'kube-network' option

bin/kargo

@@ -16,7 +16,7 @@
 #    You should have received a copy of the GNU General Public License
 #    along with Foobar.  If not, see <http://www.gnu.org/licenses/>.
 
-__version__ = '0.2.3'
+__version__ = '0.2.4'
 
 import os
 import argparse
@@ -69,17 +69,18 @@ if __name__ == '__main__':
     )
     subparsers = parser.add_subparsers(help='commands')
 
+    parser.add_argument(
+        '-v', '--version', action='version',
+        version='%(prog)s'+' %s' %  __version__
+    )
+
     # Options shared by all subparsers
     parent_parser = argparse.ArgumentParser(add_help=False)
     parent_parser.add_argument(
         '-p', '--path', dest='kargo_path',
         help='Where the Ansible playbooks are installed'
     )
     parent_parser.add_argument('--config', dest='configfile', help="Config file")
-    parser.add_argument(
-        '--version', action='version',
-        version='%(prog)s'+' %s' %  __version__
-    )
     parent_parser.add_argument(
         '-y', '--assumeyes', default=False, dest='assume_yes', action='store_true',
         help='When a yes/no prompt would be presented, assume that the user entered "yes"'
@@ -177,12 +178,19 @@ if __name__ == '__main__':
         help='Create GCE machines and generate inventory'
     )
     deploy_parser.add_argument(
-        '-k', '--sshkey', dest='ssh_key', help='ssh key for authentication on remote servers'
+        '-k', '--sshkey', dest='ssh_key',
+        help='ssh key for authentication on remote servers'
     )
     deploy_parser.add_argument(
         '-u', '--user', dest='ansible_user', default=getpass.getuser(),
         help='Ansible SSH user (remote user)'
     )
+    deploy_parser.add_argument(
+        '-N', '--kube-network', dest='kube_network', default='10.233.0.0/16',
+        help="""Network to be used inside the cluster (/16),
+             (must not overlap with any of your infrastructure networks).
+             default: 10.233.0.0/16"""
+    )
     deploy_parser.add_argument(
         '-n', '--network-plugin', default='flannel',
         choices=['flannel', 'weave', 'calico']

setup.py

@@ -19,7 +19,7 @@
 
 setup(
     name='kargo',
-    version='0.2.3',
+    version='0.2.4',
     description="Kargo kubernetes cluster deployment",
     author="Smaine Kahlouch",
     author_email='smainklh@gmail.com',

src/kargo/__init__.py

@@ -1,3 +1,3 @@
 # (c) 2016, Smaine Kahlouch <smainklh@gmail.com>
 __author__ = 'smana'
-__version__ = '0.2.3'
+__version__ = '0.2.4'

src/kargo/cloud.py

@@ -25,6 +25,8 @@
 
 import sys
 import os
+import requests
+import random
 import yaml
 import json
 from kargo.inventory import CfgInventory
@@ -130,6 +132,16 @@ def create_instances(self):
             self.logger.critical('Cannot create instances: %s' % emsg)
             sys.exit(1)
 
+    def get_cluster_name(self):
+        try:
+            word_site = "http://svnweb.freebsd.org/csrg/share/dict/words?view=co&content-type=text/plain"
+            response = requests.get(word_site)
+            words = response.content.splitlines()
+            cluster_name = random.choice(words).decode("utf-8")
+        except:
+            cluster_name = id_generator()
+        return(cluster_name)
+
 
 class AWS(Cloud):
 
@@ -193,6 +205,7 @@ def gen_gce_playbook(self):
         ]
         # Define instance names
         gce_instance_names = list()
+        cluster_name = self.get_cluster_name()
         for x in range(self.options['count']):
             if self.options['add_node']:
                 current_inventory = self.Cfg.read_inventory()
@@ -202,10 +215,14 @@ def gen_gce_playbook(self):
                 gce_instance_names.append(
                     cluster_name + '-%s' % id_generator()
                 )
-            else:
+            elif 'cluster_name' in self.options.keys():
                 gce_instance_names.append(
                     self.options['cluster_name'] + '-%s' % id_generator()
                 )
+            else:
+                gce_instance_names.append(
+                    'k8s-' + cluster_name + '-%s' % id_generator()
+                )
         gce_instance_names = ','.join(gce_instance_names)
         # Define GCE task
         gce_task = {'gce': {},

