class CassandraNode:
"""
Class that represents a node in a cassandra cluster. Can be of type 'SEED' or 'REGULAR' (default)
"""
#static vars
image = env_vars["cassandra_base_image"]
def __init__(self, name=None, node_type="REGULAR", create=False, vm=None):
"""
Creates a CassandraNode object.
:param name:
:param node_type: if "SEED" then will be treated as seednode
:param create: if True then the actual VM will be created
:param vm: if not None then this CassandraNode will be created from an existing vm
"""
self.bootstraped = False
self.name = name
self.type = node_type
self.vm = None
if not vm is None:
# init a node from a VM
self.from_vm(vm)
if create:
self.create()
def __str__(self):
rv = "Cassandra Node || name: %s, type: %s" % (self.name, self.type)
return rv
def create(self):
"""
creates the VM that this Cassandra Node will run on
:return:
"""
flavor = env_vars["cassandra_%s_flavor" % self.type]
#create the VM
self.vm = VM(self.name, flavor, self.image, create=True)
def from_vm(self, vm):
"""
Creates a CassandraNode from an existing VM
:param vm:
:return:
"""
if not vm.created:
print "this VM is not created, so you cann't create a node from it"
self.name = vm.name
self.vm = vm
if "seed" in vm.name:
self.type = "SEED"
elif "client" in vm.name:
self.type = "CLIENT"
else:
self.type = "REGULAR"
def bootstrap(self, params = None):
"""
Bootstraps a node with the rest of the Casandra cluster
"""
command = ""
print "NODE: [%s] running bootstrap scripts" % self.name
if self.type == "SEED":
command += get_script_text("cassandra_seednode_bootstrap")
elif self.type == "CLIENT":
if self.name.endswith('1'):
command += get_script_text("ganglia_endpoint")
command += get_script_text("cassandra_client_bootstrap")
else:
command = get_script_text("cassandra_node_bootstrap")
timer = Timer.get_timer()
self.vm.run_command(command, silent=True)
print "NODE: %s is now bootstrapped (took %d sec)" % (self.name, timer.stop())
self.bootstraped = True
def decommission(self):
"""
Cecommissions a node from the Cassandra Cluster
:return:
"""
print "NODE: Decommissioning node: " + self.name
keyspace = env_vars['keyspace']
timer = Timer.get_timer()
self.vm.run_command("nodetool repair -h %s %s" % (self.name, keyspace))
self.vm.run_command("nodetool decommission")
print "NODE: %s is decommissioned (took %d secs)" % (self.name, timer.stop())
#self.vm.shutdown()
def kill(self):
command = get_script_text("cassandra_kill")
self.vm.run_command(command, silent=True)
def get_status(self):
"""
Gets the status of the node as far as Cassandra is concerned (uses hooks inside of VM)
:return:
"""
if self.vm.get_cloud_status() != "ACTIVE":
return "stopped"
#wait for the vm to be ready and SSH-able
self.vm.wait_ready()
status = self.vm.run_command("ctool status", indent=0, prefix='')
return status.strip()
def inject_server_hosts(self, hosts):
text = ""
for h in hosts:
text += h + "\n"
print "injecting: \n"+text
self.vm.run_command("echo '%s' > /opt/hosts")
def __str__(self):
str = "Node %s" % self.name
return str
