ansible-galaxy - fix collection installation with trailing slashes (#70016)

If we fail to find a member when extracting a directory, try adding a trailing
slash to the member name. In certain cases, the member in the tarfile will
contain a trailing slash but the file name in FILES.json will never contain
the trailing slash.

If unable to find the member, handle the KeyError and print a nicer error.

Also check if a directory exists before creating it since it may have been
extracted from the archive.

Fixes #70009

* Add unit tests
* Use loop for trying to get members

lib/ansible/galaxy/collection.py

@@ -1384,7 +1384,23 @@ def _download_file(url, b_path, expected_hash, validate_certs, headers=None):
 
 def _extract_tar_dir(tar, dirname, b_dest):
     """ Extracts a directory from a collection tar. """
-    tar_member = tar.getmember(to_native(dirname, errors='surrogate_or_strict'))
+    member_names = [to_native(dirname, errors='surrogate_or_strict')]
+
+    # Create list of members with and without trailing separator
+    if not member_names[-1].endswith(os.path.sep):
+        member_names.append(member_names[-1] + os.path.sep)
+
+    # Try all of the member names and stop on the first one that are able to successfully get
+    for member in member_names:
+        try:
+            tar_member = tar.getmember(member)
+        except KeyError:
+            continue
+        break
+    else:
+        # If we still can't find the member, raise a nice error.
+        raise AnsibleError("Unable to extract '%s' from collection" % to_native(member, errors='surrogate_or_strict'))
+
     b_dir_path = os.path.join(b_dest, to_bytes(dirname, errors='surrogate_or_strict'))
 
     b_parent_path = os.path.dirname(b_dir_path)
@@ -1403,7 +1419,8 @@ def _extract_tar_dir(tar, dirname, b_dest):
         os.symlink(b_link_path, b_dir_path)
 
     else:
-        os.mkdir(b_dir_path, 0o0755)
+        if not os.path.isdir(b_dir_path):
+            os.mkdir(b_dir_path, 0o0755)
 
 
 def _extract_tar_file(tar, filename, b_dest, b_temp_path, expected_hash=None):

test/units/cli/galaxy/test_collection_extract_tar.py

@@ -0,0 +1,61 @@
+# -*- coding: utf-8 -*-
+# Copyright (c) 2020 Ansible Project
+# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
+
+from __future__ import absolute_import, division, print_function
+__metaclass__ = type
+
+import pytest
+
+from ansible.errors import AnsibleError
+from ansible.galaxy.collection import _extract_tar_dir
+
+
+@pytest.fixture
+def fake_tar_obj(mocker):
+    m_tarfile = mocker.Mock()
+    m_tarfile.type = mocker.Mock(return_value=b'99')
+    m_tarfile.SYMTYPE = mocker.Mock(return_value=b'22')
+
+    return m_tarfile
+
+
+def test_extract_tar_member_trailing_sep(mocker):
+    m_tarfile = mocker.Mock()
+    m_tarfile.getmember = mocker.Mock(side_effect=KeyError)
+
+    with pytest.raises(AnsibleError, match='Unable to extract'):
+        _extract_tar_dir(m_tarfile, '/some/dir/', b'/some/dest')
+
+    assert m_tarfile.getmember.call_count == 1
+
+
+def test_extract_tar_member_no_trailing_sep(mocker):
+    m_tarfile = mocker.Mock()
+    m_tarfile.getmember = mocker.Mock(side_effect=KeyError)
+
+    with pytest.raises(AnsibleError, match='Unable to extract'):
+        _extract_tar_dir(m_tarfile, '/some/dir', b'/some/dest')
+
+    assert m_tarfile.getmember.call_count == 2
+
+
+def test_extract_tar_dir_exists(mocker, fake_tar_obj):
+    mocker.patch('os.makedirs', return_value=None)
+    m_makedir = mocker.patch('os.mkdir', return_value=None)
+    mocker.patch('os.path.isdir', return_value=True)
+
+    _extract_tar_dir(fake_tar_obj, '/some/dir', b'/some/dest')
+
+    assert not m_makedir.called
+
+
+def test_extract_tar_dir_does_not_exist(mocker, fake_tar_obj):
+    mocker.patch('os.makedirs', return_value=None)
+    m_makedir = mocker.patch('os.mkdir', return_value=None)
+    mocker.patch('os.path.isdir', return_value=False)
+
+    _extract_tar_dir(fake_tar_obj, '/some/dir', b'/some/dest')
+
+    assert m_makedir.called
+    assert m_makedir.call_args[0] == (b'/some/dir', 0o0755)