src/kargo/common.py

@@ -19,6 +19,7 @@
 import logging
 import shutil
 import os
+import netaddr
 import sys
 import string
 import random
@@ -127,3 +128,16 @@ def run_command(description, cmd):
 
 def id_generator(size=6, chars=string.ascii_lowercase + string.digits):
     return ''.join(random.choice(chars) for _ in range(size))
+
+
+def validate_cidr(cidr, version):
+    """
+    Validates that a CIDR is valid. Returns true if valid, false if
+    not. Version can be "4", "6", None for "IPv4", "IPv6", or "either"
+    respectively.
+    """
+    try:
+        ip = netaddr.IPNetwork(cidr, version=version)
+        return True
+    except (netaddr.core.AddrFormatError, ValueError, TypeError):
+        return False

src/kargo/deploy.py

@@ -27,8 +27,9 @@
 import sys
 import os
 import signal
+import netaddr
 from subprocess import PIPE, STDOUT, Popen, check_output, CalledProcessError
-from kargo.common import get_logger, query_yes_no, run_command, which
+from kargo.common import get_logger, query_yes_no, run_command, which, validate_cidr
 from ansible.utils.display import Display
 display = Display()
 playbook_exec = which('ansible-playbook')
@@ -134,6 +135,25 @@ def coreos_bootstrap(self):
             os.kill(int(os.environ.get('SSH_AGENT_PID')), signal.SIGTERM)
             sys.exit(1)
 
+    def get_subnets(self):
+        '''Check the subnet value and split into 2 distincts subnets'''
+        svc_pfx = 24
+        pods_pfx = 17
+        net = netaddr.IPNetwork(self.options['kube_network'])
+        pfx_error_msg = (
+            "You have to choose a network with a prefix length = 16, "
+            "Please use Ansible options if you need to configure a different netmask."
+        )
+        if net.prefixlen is not 16:
+            display.error(pfx_error_msg)
+            os.kill(int(os.environ.get('SSH_AGENT_PID')), signal.SIGTERM)
+            sys.exit(1)
+        subnets = list(net.subnet(pods_pfx))
+        pods_network, remaining = subnets[0:2]
+        net = netaddr.IPNetwork(remaining)
+        svc_network = list(net.subnet(svc_pfx))[0]
+        return(svc_network, pods_network)
+
     def deploy_kubernetes(self):
         '''
         Run the ansible playbook command
@@ -145,13 +165,30 @@ def deploy_kubernetes(self):
             '-b', '--become-user=root', '-i', self.inventorycfg,
             os.path.join(self.options['kargo_path'], 'cluster.yml')
         ]
+        # Configure the network subnets pods and k8s services
+        if not validate_cidr(self.options['kube_network'], version=4):
+            display.error('Invalid Kubernetes network address')
+            os.kill(int(os.environ.get('SSH_AGENT_PID')), signal.SIGTERM)
+            sys.exit(1)
+        svc_network, pods_network = self.get_subnets()
+        # Add any additionnal Ansible option
         if 'ansible-opts' in self.options.keys():
             cmd = cmd + self.options['ansible-opts'].split(' ')
         for cloud in ['aws', 'gce']:
             if self.options[cloud]:
                 cmd = cmd + ['-e', 'cloud_provider=%s' % cloud]
         if not self.options['coreos']:
             self.check_ping()
+        display.display(
+            'Kubernetes services network : %s (%s IPs)'
+            % (svc_network.cidr, str(svc_network.size.real - 2)),
+            color='bright gray'
+        )
+        display.display(
+            'Pods network : %s (%s IPs)'
+            % (pods_network.cidr, str(pods_network.size.real - 2)),
+            color='bright gray'
+        )
         display.display(' '.join(cmd), color='bright blue')
         if not self.options['assume_yes']:
             if not query_yes_no(