"""Ganeti module."""
import logging
from typing import Dict, Optional
import requests
from requests.auth import HTTPBasicAuth
from requests.exceptions import Timeout
from spicerack.constants import PUPPET_CA_PATH
from spicerack.exceptions import SpicerackError
logger = logging.getLogger(__name__) # pylint: disable=invalid-name
# This is the template for the SVC URL for the RAPI end point
CLUSTER_SVC_URL = 'https://ganeti01.svc.{dc}.wmnet:5080'
# These are the configured available set of rows by Ganeti cluster DC
CLUSTERS_AND_ROWS = {'eqiad': ('A', 'C'), 'codfw': ('A', 'B'), 'esams': ('OE'),
'ulsfo': ('1'), 'eqsin': ('1')}
[docs]class GanetiError(SpicerackError):
"""Raised on errors from Ganeti operations."""
[docs]class GanetiRAPI:
"""Class which wraps the read-only Ganeti RAPI."""
def __init__(self, cluster_url: str, username: str, password: str, timeout: int, ca_path: str):
"""Initialize the instance.
Arguments:
cluster_url (str): the short name of the cluster to access.
username (str): the RAPI user name
password (str): the RAPI user's password
timeout (int): the timeout in seconds for each request
ca_path (str): the path to the signing certificate authority
"""
self._auth = HTTPBasicAuth(username, password)
self._ca_path = ca_path
self._url = cluster_url
self._timeout = timeout
def _api_get_request(self, *targets: str) -> Dict:
"""Perform a RAPI request.
Arguments:
*targets: The path components of the request (minus the /2/ part of the path)
Returns:
dict: The decoded JSON response
Raises:
spicerack.ganeti.GanetiError: on non-200 responses
"""
full_url = '/'.join([self._url, '2'] + list(targets))
try:
result = requests.get(full_url, auth=self._auth, verify=self._ca_path, timeout=self._timeout)
except Timeout as ex:
raise GanetiError('Timeout performing request to RAPI') from ex
if result.status_code != 200:
raise GanetiError('Non-200 from API: {}: {}'.format(result.status_code, result.text))
return result.json()
@property
def info(self) -> Dict:
"""Return complete cluster information.
Returns:
dict: Cluster information dictionary
Raises:
spicerack.ganeti.GanetiError: API errors
"""
return self._api_get_request('info')
@property
def master(self) -> Optional[str]:
"""Return the internal name for the current ganeti master node.
Returns:
str: The hostname of the master node (or None if the data is missing).
Raises:
spicerack.ganeti.GanetiError: API errors
"""
return self.info.get('master')
[docs] def fetch_instance(self, fqdn: str) -> Dict:
"""Return full information about an instance.
Arguments:
fqdn: the FQDN of the instance in question
Returns:
dict: host information
Raises:
spicerack.ganeti.GanetiError: API errors
"""
return self._api_get_request('instances', fqdn)
[docs] def fetch_instance_mac(self, fqdn: str) -> str:
"""Convenience method to return the 0th adapter's MAC address for an instance.
Note that we don't allow the creation of instances with more than one MAC address at this time.
Arguments:
fqdn: the FQDN of the instance in question
Returns:
str: MAC address
Raises:
GanetiError: API errors
"""
instance_info = self.fetch_instance(fqdn)
if 'nic.macs' not in instance_info or not instance_info['nic.macs']:
raise GanetiError("Can't find any MACs for instance")
return instance_info['nic.macs'][0]
[docs]class Ganeti:
"""Class which wraps all Ganeti clusters."""
def __init__(self, username: str, password: str, timeout: int):
"""Initialize the instance.
Arguments:
username (str): The RAPI username to use.
password (str): The RAPI password to use.
timeout (int): The timeout in seconds for each request to the API.
"""
self._username = username
self._password = password
self._timeout = timeout
[docs] def rapi(self, cluster: str) -> GanetiRAPI:
"""Return a RAPI object for a particular cluster.
Arguments:
cluster (str): the name of the cluster to get a RAPI for.
Returns:
spicerack.ganeti.GanetiRAPI: the RAPI interface object
Raises:
spicerack.ganeti.GanetiError: on an invalid cluster name
"""
if cluster not in CLUSTERS_AND_ROWS:
raise GanetiError('Cannot find cluster {} (expected {}).'.format(cluster, tuple(CLUSTERS_AND_ROWS.keys())))
cluster_url = CLUSTER_SVC_URL.format(dc=cluster)
return GanetiRAPI(cluster_url, self._username, self._password, self._timeout, PUPPET_CA_PATH)
[docs] def fetch_cluster_for_instance(self, fqdn: str) -> str:
"""Return the cluster name for a given FQDN if possible.
Arguments:
fqdn (str): The FQDN for the host to locate.
Returns:
str: The cluster name if found.
Raises:
spicerack.ganeti.GanetiError: if the host was not found in any configured cluster.
"""
for cluster in CLUSTERS_AND_ROWS:
cluster_rapi = self.rapi(cluster)
try:
cluster_rapi.fetch_instance(fqdn)
return cluster
except GanetiError:
continue
raise GanetiError("Cannot find {} in any configured cluster.".format(fqdn))