Merge lp:~niedbalski/charm-helpers/sed-support into lp:charm-helpers

[Jorge Niedbalski]

Add a 'sed' function for search/replace patterns on files.

[Felipe Reyes (freyes)]

I had to apply this patch[0] to be able to run the unit tests, it seems to be a recent regression/change according to this[1] stackoverflow question found by @niedbalski.

[0]
=== modified file 'test_requirements.txt'
--- test_requirements.txt 2014-11-25 15:07:02 +0000
+++ test_requirements.txt 2015-07-15 16:57:37 +0000
@@ -3,7 +3,7 @@
 pip
 distribute
 coverage>=3.6
-mock>=1.0.1
+mock>=1.0.1,<1.1.0
 nose>=1.3.1
 flake8
 testtools==0.9.14 # Before dependent on modern 'six'

[1] http://stackoverflow.com/questions/31417964/importerror-cannot-import-name-wraps

[Felipe Reyes (freyes)]

> I had to apply this patch[0] to be able to run the unit tests, it seems to be
> a recent regression/change according to this[1] stackoverflow question found
> by @niedbalski.
sent MP https://code.launchpad.net/~freyes/charm-helpers/mock/+merge/264884 to fix it

[Felipe Reyes (freyes)]

@niedbalski, I found a few minor issues, besides those lgtm

review: Needs Fixing

[Felipe Reyes (freyes)]

thanks @niedbalski!, lgtm

review: Approve

=== added file 'charmhelpers/core/files.py'
--- charmhelpers/core/files.py	1970-01-01 00:00:00 +0000
+++ charmhelpers/core/files.py	2015-07-22 13:55:55 +0000
@@ -0,0 +1,45 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+# Copyright 2014-2015 Canonical Limited.
+#
+# This file is part of charm-helpers.
+#
+# charm-helpers is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License version 3 as
+# published by the Free Software Foundation.
+#
+# charm-helpers is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with charm-helpers.  If not, see <http://www.gnu.org/licenses/>.
+
+__author__ = 'Jorge Niedbalski <[e-mail]>'
+
+import os
+import subprocess
+
+
+def sed(filename, before, after, flags='g'):
+    """
+    Search and replaces the given pattern on filename.
+
+    :param filename: relative or absolute file path.
+    :param before: expression to be replaced (see 'man sed')
+    :param after: expression to replace with (see 'man sed')
+    :param flags: sed-compatible regex flags in example, to make
+    the  search and replace case insensitive, specify ``flags="i"``.
+    The ``g`` flag is always specified regardless, so you do not
+    need to remember to include it when overriding this parameter.
+    :returns: If the sed command exit code was zero then return,
+    otherwise raise CalledProcessError.
+    """
+    expression = r's/{0}/{1}/{2}'.format(before,
+                                         after, flags)
+
+    return subprocess.check_call(["sed", "-i", "-r", "-e",
+                                  expression,
+                                  os.path.expanduser(filename)])

=== added file 'tests/core/test_files.py'
--- tests/core/test_files.py	1970-01-01 00:00:00 +0000
+++ tests/core/test_files.py	2015-07-22 13:55:55 +0000
@@ -0,0 +1,32 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+from charmhelpers.core import files
+
+import mock
+import unittest
+import tempfile
+import os
+
+
+class FileTests(unittest.TestCase):
+
+    @mock.patch("subprocess.check_call")
+    def test_sed(self, check_call):
+        files.sed("/tmp/test-sed-file", "replace", "this")
+        check_call.assert_called_once_with(
+            ['sed', '-i', '-r', '-e', 's/replace/this/g',
+             '/tmp/test-sed-file']
+        )
+
+    def test_sed_file(self):
+        tmp = tempfile.NamedTemporaryFile(delete=False)
+        tmp.write("IPV6=yes")
+        tmp.close()
+
+        files.sed(tmp.name, "IPV6=.*", "IPV6=no")
+
+        with open(tmp.name) as tmp:
+            self.assertEquals(tmp.read(), "IPV6=no")
+
+        os.unlink(tmp.name)