- Get all GCP instance data like name, status, internal IP.
- Update GCP Cloud DNS (delete and add from Instances)
- Python + GKE – Get the pods!
Get all GCP instance data like name, status, internal IP.
# Credentials from specific GCP SA
import os
os.environ["GOOGLE_APPLICATION_CREDENTIALS"]="majestic-layout-340900-668e5ad81962.json"
# Set variable `compute` to connect to GCP compute engine
import googleapiclient.discovery
compute = googleapiclient.discovery.build('compute', 'v1')
# Set GCP project and zone
project_s = 'majestic-layout-340900'
# Disabled - This is for specific zone only .list()
# zone_s = 'us-central1-c'
# Set var `result` to get the data array of all GCP instances on a zpecific zone
# https://developers.google.com/resources/api-libraries/documentation/compute/v1/python/latest/compute_v1.instances.html#list
# result = compute.instances().list(project=project_s, zone=*).execute()
# To get all instances for all regions and zones
# https://developers.google.com/resources/api-libraries/documentation/compute/v1/python/latest/compute_v1.instances.html#list
result = compute.instances().aggregatedList(project=project_s).execute()
# Create class to get GCP instances
class gcp_instances:
# Get all instances function
def get_instances(self):
for _, labels_scoped_list in result['items'].items():
# Loop all values for the key 'instances' only
if 'instances' in labels_scoped_list:
for entry in labels_scoped_list['instances']:
# Print instance name, status and internal IP
instance_name = entry['name']
instance_status = entry['status']
instance_int_ip = entry['networkInterfaces'][0]['networkIP']
print(instance_name, ':', instance_int_ip, ':', instance_status)
# Call the function `get_instances` inside the class `gcp_instances`
class_gcp_instances = gcp_instances()
class_gcp_instances.get_instances()
Update GCP Cloud DNS (delete and add from Instances)
The code below will delete all DNS A records from the GCP Cloud DNS zone (the first zone), get the VM Instances details (name and its internal IP), then add each of those to the Cloud DNS A records.
# Import GCP client library to use compute instance functions
import googleapiclient.discovery
# Setup GCP Credentials
from google.auth import compute_engine
# Import GCP client library to use compute instance functions
import googleapiclient.discovery
class update_dns_a_records_from_instances():
def __init__(self):
# Default values for GCP Project
self.project= None
def setup(self):
# Fetch the GCP Project from the environment - This is currently not working!
# self.project = os.environ.get('GCP_PROJECT')
# Set GCP project and zone
self.project = 'majestic-layout-340900'
# Set up the Google Cloud Compute client
credentials = compute_engine.Credentials()
self.computeadmin = googleapiclient.discovery.build('compute', 'v1', credentials=credentials, cache_discovery=False)
# Setup Google Clouid DNS client
self.dns_service = googleapiclient.discovery.build('dns', 'v1', credentials=credentials)
# Get the first Zone.
# Use this if you have one zone only!
# Otherwise, enter a static zone name manually like below:
# self.zone_name = "zone1"
get_zone_request = self.dns_service.managedZones().list(project=self.project)
get_zone_response = get_zone_request.execute()
self.zone_name = get_zone_response['managedZones'][0]['name']
# Get DNS name
dns_name_request = self.dns_service.managedZones().get(project=self.project, managedZone=self.zone_name)
dns_name_response = dns_name_request.execute()
self.dns_name = dns_name_response['dnsName']
def update_dns(self):
# List all DNS A records then delete
list_dns_request = self.dns_service.resourceRecordSets().list(project=self.project, managedZone=self.zone_name)
list_dns_response = list_dns_request.execute()
