More questions coming slightly smiling face Is there a way t Pulumi Community #kubernetes

More questions coming :slightly_smiling_face:. Is ...

wet-noon-14291

05/27/2020, 9:50 AM

More questions coming 🙂. Is there a way to a service name that doesn't add the extra unique characters to the string? Making a POC in .NET and here I would like to set the Uri for the service in the

appsettings.json

file in the frontend app, but that doesn't work since pulumi adds some characters. I guess one way could be to get the name from the environment somehow instead.

wet-noon-14291

05/27/2020, 9:56 AM

To clarify. If I try to deploy services named

frontend

and

backend

. From

frontend

I should now be able to reference the

backend

using

<https://backend>

since they are in the same namespace (at least I think so). With pulumi I have to use

backend-xxxxxx

where I doesn't know what

xxxxx

is before I've deployed

backend

once. For other resources I've seen that you can override the name, but I can't find that for the

Deployment

Service

resources.

ancient-megabyte-79588

05/27/2020, 2:22 PM

It isn't Pulumi that is naming your pods and ReplicaSets that way. It is Kubernetes. Each pod needs to be unique in the cluster, so this is the default (and only) kubernetes behaviour afaik when using Deployments. Your services shouldn't have this kind of unique name in the cluster. This pulumi TypeScript fragment will create a service, attached to pods with the postgresLabels, and give the service the DNS entry in the cluster of

postgres-svc

In the same namespace, you can use the Url or hostname of

postgres-svc

to access that pod, regardless of the pods name.

Copy code

const postgresServiceName = "postgres-svc";
const postgresService = new k8s.core.v1.Service(postgresServiceName, 
    {
        metadata: {
            name: postgresServiceName,
            labels: postgresLabels,
        },
        spec: {
            ports: [{ port: 5432, protocol: "TCP"}],
            selector: postgresLabels,
        },
    }, {provider: k8sProvider});

ancient-megabyte-79588

05/27/2020, 2:24 PM

This is the k8s service resource that is created with that pulumi fragment

ancient-megabyte-79588

05/27/2020, 2:31 PM

If you know the

metadata: { name: "insert-value-here" }

ahead of time, you can put that in your

appsettings.json

you can also override your appsettings.json with an env var that you put in your deployment resource description in Pulumi.

Copy code

const postgresDepName = "postgres-dep";
const postgresDeployment = new k8s.apps.v1.Deployment(postgresDepName, {
    metadata: { 
        name: postgresDepName, 
        labels: postgresLabels
    },
    spec: {
        selector: { matchLabels: postgresLabels },
        replicas: 1,
        revisionHistoryLimit: 2,
        template: {
            metadata: { labels: postgresLabels },
            spec: {
                containers: [{
                    name: "postgres",
                    image: "postgres:alpine",
                    volumeMounts: [{
                        mountPath: "/var/lib/postgresql/data",
                        name: "volume"
                    }],
                    resources: {
                        requests: {
                            cpu: "100m",
                            memory: "100Mi",
                        },
                    },
                    ports: [{ containerPort: 5432 }],
                    env: [
                        {name: "POSTGRES_USER", value: "admin"},
                        {name: "POSTGRES_PASSWORD", value: "P@ssw0rd!"},
                        {name: "POSTGRES_DB", value: "identity"},
                        {name: "PGDATA", value: "/mnt/data/pgdata"}
                    ]
                }],
                volumes:[{
                    name: "volume",
                    persistentVolumeClaim: {
                        claimName: postgresPVClaimName
                    }
                }]
            },
        },
    },
}, {provider: k8sProvider});

ancient-megabyte-79588

05/27/2020, 2:31 PM

Note the

env: []

section in the container spec

ancient-megabyte-79588

05/27/2020, 2:31 PM

You can see this code here: https://westerndevs.com/kubernetes/kubernetes-my-journey-part-7b/

creamy-potato-29402

05/27/2020, 3:12 PM

pulumi does add a suffix to resources. this is so that if you change an immutable field it can orchestrate a replacement. to avoid this just manually specify .metadata.name.

gorgeous-egg-16927

05/27/2020, 3:12 PM

If you’re referring to the random suffix on the resource name, see https://www.pulumi.com/docs/intro/concepts/programming-model/#autonaming for more details. Short answer is that it won’t be autonamed if specify

.metadata.name

of any k8s resource

wet-noon-14291

05/28/2020, 6:53 AM

Got it, thanks.

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