#!/usr/bin/env python3
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
# implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
# Usage: inventory.py ip1 [ip2 ...]
# Examples: inventory.py 10.10.1.3 10.10.1.4 10.10.1.5
#
# Advanced usage:
# Add another host after initial creation: inventory.py 10.10.1.5
# Add range of hosts: inventory.py 10.10.1.3-10.10.1.5
# Add hosts with different ip and access ip:
# inventory.py 10.0.0.1,192.168.10.1 10.0.0.2,192.168.10.2 10.0.0.3,192.168.1.3
# Add hosts with a specific hostname, ip, and optional access ip:
# inventory.py first,10.0.0.1,192.168.10.1 second,10.0.0.2 last,10.0.0.3
# Delete a host: inventory.py -10.10.1.3
# Delete a host by id: inventory.py -node1
#
# Load a YAML or JSON file with inventory data: inventory.py load hosts.yaml
# YAML file should be in the following format:
# group1:
# host1:
# ip: X.X.X.X
# var: val
# group2:
# host2:
# ip: X.X.X.X
from collections import OrderedDict
from ipaddress import ip_address
from ruamel.yaml import YAML
import os
import re
import subprocess
import sys
ROLES = ['all', 'kube_control_plane', 'kube_node', 'etcd', 'k8s_cluster',
'calico_rr']
PROTECTED_NAMES = ROLES
AVAILABLE_COMMANDS = ['help', 'print_cfg', 'print_ips', 'print_hostnames',
'load']
_boolean_states = {'1': True, 'yes': True, 'true': True, 'on': True,
'0': False, 'no': False, 'false': False, 'off': False}
yaml = YAML()
yaml.Representer.add_representer(OrderedDict, yaml.Representer.represent_dict)
def get_var_as_bool(name, default):
value = os.environ.get(name, '')
return _boolean_states.get(value.lower(), default)
# Configurable as shell vars start
CONFIG_FILE = os.environ.get("CONFIG_FILE", "./inventory/sample/hosts.yaml")
# Remove the reference of KUBE_MASTERS after some deprecation cycles.
KUBE_CONTROL_HOSTS = int(os.environ.get("KUBE_CONTROL_HOSTS",
os.environ.get("KUBE_MASTERS", 2)))
# Reconfigures cluster distribution at scale
SCALE_THRESHOLD = int(os.environ.get("SCALE_THRESHOLD", 50))
MASSIVE_SCALE_THRESHOLD = int(os.environ.get("MASSIVE_SCALE_THRESHOLD", 200))
DEBUG = get_var_as_bool("DEBUG", True)
HOST_PREFIX = os.environ.get("HOST_PREFIX", "node")
USE_REAL_HOSTNAME = get_var_as_bool("USE_REAL_HOSTNAME", False)
# Configurable as shell vars end
class KubesprayInventory(object):
def __init__(self, changed_hosts=None, config_file=None):
self.config_file = config_file
self.yaml_config = {}
if self.config_file:
try:
self.hosts_file = open(config_file, 'r')
self.yaml_config = yaml.load_all(self.hosts_file)
except OSError:
pass
if changed_hosts and changed_hosts[0] in AVAILABLE_COMMANDS:
self.parse_command(changed_hosts[0], changed_hosts[1:])
sys.exit(0)
self.ensure_required_groups(ROLES)
if changed_hosts:
changed_hosts = self.range2ips(changed_hosts)
self.hosts = self.build_hostnames(changed_hosts)
self.purge_invalid_hosts(self.hosts.keys(), PROTECTED_NAMES)
self.set_all(self.hosts)
self.set_k8s_cluster()
etcd_hosts_count = 3 if len(self.hosts.keys()) >= 3 else 1
self.set_etcd(list(self.hosts.keys())[:etcd_hosts_count])
if len(self.hosts) >= SCALE_THRESHOLD:
self.set_kube_control_plane(list(self.hosts.keys())[
etcd_hosts_count:(etcd_hosts_count + KUBE_CONTROL_HOSTS)])
else:
self.set_kube_control_plane(
list(self.hosts.keys())[:KUBE_CONTROL_HOSTS])
self.set_kube_node(self.hosts.keys())
if len(self.hosts) >= SCALE_THRESHOLD:
self.set_calico_rr(list(self.hosts.keys())[:etcd_hosts_count])
else: # Show help if no options
self.show_help()
sys.exit(0)
self.write_config(self.config_file)
def write_config(self, config_file):
if config_file:
with open(self.config_file, 'w') as f:
yaml.dump(self.yaml_config, f)
else:
print("WARNING: Unable to save config. Make sure you set "
"CONFIG_FILE env var.")
def debug(self, msg):
if DEBUG:
print("DEBUG: {0}".format(msg))
def get_ip_from_opts(self, optstring):
if 'ip' in optstring:
return optstring['ip']
else:
raise ValueError("IP parameter not found in options")
def ensure_required_groups(self, groups):
for group in groups:
if group == 'all':
self.debug("Adding group {0}".format(group))
if group not in self.yaml_config:
all_dict = OrderedDict([('hosts', OrderedDict({})),
('children', OrderedDict({}))])
self.yaml_config = {'all': all_dict}
else:
self.debug("Adding group {0}".format(group))
if group not in self.yaml_config['all']['children']:
self.yaml_config['all']['children'][group] = {'hosts': {}}
def get_host_id(self, host):
'''Returns integer host ID (without padding) from a given hostname.'''
