KDeploy

kdeploy, a tool that let's you deploy kubewares in your kubernetes cluster.

You can download kdeploy binary for

• Linux
• OS X
• Windows

Drop kdeploy somewhere in your $PATH and grant execute permissions

$ curl -o /usr/local/bin/kdeploy  https://drone.io/github.com/flexiant/kdeploy/files/_output/kdeploy.x64.darwin
$ chmod +x /usr/local/bin/kdeploy

What is a kubeware?

A kubeware is a combination of regular kubernetes API objects represented as yaml files, and a metadata file that contains the description and attributes for the application or service.

• yaml files are actual kubernetes files templates, that use moustache.
• metadata file contains basic metadata about the kubeware, references to all files that comprise the kubeware, and a list of managed attributes.
• attributes.json file that contains the values for those attributes in yaml files.

I'll give it a try, how do I create a kubeware?

Edit an existing kubernetes example, guestbook if you will, and think of all those values that you'd like to modify for each environment. Let's say that when you deploy to a local vagrant cluster, you are good with ServiceType set to ClusterIP, and that when you deploy to an environment that supports load balancing (like Flexiant Concerto) you want the ServiceType set to LoadBalancer.

You might also want to change values for the initial number of replicas, image names and tags, labels, ports, IPs, ... we can extract those values to an attribute file, and use kdeploy to combine the attribute file with kubernetes API files.

Create Kubeware template

Hands on, edit a replication controller API file, and search for the replicas tag

spec:
  # this replicas value is default
  # modify it according to your case
  replicas: 2

Now substitute the number of replicas with a moustache placeholder.

spec:
  # this replicas value is default
  # modify it according to your case
  replicas: {{ $number_of_replicas }}

Modify other parameters and save the kubernetes API file. This template should remain untouched unless you change your application architecture.

Create Metadata

We also need a metadata.yaml that serves as index for our kubeware and allow us to set default attributes.

Let's start adding some authoring metadata attributes:

• name name of the Kubeware.
• maintainername of maintainer company or person(s).
• email contact email.
• description Kubeware description.
• version version of Kubeware will be used when deploying upgrades.
• source URL where Kubeware is to be found. Currently kdeploy only supports github.
• issues URL for the issue tracker.

name: "Guestbook"
maintainer: "Flexiant Ltd."
email: "contact@flexiant.com"
description: "Installs/Configures Guestbook Example via KDeploy"
version: "0.0.1"
source: "https://github.com/flexiant/kubeware-guestbook"
issues: "https://github.com/flexiant/kubeware-guestbook/issues"

Next, reference all kubernetes files in this Kubeware. Add service under svc and resource controllers under rc:

svc:
  redis-master: "redis-master-service.yaml"
  redis-slave: "redis-slave-service.yaml"
  frontend: "frontend-service.yaml"

rc:
  redis-master: "redis-master-controller.yaml"
  redis-slave: "redis-slave-controller.yaml"
  frontend: "frontend-controller.yaml"

Finally, create an attributes section, and add those attributes that need description, defaults, or required.

• Not all attributes must appear in this section. If an attribute doesn't appear in this section, it won't have a default, be required, nor have a description
• If an attribute is required and is not informed, or hasn't a default, kdeploy will return an error.

attributes:
  svc:
    frontend:
      balancer:
        description: "Defines how we want to expose the Frontend Service"
        default: LoadBalancer
        required: true
      port:
        description: "Defines expose port for the Frontend Service"
        default: 80
        required: true
    redis-master:
      port:
        description: "Defines expose port for the redis master service"
        default: 6379
        required: true
...

Create Attributes file

Attributes files are JSON files that customize variables for each environment. Let's create the "poor man's" scenario for the , where we only one redis slave replica running.

{
  "rc":{
    "redis-slave":{
      "number":1
    ...
    }
  }
}

Also, create a different "rich man's" JSON file that runs 10 redis slave replicas.

{
  "rc":{
    "redis-slave":{
      "number":10
    }
  }
}

That's it. You can use the Kuberware template and overwrite default values using your JSON of choice.

How do I use kdeploy?

Download kdeploy and create a kubernetes configuration file, like the ones used by kubectl, using client certificates. If kubectl is working, kdeploy is working too.

Upload the kubeware to a folder in github (we only support github for now)

To deploy the application with a set of attributes use

kdeploy deploy --kubeware https://github.com/flexiant/kubeware-guestbook --attribute poorman.json --namespace poorman

That will run a full application in kubernetes, using your selection of attributes. You can use kubectlto check that the pods state, but we found useful adding listing and deleting behavior to kdeploy, so you don't have to switch tool.

To list all kubewares

kdeploy list --all

To delete a kubeware

kdeploy delete --kubeware https://github.com/flexiant/kubeware-guestbook --namespace poorman

What else can I do with kdeploy

kdeploy was born as an internal tool to save time deploying k8s applications at Flexiant. We are planning to bring in some new features to kdeploy, as long as we keep it simple and agile.

Contributors are welcome anytime.