# print("Gather all DNS A records for deletion..")
for dns_list in list_dns_response['rrsets']:
if dns_list['type'] == "A":
current_dns_name = dns_list['name']
current_dns_type = dns_list['type']
current_dns_rrdata = dns_list['rrdatas']
current_dns_ttl = dns_list['ttl']
# Generate deletion var list for each dns entry
delete_dns = {
"deletions": [
{
"name": current_dns_name,
"type": current_dns_type,
"ttl": current_dns_ttl,
"rrdata": current_dns_rrdata
}
]
}
# Print for debug - ex output: instance-1.zone1.test. A ['10.128.0.35'] 300
# print(current_dns_name, current_dns_type, current_dns_rrdata, current_dns_ttl)
# Delete each DNS entry from this loop
del_dns_request = self.dns_service.changes().create(project=self.project, managedZone=self.zone_name, body=delete_dns)
del_dns_response = del_dns_request.execute()
# Request to get all instances (500 max results but this will loop via aggregatedList_next to get all instances)
request = self.computeadmin.instances().aggregatedList(project=self.project, includeAllScopes=True)
while request is not None:
response = request.execute()
# Run the loop - fetch all instances
for _, list_of_instances in response['items'].items():
# Check if we have instances returned
if 'instances' in list_of_instances:
# Loop through the instances dict
for entry in list_of_instances['instances']:
instance_name = entry['name']
instance_status = entry['status']
instance_int_ip = entry['networkInterfaces'][0]['networkIP']
# Add DNS entry A record for each instances internal IP and its instance names
add_dns = {
"additions": [
{
"name": instance_name + "." + self.dns_name,
"type": "A",
"ttl": 300,
"rrdata": [
instance_int_ip
]
}
]
}
request = self.dns_service.changes().create(project=self.project, managedZone=self.zone_name, body=add_dns)
response = request.execute()
request = self.computeadmin.instances().aggregatedList_next(previous_request=request,
previous_response=response)
def run(self):
# Set up our environment.
self.setup()
# RUN update_dns() fuction
update_dns = self.update_dns()
def main(request): # pragma: no cover
try:
check = update_dns_a_records_from_instances()
check.run()
except Exception as e:
print(e)
# Simplify running in a development environment.
if __name__ == "__main__": # pragma: no cover
main(None)
Python + GKE – Get the pods!
requirements.txt
kubernetes
google-api-python-client
google-cloud-container
python-hostsimport base64
import google.auth.transport.requests
from google.oauth2 import service_account
from google.cloud.container_v1 import ClusterManagerClient
from kubernetes import client
from python_hosts.hosts import Hosts, HostsEntry
class gke:
def get_clusters(self):
print("Get clusters!")
project_id = 'majestic-layout-340900'
zone = "us-central1-c"
cluster_id = "cluster-1"
# Use a service account configured in GCP console,
# authenticating with a JSON key
credentials = service_account.Credentials \
.from_service_account_file('majestic-layout-340900-668e5ad81962.json')
# Get cluster details
cluster_manager_client = ClusterManagerClient(credentials=credentials)
cluster = cluster_manager_client.get_cluster(
project_id=project_id, zone=zone,
cluster_id=cluster_id)
# Save cluster certificate for SSL verification
cert = base64.b64decode(cluster.master_auth.cluster_ca_certificate)
cert_filename = 'cluster_ca_cert'
cert_file = open(cert_filename, 'wb')
cert_file.write(cert)
cert_file.close()
# Configure hostname for SSL verification
hosts = Hosts()
hosts.add([HostsEntry(
entry_type='ipv4',
address=cluster.endpoint, names=['kubernetes'])])
hosts.write()
# Get a token with the scopes required by GKE
kubeconfig_creds = credentials.with_scopes(
['https://www.googleapis.com/auth/cloud-platform',
'https://www.googleapis.com/auth/userinfo.email'])
auth_req = google.auth.transport.requests.Request()
kubeconfig_creds.refresh(auth_req)
configuration = client.Configuration()
configuration.host = "https://kubernetes"
configuration.ssl_ca_cert = cert_filename
kubeconfig_creds.apply(configuration.api_key)
client.Configuration.set_default(configuration)
v1 = client.CoreV1Api()
print("Listing pods with their IPs:")
pods = v1.list_pod_for_all_namespaces(watch=False)
for i in pods.items:
print("%s\t%s\t%s" % (i.status.pod_ip, i.metadata.namespace, i.metadata.name))
run = gke()
run.get_clusters()