# Copyright 2014 Red Hat, Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+# implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import os
+import tempfile
+import time
+
+from diskimage_builder.tests import base
+
+
+class TestCacheUrl(base.ScriptTestBase):
+    def test_cache_url_caches(self):
+        tempdir = tempfile.mkdtemp()
+        target = os.path.join(tempdir, 'target')
+        source = 'http://fake/url'
+        # Write fake data to the target file and return success
+        self._stub_script('curl', 'echo "test" > ${3:7:100}\necho 200')
+        self._run_command(['elements/cache-url/bin/cache-url',
+                           source,
+                           target])
+        self.assertTrue(os.path.exists(target))
+        modification_time = os.path.getmtime(target)
+        # Make sure that the timestamp would change if the file does
+        time.sleep(1)
+        self._stub_script('curl', 'echo "304"')
+        self._run_command(['elements/cache-url/bin/cache-url',
+                           source,
+                           target])
+        self.assertEqual(modification_time, os.path.getmtime(target))

test-requirements.txt

@@ -3,8 +3,6 @@
 # process, which may cause wedges in the gate later.
 hacking>=0.9.2,<0.10
 
-coverage>=3.6
 discover
 oslotest>=1.1.0  # Apache-2.0
 testrepository>=0.0.18
-testtools>=0.9.34