Permalink
345 lines (291 sloc) 12.5 KB
#!/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
# 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
try:
import configparser
except ImportError:
import ConfigParser as configparser
import os
import re
import sys
ROLES = ['all', 'kube-master', 'kube-node', 'etcd', 'k8s-cluster:children',
'calico-rr', 'vault']
PROTECTED_NAMES = ROLES
AVAILABLE_COMMANDS = ['help', 'print_cfg', 'print_ips', 'load']
_boolean_states = {'1': True, 'yes': True, 'true': True, 'on': True,
'0': False, 'no': False, 'false': False, 'off': False}
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.ini")
# Reconfigures cluster distribution at scale
SCALE_THRESHOLD = int(os.environ.get("SCALE_THRESHOLD", 50))
MASSIVE_SCALE_THRESHOLD = int(os.environ.get("SCALE_THRESHOLD", 200))
DEBUG = get_var_as_bool("DEBUG", True)
HOST_PREFIX = os.environ.get("HOST_PREFIX", "node")
# Configurable as shell vars end
class KubesprayInventory(object):
def __init__(self, changed_hosts=None, config_file=None):
self.config = configparser.ConfigParser(allow_no_value=True,
delimiters=('\t', ' '))
self.config_file = config_file
if self.config_file:
self.config.read(self.config_file)
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:
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()
self.set_etcd(list(self.hosts.keys())[:3])
if len(self.hosts) >= SCALE_THRESHOLD:
self.set_kube_master(list(self.hosts.keys())[3:5])
else:
self.set_kube_master(list(self.hosts.keys())[:2])
self.set_kube_node(self.hosts.keys())
if len(self.hosts) >= SCALE_THRESHOLD:
self.set_calico_rr(list(self.hosts.keys())[:3])
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(config_file, 'w') as f:
self.config.write(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):
opts = optstring.split(' ')
for opt in opts:
if '=' not in opt:
continue
k, v = opt.split('=')
if k == "ip":
return v
raise ValueError("IP parameter not found in options")
def ensure_required_groups(self, groups):
for group in groups:
try:
self.debug("Adding group {0}".format(group))
self.config.add_section(group)
except configparser.DuplicateSectionError:
pass
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, opts in self.config.items('all'):
existing_hosts[host] = opts
host_id = self.get_host_id(host)
if host_id > highest_host_id:
highest_host_id = host_id
except configparser.NoSectionError:
pass
# FIXME(mattymo): Fix condition where delete then add reuses highest id
next_host_id = highest_host_id + 1
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 self.exists_hostname(all_hosts, host):
self.debug("Skipping existing host {0}.".format(host))
continue
elif self.exists_ip(all_hosts, host):
self.debug("Skipping existing host {0}.".format(host))
continue
next_host = "{0}{1}".format(HOST_PREFIX, next_host_id)
next_host_id += 1
all_hosts[next_host] = "ansible_host={0} ip={1}".format(
host, host)
elif host[0].isalpha():
raise Exception("Adding hosts by hostname is not supported.")
return all_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.config.sections():
for host, _ in self.config.items(role):
if host not in hostnames and host not in protected_names:
self.debug("Host {0} removed from role {1}".format(host,
role))
self.config.remove_option(role, host)
def add_host_to_group(self, group, host, opts=""):
self.debug("adding host {0} to group {1}".format(host, group))
self.config.set(group, host, opts)
def set_kube_master(self, hosts):
for host in hosts:
self.add_host_to_group('kube-master', 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):
self.add_host_to_group('k8s-cluster:children', 'kube-node')
self.add_host_to_group('k8s-cluster:children', 'kube-master')
def set_calico_rr(self, hosts):
for host in hosts:
if host in self.config.items('kube-master'):
self.debug("Not adding {0} to calico-rr group because it "
"conflicts with kube-master group".format(host))
continue
if host in self.config.items('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.config['all']) >= SCALE_THRESHOLD:
if self.config.has_option('etcd', host):
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.config['all']) >= MASSIVE_SCALE_THRESHOLD:
if self.config.has_option('kube-master', host):
self.debug("Not adding {0} to kube-node group because of "
"scale deployment and host is in kube-master "
"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)
self.add_host_to_group('vault', host)
def load_file(self, files=None):
'''Directly loads JSON, or YAML file to inventory.'''
if not files:
raise Exception("No input file specified.")
import json
import yaml
for filename in list(files):
# Try JSON, then YAML
try:
with open(filename, 'r') as f:
data = json.load(f)
except ValueError:
try:
with open(filename, 'r') as f:
data = yaml.load(f)
print("yaml")
except ValueError:
raise Exception("Cannot read %s as JSON, YAML, 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={0} ip={0}".format(opts['ip'])
for key, val in opts.items():
if key == "ip":
continue
optstring += " {0}={1}".format(key, val)
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 == '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
Advanced usage:
Add another host after initial creation: inventory.py 10.10.1.5
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.ini
HOST_PREFIX Host prefix for generated hosts. Default: node
SCALE_THRESHOLD Separate ETCD role if # of nodes >= 50
MASSIVE_SCALE_THRESHOLD Separate K8s master and ETCD if # of nodes >= 200
'''
print(help_text)
def print_config(self):
self.config.write(sys.stdout)
def print_ips(self):
ips = []
for host, opts in self.config.items('all'):
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)
if __name__ == "__main__":
sys.exit(main())