This charm acts as a proxy to GCP and provides an interface to apply a certain set of changes via roles, profiles, and tags to the instances of the applications that are related to this charm.
When on GCP, this charm can be deployed, granted trust via Juju to access GCP, and then related to an application that supports the interface.
For example, Charmed Kubernetes has support for this, and can be deployed with the following bundle overlay:
applications: gcp-integrator: charm: cs:~containers/gcp-integrator num_units: 1 relations: - ['gcp-integrator', 'kubernetes-master'] - ['gcp-integrator', 'kubernetes-worker']
Then deploy Charmed Kubernetes using this overlay:
juju deploy cs:charmed-kubernetes --overlay ./k8s-gcp-overlay.yaml
The charm then needs to be granted access to credentials that it can use to setup integrations. Using Juju 2.4 or later, you can easily grant access to the credentials used deploy the integrator itself:
juju trust gcp-integrator
To deploy with earlier versions of Juju, or if you wish to provide it different
credentials, you will need to provide the cloud credentials via the
charm config options.
Note: The credentials used must be enabled to use the API to inspect the instances connecting to it, enable a service account for those instances, assign roles to those instances, and create custom roles.
Resource Usage Note
By relating to this charm, other charms can directly allocate resources, such as PersistentDisk volumes and Load Balancers, which could lead to cloud charges and count against quotas. Because these resources are not managed by Juju, they will not be automatically deleted when the models or applications are destroyed, nor will they show up in Juju's status or GUI. It is therefore up to the operator to manually delete these resources when they are no longer needed, using the Google Cloud console or API.
Following are some examples using GCP integration with Charmed Kubernetes.
Creating a pod with a PersistentDisk-backed volume
This script creates a busybox pod with a persistent volume claim backed by GCE's PersistentDisk.
#!/bin/bash # create a storage class using the `kubernetes.io/gce-pd` provisioner kubectl create -f - <<EOY apiVersion: storage.k8s.io/v1 kind: StorageClass metadata: name: gce-standard provisioner: kubernetes.io/gce-pd parameters: type: pd-standard EOY # create a persistent volume claim using that storage class kubectl create -f - <<EOY kind: PersistentVolumeClaim apiVersion: v1 metadata: name: testclaim spec: accessModes: - ReadWriteOnce resources: requests: storage: 100Mi storageClassName: gce-standard EOY # create the busybox pod with a volume using that PVC: kubectl create -f - <<EOY apiVersion: v1 kind: Pod metadata: name: busybox namespace: default spec: containers: - image: busybox command: - sleep - "3600" imagePullPolicy: IfNotPresent name: busybox volumeMounts: - mountPath: "/pv" name: testvolume restartPolicy: Always volumes: - name: testvolume persistentVolumeClaim: claimName: testclaim EOY
Creating a service with a GCE load-balancer
The following script starts the hello-world pod behind a GCE-backed load-balancer.
#!/bin/bash kubectl run hello-world --replicas=5 --labels="run=load-balancer-example" --image=gcr.io/google-samples/node-hello:1.0 --port=8080 kubectl expose deployment hello-world --type=LoadBalancer --name=hello watch kubectl get svc -o wide --selector=run=load-balancer-example
|snap_proxy||string||DEPRECATED. Use snap-http-proxy and snap-https-proxy model configuration settings. HTTP/HTTPS web proxy for Snappy to use when accessing the snap store.|
|snap_proxy_url||string||DEPRECATED. Use snap-store-proxy model configuration setting. The address of a Snap Store Proxy to use for snaps e.g. http://snap-proxy.example.com|
The base64-encoded contents of an GCP credentials JSON file.
This can be used from bundles with 'include-base64://' (see https://jujucharms.com/docs/stable/charms-bundles#setting-charm-configurations-options-in-a-bundle), or from the command-line with 'juju config gcp credentials="$(base64 /path/to/file)"'.
It is strongly recommended that you use 'juju trust' instead, if available.
How often snapd handles updates for installed snaps. The default (an empty string) is 4x per day. Set to "max" to check once per month based on the charm deployment date. You may also set a custom string as described in the 'refresh.timer' section here: https://forum.snapcraft.io/t/system-options/87
You can run an action with the following
juju run-action gcp-integrator ACTION [parameters] [--wait]
List all service accounts created by this charm (i.e., with the prefix `juju-gcp-`), both active and unknown (i.e., created by another instance of this charm or no longer in use).
Purge service accounts created by this charm (i.e., with the prefix `juju-gcp-`) that are no longer in active use by this charm. Be careful! There is no way for this action to determine if these accounts are in use elsewhere, such as in another model. Running this action while there are accounts in use elsewhere will likely break the applications depending on those accounts.