[Linux-ha-dev] [PATCH] gcp-alias.py: manage ip alias

[Helen Koike]

Add a resource agent to manage ip alias in the cluster.

start:
Check if any machine in hostlist has the alias_ip assigned and
disassociate it.
Assign alias_ip to the current machine.

stop:
Disassociate the alias_ip from the current machine.

status/monitor:
Check if alias_ip is assigned with the current machine.

---

This is a port to the following bash script to python:
https://storage.googleapis.com/sapdeploy/pacemaker-gcp/alias

The problem with the bash script is the use of gcloud whose command line
API is not stable.

sudo ./tools/ocf-tester.in -o alias_ip='10.128.1.0/32' -n gcp-alias heartbeat/gcp-alias.py

Beginning tests for heartbeat/gcp-alias.py...
./tools/ocf-tester.in: line 226: cd: @datadir@/resource-agents: No such file or directory
close failed in file object destructor:
sys.excepthook is missing
lost sys.stderr
* rc=1: Your agent produces meta-data which does not conform to ra-api-1.dtd
Tests failed: /home/koike/resource-agents/heartbeat/gcp-alias.py failed 1 tests

The only test failig is the meta-data, but all the agents that I tried
also fails on this. If this is a concern, could you please point me out
to a test which succeeds so I can check what I am doing differently?
The object destructor error is because the test pipe the output to a
command that doesn't read stdin, it can be reproduced by:
python -c "print 'foo'" | ls

This commit can also be viewed at:
https://github.com/collabora-gce/resource-agents/tree/alias

Thanks
---
doc/man/Makefile.am | 1 +
heartbeat/Makefile.am | 1 +
heartbeat/gcp-alias | 310 ++++++++++++++++++++++++++++++++++++++++++
3 files changed, 312 insertions(+)
create mode 100755 heartbeat/gcp-alias

