def test_workflow_host_select_condemned(mock_glbl_cfg):
"""Ensure condemned hosts are filtered out."""
mock_glbl_cfg(
'cylc.flow.host_select.glbl_cfg', f'''
[scheduler]
[[run hosts]]
available = {localhost}
condemned = {localhost_fqdn}
''')
with pytest.raises(HostSelectException) as excinfo:
select_workflow_host()
assert 'blacklisted' in str(excinfo.value)
assert 'condemned host' in str(excinfo.value)
def _can_auto_restart():
"""Determine whether this workflow can safely auto stop-restart."""
# Check whether there is currently an available host to restart on.
try:
select_workflow_host(cached=False)
except HostSelectException:
LOG.critical('Workflow cannot automatically restart because:\n' +
'No alternative host to restart workflow on.')
return False
except Exception:
# Any unexpected error in host selection shouldn't be able to take
# down the workflow.
LOG.critical('Workflow cannot automatically restart because:\n' +
'Error in host selection:\n' + traceback.format_exc())
return False
else:
return True
def test_workflow_host_select(mock_glbl_cfg):
"""Run the workflow_host_select mechanism."""
mock_glbl_cfg(
'cylc.flow.host_select.glbl_cfg', f'''
[scheduler]
[[run hosts]]
available= {localhost}
''')
assert select_workflow_host() == (localhost, localhost_fqdn)
def test_remote_workflow_host_select(mock_glbl_cfg):
"""test [scheduler][run hosts]available"""
mock_glbl_cfg(
'cylc.flow.host_select.glbl_cfg', f'''
[scheduler]
[[run hosts]]
available = {remote_platform}
''')
assert select_workflow_host() == (remote_platform, remote_platform_fqdn)
def _distribute(host):
"""Re-invoke this command on a different host if requested."""
# Check whether a run host is explicitly specified, else select one.
if not host:
host = select_workflow_host()[0]
if is_remote_host(host):
# Prevent recursive host selection
cmd = sys.argv[1:]
cmd.append("--host=localhost")
_remote_cylc_cmd(cmd, host=host)
sys.exit(0)
def test_workflow_host_select_default(mock_glbl_cfg):
"""Ensure "localhost" is provided as a default host."""
mock_glbl_cfg(
'cylc.flow.host_select.glbl_cfg', '''
[scheduler]
[[run hosts]]
available =
''')
hostname, host_fqdn = select_workflow_host()
assert hostname in localhost_aliases + [localhost]
assert host_fqdn == localhost_fqdn
def test_remote_workflow_host_condemned(mock_glbl_cfg):
"""test [scheduler][run hosts]condemned hosts"""
mock_glbl_cfg(
'cylc.flow.host_select.glbl_cfg', f'''
[scheduler]
[[run hosts]]
available = {remote_platform}, {local_host}
condemned = {remote_platform}
''')
for _ in range(10):
assert select_workflow_host() == (local_host, local_host_fqdn)
def test_remote_workflow_host_rankings(mock_glbl_cfg):
"""test [scheduler][run hosts]rankings"""
mock_glbl_cfg(
'cylc.flow.host_select.glbl_cfg', f'''
[scheduler]
[[run hosts]]
available = {remote_platform}
ranking = """
# if this test fails due to race conditions
# then you are very lucky
virtual_memory().available > 123456789123456789
cpu_count() > 512
disk_usage('/').free > 123456789123456789
"""
''')
with pytest.raises(HostSelectException) as excinfo:
select_workflow_host()
# ensure that host selection actually evaluated rankings
assert set(excinfo.value.data[remote_platform_fqdn]) == {
'virtual_memory().available > 123456789123456789', 'cpu_count() > 512',
"disk_usage('/').free > 123456789123456789"
}
# ensure that none of the rankings passed
assert not any(excinfo.value.data[remote_platform_fqdn].values())