c7475b06be
We want to default to running all tox environments under python 3, so set the basepython value in each environment. We do not want to specify a minor version number, because we do not want to have to update the file every time we upgrade python. We do not want to set the override once in testenv, because that breaks the more specific versions used in default environments like py35 and py36. Change-Id: Id5511088f9b29a801156231f6b95d6add8b68cd5 Signed-off-by: Doug Hellmann <doug@doughellmann.com> |
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.gitignore | ||
.gitreview | ||
.zuul.yaml | ||
README.md | ||
common.py | ||
copyright | ||
interface.yaml | ||
requires.py | ||
test-requirements.txt | ||
tox.ini |
README.md
Overview
This interface handles the communication with the hacluster subordinate
charm using the ha
interface protocol.
Usage
Requires
The interface layer will set the following reactive states, as appropriate:
-
{relation_name}.connected
The relation is established and ready for the local charm to configure the hacluster subordinate charm. The configuration of the resources to manage for the hacluster charm can be managed via one of the following methods:manage_resources
methodbind_on
method
Configuration of the managed resources within the hacluster can be managed by passing
common.CRM
object definitions to themanage_resources
method. -
{relation_name}.available
The hacluster is up and ready.
For example:
from charms.reactive import when, when_not
from charms.reactive import set_state, remove_state
from relations.hacluster.common import CRM
@when('ha.connected')
def cluster_connected(hacluster):
resources = CRM()
resources.primitive('res_vip', 'ocf:IPAddr2',
params='ip=10.0.3.100 nic=eth0',
op='monitor interval="10s"')
resources.clone('cl_res_vip', 'res_vip')
hacluster.bind_on(iface='eth0', mcastport=4430)
hacluster.manage_resources(resources)
Additionally, for more code clarity a custom object implements the interface defined in common.ResourceDescriptor can be used to simplify the code for reuse.
For example:
import ipaddress
from relation.hacluster.common import CRM
from relation.hacluster.common import ResourceDescriptor
class VirtualIP(ResourceDescriptor):
def __init__(self, vip, nic='eth0'):
self.vip = vip
self.nic = 'eth0'
def configure_resource(self, crm):
ipaddr = ipaddress.ip_address(self.vip)
if isinstance(ipaddr, ipaddress.IPv4Address):
res_type = 'ocf:heartbeat:IPAddr2'
res_parms = 'ip={ip} nic={nic}'.format(ip=self.vip,
nic=self.nic)
else:
res_type = 'ocf:heartbeat:IPv6addr'
res_params = 'ipv6addr={ip} nic={nic}'.format(ip=self.vip,
nic=self.nic)
crm.primitive('res_vip', res_type, params=res_params,
op='monitor interval="10s"')
crm.clone('cl_res_vip', 'res_vip')
Once the VirtualIP class above has been defined in charm code, it can make the code a bit cleaner. The example above can thusly be written as:
@when('ha.connected')
def cluster_connected(hacluster):
resources = CRM()
resources.add(VirtualIP('10.0.3.100'))
hacluster.bind_on(iface='eth0', mcastport=4430)
hacluster.manage_resources(resources)