diff --git a/doc/man/Makefile.am b/doc/man/Makefile.am
index 4f766a30..9119aab4 100644
--- a/doc/man/Makefile.am
+++ b/doc/man/Makefile.am
@@ -113,6 +113,7 @@ man_MANS = ocf_heartbeat_AoEtarget.7 \
ocf_heartbeat_fio.7 \
ocf_heartbeat_galera.7 \
ocf_heartbeat_garbd.7 \
+ ocf_heartbeat_gcp-alias.7 \
ocf_heartbeat_gcp-vpc-move-ip.7 \
ocf_heartbeat_iSCSILogicalUnit.7 \
ocf_heartbeat_iSCSITarget.7 \
diff --git a/heartbeat/Makefile.am b/heartbeat/Makefile.am
index 7c3a2e94..942e945a 100644
--- a/heartbeat/Makefile.am
+++ b/heartbeat/Makefile.am
@@ -110,6 +110,7 @@ ocf_SCRIPTS = AoEtarget \
fio \
galera \
garbd \
+ gcp-alias \
gcp-vpc-move-ip \
iSCSILogicalUnit \
iSCSITarget \
diff --git a/heartbeat/gcp-alias b/heartbeat/gcp-alias
new file mode 100755
index 00000000..de8a798f
--- /dev/null
+++ b/heartbeat/gcp-alias
@@ -0,0 +1,310 @@
+#!/usr/bin/env python
+# ---------------------------------------------------------------------
+# Copyright 2016 Google Inc.
+#
+# 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.
+# ---------------------------------------------------------------------
+# Description: Google Cloud Platform - Floating IP Address (Alias)
+# ---------------------------------------------------------------------
+
+import json
+import os
+import platform
+import sys
+import time
+
+import googleapiclient.discovery
+
+if sys.version_info >= (3, 0):
+ # Python 3 imports.
+ import urllib.parse as urlparse
+ import urllib.request as urlrequest
+else:
+ # Python 2 imports.
+ import urllib as urlparse
+ import urllib2 as urlrequest
+
+
+CONN = None
+LOGGER = None
+HOSTNAME = None
+OCF_SUCCESS = 0
+OCF_ERR_GENERIC = 1
+OCF_ERR_CONFIGURED = 6
+OCF_NOT_RUNNING = 7
+METADATA_SERVER = 'http://metadata.google.internal/computeMetadata/v1/'
+METADATA_HEADERS = {'Metadata-Flavor': 'Google'}
+METADATA = \
+'''<?xml version="1.0"?>
+<!DOCTYPE resource-agent SYSTEM "ra-api-1.dtd">
+<resource-agent name="gcp:alias">
+ <version>1.0</version>
+ <longdesc lang="en">Floating IP Address on Google Cloud Platform - Using Alias IP address functionality to attach a secondary IP address to a running instance</longdesc>
+ <shortdesc lang="en">Floating IP Address on Google Cloud Platform</shortdesc>
+ <parameters>
+ <parameter name="hostlist" unique="1" required="1">
+ <longdesc lang="en">List of hosts in the cluster</longdesc>
+ <shortdesc lang="en">Host list</shortdesc>
+ <content type="string" default="" />
+ </parameter>
+ <parameter name="logging" unique="0" required="0">
+ <longdesc lang="en">If enabled (set to true), IP failover logs will be posted to stackdriver logging</longdesc>
+ <shortdesc lang="en">Stackdriver-logging support</shortdesc>
+ <content type="boolean" default="" />
+ </parameter>
+ <parameter name="alias_ip" unique="1" required="1">
+ <longdesc lang="en">IP Address to be added including CIDR. E.g 192.168.0.1/32</longdesc>
+ <shortdesc lang="en">IP Address to be added including CIDR. E.g 192.168.0.1/32</shortdesc>
+ <content type="string" default="" />
+ </parameter>
+ <parameter name="alias_range_name" unique="1" required="0">
+ <longdesc lang="en">Subnet name for the Alias IP2</longdesc>
+ <shortdesc lang="en">Subnet name for the Alias IP</shortdesc>
+ <content type="string" default="" />
+ </parameter>
+ </parameters>
+ <actions>
+ <action name="start" timeout="300" />
+ <action name="stop" timeout="15" />
+ <action name="monitor" timeout="15" interval="60" depth="0" />
+ <action name="meta-data" timeout="15" />
+ </actions>
+</resource-agent>'''
+
+
+def log(severity, msg):
+ print('gcp:alias - %s - %s' % (severity, msg))
+ if LOGGER:
+ msg = '%s %s "%s"' % (
+ HOSTNAME, os.environ.get('OCF_RESOURCE_INSTANCE'), msg)
+ LOGGER.log_text(msg, severity=severity)
+
+
+def log_info(msg):
+ log('INFO', msg)
+
+
+def log_error(msg):
+ log('ERROR', msg)
+
+
+def get_metadata(metadata_key, params=None, timeout=None):
+ """Performs a GET request with the metadata headers.
+
+ Args:
+ metadata_key: string, the metadata to perform a GET request on.
+ params: dictionary, the query parameters in the GET request.
+ timeout: int, timeout in seconds for metadata requests.
+
+ Returns:
+ HTTP response from the GET request.
+
+ Raises:
+ urlerror.HTTPError: raises when the GET request fails.
+ """
+ timeout = timeout or 60
+ metadata_url = os.path.join(METADATA_SERVER, metadata_key)
+ params = urlparse.urlencode(params or {})
+ url = '%s?%s' % (metadata_url, params)
+ request = urlrequest.Request(url, headers=METADATA_HEADERS)
+ request_opener = urlrequest.build_opener(urlrequest.ProxyHandler({}))
+ return request_opener.open(request, timeout=timeout * 1.1).read()
+
+
+def get_instance(project, zone, instance):
+ request = CONN.instances().get(
+ project=project, zone=zone, instance=instance)
+ return request.execute()
+
+
+def get_network_ifaces(project, zone, instance):
+ return get_instance(project, zone, instance)['networkInterfaces']
+
+
