#!/usr/bin/env python # Licensed to the Apache Software Foundation (ASF) under one or more # contributor license agreements. See the NOTICE file distributed with # this work for additional information regarding copyright ownership. # The ASF licenses this file to You 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. # This example performs several tasks on Google Compute Engine and the GCE # Load Balancer. It can be run directly or can be imported into an # interactive python session. This can also serve as an integration test for # the GCE Load Balancer Driver. # # To run interactively: # - Make sure you have valid values in secrets.py # (For more information about setting up your credentials, see the # libcloud/common/google.py docstring) # - Run 'python' in this directory, then: # import gce_lb_demo # gcelb = gce_lb_demo.get_gcelb_driver() # gcelb.list_balancers() # etc. # - Or, to run the full demo from the interactive python shell: # import gce_lb_demo # gce_lb_demo.CLEANUP = False # optional # gce_lb_demo.MAX_NODES = 4 # optional # gce_lb_demo.DATACENTER = 'us-central1-a' # optional # gce_lb_demo.main() import os.path import sys import time try: import secrets except ImportError: print('"demos/secrets.py" not found.\n\n' 'Please copy secrets.py-dist to secrets.py and update the GCE* ' 'values with appropriate authentication information.\n' 'Additional information about setting these values can be found ' 'in the docstring for:\n' 'libcloud/common/google.py\n') sys.exit(1) # Add parent dir of this file's dir to sys.path (OS-agnostically) sys.path.append(os.path.normpath(os.path.join(os.path.dirname(__file__), os.path.pardir))) from libcloud.utils.py3 import PY3 if PY3: import urllib.request as url_req else: import urllib2 as url_req # This demo uses both the Compute driver and the LoadBalancer driver from libcloud.compute.types import Provider from libcloud.compute.providers import get_driver from libcloud.loadbalancer.types import Provider as Provider_lb from libcloud.loadbalancer.providers import get_driver as get_driver_lb # String that all resource names created by the demo will start with # WARNING: Any resource that has a matching name will be destroyed. DEMO_BASE_NAME = 'libcloud-lb-demo' # Datacenter to create resources in DATACENTER = 'us-central1-a' # Clean up resources at the end (can be set to false in order to # inspect resources at the end of the run). Resources will be cleaned # at the beginning regardless. CLEANUP = True args = getattr(secrets, 'GCE_PARAMS', ()) kwargs = getattr(secrets, 'GCE_KEYWORD_PARAMS', {}) # Add datacenter to kwargs for Python 2.5 compatibility kwargs = kwargs.copy() kwargs['datacenter'] = DATACENTER # ==== HELPER FUNCTIONS ==== def get_gce_driver(): driver = get_driver(Provider.GCE)(*args, **kwargs) return driver def get_gcelb_driver(gce_driver=None): # The GCE Load Balancer driver uses the GCE Compute driver for all of its # API calls. You can either provide the driver directly, or provide the # same authentication information so the LB driver can get its own # Compute driver. if gce_driver: driver = get_driver_lb(Provider_lb.GCE)(gce_driver=gce_driver) else: driver = get_driver_lb(Provider_lb.GCE)(*args, **kwargs) return driver def display(title, resource_list): """ Display a list of resources. :param title: String to be printed at the heading of the list. :type title: ``str`` :param resource_list: List of resources to display :type resource_list: Any ``object`` with a C{name} attribute """ print('%s:' % title) for item in resource_list[:10]: print(' %s' % item.name) def clean_up(gce, base_name, node_list=None, resource_list=None): """ Destroy all resources that have a name beginning with 'base_name'. :param base_name: String with the first part of the name of resources to destroy :type base_name: ``str`` :keyword node_list: List of nodes to consider for deletion :type node_list: ``list`` of :class:`Node` :keyword resource_list: List of resources to consider for deletion :type resource_list: ``list`` of I{Resource Objects} """ if node_list is None: node_list = [] if resource_list is None: resource_list = [] # Use ex_destroy_multiple_nodes to destroy nodes del_nodes = [] for node in node_list: if node.name.startswith(base_name): del_nodes.append(node) result = gce.ex_destroy_multiple_nodes(del_nodes) for i, success in enumerate(result): if success: print(' Deleted %s' % del_nodes[i].name) else: print(' Failed to delete %s' % del_nodes[i].name) # Destroy everything else with just