try:
short_hostname = host.split('.')[0]
return int(re.findall("\\d+$", short_hostname)[-1])
except IndexError:
raise ValueError("Host name must end in an integer")
def build_hostnames(self, changed_hosts):
existing_hosts = OrderedDict()
highest_host_id = 0
try:
for host in self.yaml_config['all']['hosts']:
existing_hosts[host] = self.yaml_config['all']['hosts'][host]
host_id = self.get_host_id(host)
if host_id > highest_host_id:
highest_host_id = host_id
except Exception:
pass
# FIXME(mattymo): Fix condition where delete then add reuses highest id
next_host_id = highest_host_id + 1
next_host = ""
all_hosts = existing_hosts.copy()
for host in changed_hosts:
if host[0] == "-":
realhost = host[1:]
if self.exists_hostname(all_hosts, realhost):
self.debug("Marked {0} for deletion.".format(realhost))
all_hosts.pop(realhost)
elif self.exists_ip(all_hosts, realhost):
self.debug("Marked {0} for deletion.".format(realhost))
self.delete_host_by_ip(all_hosts, realhost)
elif host[0].isdigit():
if ',' in host:
ip, access_ip = host.split(',')
else:
ip = host
access_ip = host
if self.exists_hostname(all_hosts, host):
self.debug("Skipping existing host {0}.".format(host))
continue
elif self.exists_ip(all_hosts, ip):
self.debug("Skipping existing host {0}.".format(ip))
continue
if USE_REAL_HOSTNAME:
cmd = ("ssh -oStrictHostKeyChecking=no "
+ access_ip + " 'hostname -s'")
next_host = subprocess.check_output(cmd, shell=True)
next_host = next_host.strip().decode('ascii')
else:
next_host = "{0}{1}".format(HOST_PREFIX, next_host_id)
next_host_id += 1
all_hosts[next_host] = {'ansible_host': access_ip,
'ip': ip,
'access_ip': access_ip}
elif host[0].isalpha():
if ',' in host:
try:
hostname, ip, access_ip = host.split(',')
except Exception:
hostname, ip = host.split(',')
access_ip = ip
if self.exists_hostname(all_hosts, host):
self.debug("Skipping existing host {0}.".format(host))
continue
elif self.exists_ip(all_hosts, ip):
self.debug("Skipping existing host {0}.".format(ip))
continue
all_hosts[hostname] = {'ansible_host': access_ip,
'ip': ip,
'access_ip': access_ip}
return all_hosts
def range2ips(self, hosts):
reworked_hosts = []
def ips(start_address, end_address):
try:
# Python 3.x
start = int(ip_address(start_address))
end = int(ip_address(end_address))
except Exception:
# Python 2.7
start = int(ip_address(str(start_address)))
end = int(ip_address(str(end_address)))
return [ip_address(ip).exploded for ip in range(start, end + 1)]
for host in hosts:
if '-' in host and not (host.startswith('-') or host[0].isalpha()):
start, end = host.strip().split('-')
try:
reworked_hosts.extend(ips(start, end))
except ValueError:
raise Exception("Range of ip_addresses isn't valid")
else:
reworked_hosts.append(host)
return reworked_hosts
def exists_hostname(self, existing_hosts, hostname):
return hostname in existing_hosts.keys()
def exists_ip(self, existing_hosts, ip):
for host_opts in existing_hosts.values():
if ip == self.get_ip_from_opts(host_opts):
return True
return False
def delete_host_by_ip(self, existing_hosts, ip):
for hostname, host_opts in existing_hosts.items():
if ip == self.get_ip_from_opts(host_opts):
del existing_hosts[hostname]
return
raise ValueError("Unable to find host by IP: {0}".format(ip))
def purge_invalid_hosts(self, hostnames, protected_names=[]):
for role in self.yaml_config['all']['children']:
if role != 'k8s_cluster' and self.yaml_config['all']['children'][role]['hosts']: # noqa
all_hosts = self.yaml_config['all']['children'][role]['hosts'].copy() # noqa
for host in all_hosts.keys():
if host not in hostnames and host not in protected_names:
self.debug(
"Host {0} removed from role {1}".format(host, role)) # noqa
del self.yaml_config['all']['children'][role]['hosts'][host] # noqa
# purge from all
if self.yaml_config['all']['hosts']:
all_hosts = self.yaml_config['all']['hosts'].copy()
for host in all_hosts.keys():
if host not in hostnames and host not in protected_names:
self.debug("Host {0} removed from role all".format(host))
del self.yaml_config['all']['hosts'][host]
def add_host_to_group(self, group, host, opts=""):
self.debug("adding host {0} to group {1}".format(host, group))
if group == 'all':
if self.yaml_config['all']['hosts'] is None:
self.yaml_config['all']['hosts'] = {host: None}
self.yaml_config['all']['hosts'][host] = opts
elif group != 'k8s_cluster:children':
if self.yaml_config['all']['children'][group]['hosts'] is None:
self.yaml_config['all']['children'][group]['hosts'] = {
host: None}
else:
self.yaml_config['all']['children'][group]['hosts'][host] = None # noqa
def set_kube_control_plane(self, hosts):
for host in hosts:
self.add_host_to_group('kube_control_plane', host)
def set_all(self, hosts):
for host, opts in hosts.items():
self.add_host_to_group('all', host, opts)
def set_k8s_cluster(self):
k8s_cluster = {'children': {'kube_control_plane': None,
'kube_node': None}}
self.yaml_config['all']['children']['k8s_cluster'] = k8s_cluster
def set_calico_rr(self, hosts):
for host in hosts:
if host in self.yaml_config['all']['children']['kube_control_plane']: # noqa
self.debug("Not adding {0} to calico_rr group because it "
"conflicts with kube_control_plane "
"group".format(host))
continue
if host in self.yaml_config['all']['children']['kube_node']:
self.debug("Not adding {0} to calico_rr group because it "
"conflicts with kube_node group".format(host))
continue
self.add_host_to_group('calico_rr', host)
def set_kube_node(self, hosts):
for host in hosts:
if len(self.yaml_config['all']['hosts']) >= SCALE_THRESHOLD:
if host in self.yaml_config['all']['children']['etcd']['hosts']: # noqa
self.debug("Not adding {0} to kube_node group because of "
"scale deployment and host is in etcd "
"group.".format(host))
continue
if len(self.yaml_config['all']['hosts']) >= MASSIVE_SCALE_THRESHOLD: # noqa
if host in self.yaml_config['all']['children']['kube_control_plane']['hosts']: # noqa
self.debug("Not adding {0} to kube_node group because of "
"scale deployment and host is in "
"kube_control_plane group.".format(host))
continue
self.add_host_to_group('kube_node', host)
def set_etcd(self, hosts):
for host in hosts:
self.add_host_to_group('etcd', host)
def load_file(self, files=None):
'''Directly loads JSON to inventory.'''
if not files:
raise Exception("No input file specified.")
import json
for filename in list(files):
# Try JSON
try:
with open(filename, 'r') as f:
data = json.load(f)
except ValueError:
raise Exception("Cannot read %s as JSON, or CSV", filename)
self.ensure_required_groups(ROLES)
self.set_k8s_cluster()
for group, hosts in data.items():
self.ensure_required_groups([group])
for host, opts in hosts.items():
optstring = {'ansible_host': opts['ip'],
'ip': opts['ip'],
'access_ip': opts['ip']}
self.add_host_to_group('all', host, optstring)
self.add_host_to_group(group, host)
self.write_config(self.config_file)
def parse_command(self, command, args=None):
if command == 'help':
self.show_help()
elif command == 'print_cfg':
self.print_config()
elif command == 'print_ips':
self.print_ips()
elif command == 'print_hostnames':
self.print_hostnames()
elif command == 'load':
self.load_file(args)
else:
raise Exception("Invalid command specified.")
def show_help(self):
help_text = '''Usage: inventory.py ip1 [ip2 ...]
Examples: inventory.py 10.10.1.3 10.10.1.4 10.10.1.5
Available commands:
help - Display this message
print_cfg - Write inventory file to stdout
print_ips - Write a space-delimited list of IPs from "all" group
print_hostnames - Write a space-delimited list of Hostnames from "all" group
Advanced usage:
Add another host after initial creation: inventory.py 10.10.1.5
Add range of hosts: inventory.py 10.10.1.3-10.10.1.5
Add hosts with different ip and access ip: inventory.py 10.0.0.1,192.168.10.1 10.0.0.2,192.168.10.2 10.0.0.3,192.168.10.3
Add hosts with a specific hostname, ip, and optional access ip: first,10.0.0.1,192.168.10.1 second,10.0.0.2 last,10.0.0.3
Delete a host: inventory.py -10.10.1.3
Delete a host by id: inventory.py -node1
Configurable env vars:
DEBUG Enable debug printing. Default: True
CONFIG_FILE File to write config to Default: ./inventory/sample/hosts.yaml
HOST_PREFIX Host prefix for generated hosts. Default: node
KUBE_CONTROL_HOSTS Set the number of kube-control-planes. Default: 2
SCALE_THRESHOLD Separate ETCD role if # of nodes >= 50
MASSIVE_SCALE_THRESHOLD Separate K8s control-plane and ETCD if # of nodes >= 200
''' # noqa
print(help_text)
def print_config(self):
yaml.dump(self.yaml_config, sys.stdout)
def print_hostnames(self):
print(' '.join(self.yaml_config['all']['hosts'].keys()))
def print_ips(self):
ips = []
for host, opts in self.yaml_config['all']['hosts'].items():
ips.append(self.get_ip_from_opts(opts))
print(' '.join(ips))
def main(argv=None):
if not argv:
argv = sys.argv[1:]
KubesprayInventory(argv, CONFIG_FILE)
return 0
if __name__ == "__main__":
sys.exit(main())