+def wait_for_operation(project, zone, operation):
+ while True:
+ result = CONN.zoneOperations().get(
+ project=project,
+ zone=zone,
+ operation=operation['name']).execute()
+
+ if result['status'] == 'DONE':
+ if 'error' in result:
+ raise Exception(result['error'])
+ return
+ time.sleep(1)
+
+
+def set_alias(project, zone, instance, alias, alias_range_name=None):
+ fingerprint = get_network_ifaces(project, zone, instance)[0]['fingerprint']
+ body = {
+ 'aliasIpRanges': [],
+ 'fingerprint': fingerprint
+ }
+ if alias:
+ obj = {'ipCidrRange': alias}
+ if alias_range_name:
+ obj['subnetworkRangeName'] = alias_range_name
+ body['aliasIpRanges'].append(obj)
+
+ request = CONN.instances().updateNetworkInterface(
+ instance=instance, networkInterface='nic0', project=project, zone=zone,
+ body=body)
+ operation = request.execute()
+ wait_for_operation(project, zone, operation)
+
+
+def get_alias(project, zone, instance):
+ iface = get_network_ifaces(project, zone, instance)
+ try:
+ return iface[0]['aliasIpRanges'][0]['ipCidrRange']
+ except KeyError:
+ return ''
+
+
+def get_localhost_alias():
+ net_iface = get_metadata('instance/network-interfaces', {'recursive': True})
+ net_iface = json.loads(net_iface.decode('utf-8'))
+ try:
+ return net_iface[0]['ipAliases'][0]
+ except (KeyError, IndexError):
+ return ''
+
+
+def get_zone(project, instance):
+ request = CONN.zones().list(project=project)
+ while request is not None:
+ response = request.execute()
+ for zone in response['items']:
+ try:
+ get_instance(project, zone['name'], instance)
+ except googleapiclient.errors.HttpError:
+ pass
+ else:
+ return zone['name']
+ request = CONN.zones().list_next(
+ previous_request=request, previous_response=response)
+
+
+def gcp_alias_start(alias):
+ if not alias:
+ sys.exit(OCF_ERR_CONFIGURED)
+ my_alias = get_localhost_alias()
+ my_zone = get_metadata('instance/zone').split('/')[-1]
+ project = get_metadata('project/project-id')
+
+ # If I already have the IP, exit. If it has an alias IP that isn't the VIP,
+ # then remove it
+ if my_alias == alias:
+ log_info(
+ '%s already has %s attached. No action required' % (HOSTNAME, alias))
+ sys.exit(OCF_SUCCESS)
+ elif my_alias:
+ log_info('Removing %s from %s' % (my_alias, HOSTNAME))
+ set_alias(project, my_zone, HOSTNAME, '')
+
+ # Loops through all hosts & remove the alias IP from the host that has it
+ hostlist = os.environ.get('OCF_RESKEY_hostlist', '')
+ hostlist.replace(HOSTNAME, '')
+ for host in hostlist.split():
+ host_zone = get_zone(project, host)
+ host_alias = get_alias(project, host_zone, host)
+ if alias == host_alias:
+ log_info(
+ '%s is attached to %s - Removing all alias IP addresses from %s' %
+ (alias, host, host))
+ set_alias(project, host_zone, host, '')
+ break
+
+ # add alias IP to localhost
+ set_alias(
+ project, my_zone, HOSTNAME, alias,
+ os.environ.get('OCF_RESKEY_alias_range_name'))
+
+ # Check the IP has been added
+ my_alias = get_localhost_alias()
+ if alias == my_alias:
+ log_info('Finished adding %s to %s' % (alias, HOSTNAME))
+ elif my_alias:
+ log_error(
+ 'Failed to add IP. %s has an IP attached but it isn\'t %s' %
+ (HOSTNAME, alias))
+ sys.exit(OCF_ERR_GENERIC)
+ else:
+ log_error('Failed to add IP address %s to %s' % (alias, HOSTNAME))
+ sys.exit(OCF_ERR_GENERIC)
+
+
+def gcp_alias_stop(alias):
+ if not alias:
+ sys.exit(OCF_ERR_CONFIGURED)
+ my_alias = get_localhost_alias()
+ my_zone = get_metadata('instance/zone').split('/')[-1]
+ project = get_metadata('project/project-id')
+
+ if my_alias == alias:
+ log_info('Removing %s from %s' % (my_alias, HOSTNAME))
+ set_alias(project, my_zone, HOSTNAME, '')
+
+
+def gcp_alias_status(alias):
+ if not alias:
+ sys.exit(OCF_ERR_CONFIGURED)
+ my_alias = get_localhost_alias()
+ if alias == my_alias:
+ log_info('%s has the correct IP address attached' % HOSTNAME)
+ else:
+ sys.exit(OCF_NOT_RUNNING)
+
+
+def configure():
+ global CONN
+ global LOGGER
+ global HOSTNAME
+
+ # Populate global vars
+ CONN = googleapiclient.discovery.build('compute', 'v1')
+ HOSTNAME = platform.node()
+
+ # Prepare logging
+ logging_env = os.environ.get('OCF_RESKEY_logging')
+ if logging_env:
+ logging_env = logging_env.lower()
+ if any(x in logging_env for x in ['yes', 'true', 'enabled']):
+
+ try:
+ import google.cloud.logging
+ client = google.cloud.logging.Client()
+ LOGGER = client.logger(HOSTNAME)
+ except ImportError:
+ log_error('Couldn\'t import google.cloud.logging, '
+ 'disabling Stackdriver-logging support')
+
+
+def main():
+ configure()
+
+ alias = os.environ.get('OCF_RESKEY_alias_ip')
+ if 'start' in sys.argv[1]:
+ gcp_alias_start(alias)
+ elif 'stop' in sys.argv[1]:
+ gcp_alias_stop(alias)
+ elif 'status' in sys.argv[1] or 'monitor' in sys.argv[1]:
+ gcp_alias_status(alias)
+ elif 'meta-data' in sys.argv[1]:
+ print(METADATA)
+ else:
+ log_error('gcp:alias - no such function %s' % str(sys.argv[1]))
+
+
+if __name__ == "__main__":
+ main()