the destroy method for resource in resource_list: if resource.name.startswith(base_name): if resource.destroy(): print(' Deleted %s' % resource.name) else: print(' Failed to Delete %s' % resource.name) # ==== DEMO CODE STARTS HERE ==== def main(): gce = get_gce_driver() gcelb = get_gcelb_driver(gce) # Existing Balancers balancers = gcelb.list_balancers() display('Load Balancers', balancers) # Protocols protocols = gcelb.list_protocols() print('Protocols:') for p in protocols: print(' %s' % p) # Healthchecks healthchecks = gcelb.ex_list_healthchecks() display('Health Checks', healthchecks) # This demo is based on the GCE Load Balancing Quickstart described here: # https://developers.google.com/compute/docs/load-balancing/lb-quickstart # == Clean-up and existing demo resources == all_nodes = gce.list_nodes(ex_zone='all') firewalls = gce.ex_list_firewalls() print('Cleaning up any "%s" resources:' % DEMO_BASE_NAME) clean_up(gce, DEMO_BASE_NAME, all_nodes, balancers + healthchecks + firewalls) # == Create 3 nodes to balance between == startup_script = ('apt-get -y update && ' 'apt-get -y install apache2 && ' 'hostname > /var/www/index.html') tag = '%s-www' % DEMO_BASE_NAME base_name = '%s-www' % DEMO_BASE_NAME image = gce.ex_get_image('debian-7') size = gce.ex_get_size('n1-standard-1') number = 3 metadata = {'items': [{'key': 'startup-script', 'value': startup_script}]} lb_nodes = gce.ex_create_multiple_nodes(base_name, size, image, number, ex_tags=[tag], ex_metadata=metadata, ignore_errors=False) display('Created Nodes', lb_nodes) # == Create a Firewall for instances == print('Creating a Firewall:') name = '%s-firewall' % DEMO_BASE_NAME allowed = [{'IPProtocol': 'tcp', 'ports': ['80']}] firewall = gce.ex_create_firewall(name, allowed, source_tags=[tag]) print(' Firewall %s created' % firewall.name) # == Create a Health Check == print('Creating a HealthCheck:') name = '%s-healthcheck' % DEMO_BASE_NAME # These are all the default values, but listed here as an example. To # create a healthcheck with the defaults, only name is required. hc = gcelb.ex_create_healthcheck(name, host=None, path='/', port='80', interval=5, timeout=5, unhealthy_threshold=2, healthy_threshold=2) print(' Healthcheck %s created' % hc.name) # == Create Load Balancer == print('Creating Load Balancer') name = '%s-lb' % DEMO_BASE_NAME port = 80 protocol = 'tcp' algorithm = None members = lb_nodes[:2] # Only attach the first two initially healthchecks = [hc] balancer = gcelb.create_balancer(name, port, protocol, algorithm, members, ex_healthchecks=healthchecks) print(' Load Balancer %s created' % balancer.name) # == Attach third Node == print('Attaching additional node to Load Balancer:') member = balancer.attach_compute_node(lb_nodes[2]) print(' Attached %s to %s' % (member.id, balancer.name)) # == Show Balancer Members == members = balancer.list_members() print('Load Balancer Members:') for member in members: print(' ID: %s IP: %s' % (member.id, member.ip)) # == Remove a Member == print('Removing a Member:') detached = members[0] detach = balancer.detach_member(detached) if detach: print(' Member %s detached from %s' % (detached.id, balancer.name)) # == Show Updated Balancer Members == members = balancer.list_members() print('Updated Load Balancer Members:') for member in members: print(' ID: %s IP: %s' % (member.id, member.ip)) # == Reattach Member == print('Reattaching Member:') member = balancer.attach_member(detached) print(' Member %s attached to %s' % (member.id, balancer.name)) # == Test Load Balancer by connecting to it multiple times == print('Sleeping for 10 seconds to stabilize the balancer...') time.sleep(10) rounds = 200 url = 'http://%s/' % balancer.ip line_length = 75 print('Connecting to %s %s times:' % (url, rounds)) for x in range(rounds): response = url_req.urlopen(url) if PY3: output = str(response.read(), encoding='utf-8').strip() else: output = response.read().strip() if 'www-001' in output: padded_output = output.center(line_length) elif 'www-002' in output: padded_output = output.rjust(line_length) else: padded_output = output.ljust(line_length) sys.stdout.write('\r%s' % padded_output) sys.stdout.flush() print('') if CLEANUP: balancers = gcelb.list_balancers() healthchecks = gcelb.ex_list_healthchecks() nodes = gce.list_nodes(ex_zone='all') firewalls = gce.ex_list_firewalls() print('Cleaning up %s resources created.' % DEMO_BASE_NAME) clean_up(gce, DEMO_BASE_NAME, nodes, balancers + healthchecks + firewalls) if __name__ == '__main__': main()