def test_write_config_to_dest(self):
"""
This function checks 3 different cases for function 'write_config_to_dest'
1: checks when exports/config.json exist, the files are copied correctly
2: checks exports/config.json.template exist, the template is copied, and values inside the template are swapped by values
3: checks the configuration was correct when the above 2 cases do not apply
"""
def check_attr_in_json_file(json_file,
attr_name,
value,
second_attr=None):
# We don't check existance here, because in this context, files do exist
with open(json_file, "r") as f:
json_val = json.loads(f.read())
actual_val = json_val[attr_name][
second_attr] if second_attr else json_val[attr_name]
self.assertEqual(actual_val, value)
try:
# Prepare the temp directory for verification
tmpdir = tempfile.mkdtemp()
dest_location = os.path.sep.join([tmpdir, "dest"])
dest_location_config = os.path.join(dest_location, "config.json")
# Note: in this context, the location of exports should not matter, as we are only copying files from exports
# in this function
exports_location = os.path.join(tmpdir, "rootfs/exports")
exports_json = os.path.join(exports_location, "config.json")
os.makedirs(exports_location)
os.mkdir(dest_location)
values = {"test_one": "$hello_test"}
with open(exports_json, 'w') as json_file:
json_file.write(json.dumps(values, indent=4))
json_file.write("\n")
new_values = {"hello_test": "new_val"}
sc = SystemContainers()
sc._write_config_to_dest(dest_location, exports_location)
self.assertTrue(os.path.exists(dest_location_config), True)
check_attr_in_json_file(dest_location_config, "test_one",
"$hello_test")
# We remove the file to keep the destination clean for next operation
os.remove(dest_location_config)
# Rename exports/config.json to exports/config.json.template
os.rename(exports_json, exports_json + ".template")
sc._write_config_to_dest(dest_location, exports_location,
new_values)
self.assertTrue(os.path.exists(dest_location_config), True)
check_attr_in_json_file(dest_location_config, "test_one",
"new_val")
os.remove(dest_location_config)
# Note: in this case, the configuration is generated and changed via 'generate_default_oci_configuration' which uses runc.
# Thus, we assume when user tries to run the unit test with this function, he will have runc installed
sc._write_config_to_dest(dest_location,
os.path.join(tmpdir, "not_exist"))
self.assertTrue(os.path.exists(dest_location_config), True)
check_attr_in_json_file(dest_location_config,
"root",
"rootfs",
second_attr="path")
finally:
shutil.rmtree(tmpdir)
