koff

koff is a command-line tool that processes Kubernetes yaml|json manifests or etcd database snapshot and returns their appropriate tabular format, as well as yaml or json.

What?

It allows you to process Kubernetes resources in yaml or json format, from either file or piped input or etcd snapshot file. It reads input, performs the specific filter operations based on the flags and arguments (if provided), and writes the output in either tabular (as default), json or yaml format.

Why?

Helpful in conjunction with kubectl to take a "snapshot" of specific resources at that specific point in time and parse the same later on.

How?

• Via piped input:

  $ cat resources.yaml | koff get pod/postgresql-1-2gxpm svc/postgresql
  NAME                     READY   STATUS    RESTARTS   AGE
  pod/postgresql-1-2gxpm   1/1     Running   0          15m
  
  NAME                 TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)    AGE
  service/postgresql   ClusterIP   172.30.58.223   <none>        5432/TCP   16m
  

• Referencing the file to use via koff use <resources>.yaml before executing koff:

  $ koff use resources.yaml
  $ koff get pod/postgresql-1-2gxpm svc/postgresql
  NAME                     READY   STATUS    RESTARTS   AGE
  pod/postgresql-1-2gxpm   1/1     Running   0          15m
  
  NAME                 TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)    AGE
  service/postgresql   ClusterIP   172.30.58.223   <none>        5432/TCP   16m
  

• Using an etcd snapshot to get the Kubernetes object contained in it (the only requirement is that the database snapshot needs to have .db suffix):

  $ koff use etcd_snap.db
  
  $ koff get po,svc -n openshift-etcd
  NAME                                                READY   STATUS      RESTARTS   AGE
  pod/etcd-guard-labocp417-jh6n2-master-0          1/1     Running     0          1d
  pod/etcd-guard-labocp417-jh6n2-master-1          1/1     Running     0          1d
  pod/etcd-guard-labocp417-jh6n2-master-2          1/1     Running     0          1d
  pod/etcd-labocp417-jh6n2-master-0                4/4     Running     0          1d
  pod/etcd-labocp417-jh6n2-master-1                4/4     Running     0          1d
  pod/etcd-labocp417-jh6n2-master-2                4/4     Running     0          1d
  pod/installer-8-labocp417-jh6n2-master-2         0/1     Completed   0          1d
  pod/revision-pruner-7-labocp417-jh6n2-master-0   0/1     Completed   0          1d
  pod/revision-pruner-7-labocp417-jh6n2-master-1   0/1     Completed   0          1d
  pod/revision-pruner-7-labocp417-jh6n2-master-2   0/1     Completed   0          1d
  pod/revision-pruner-8-labocp417-jh6n2-master-0   0/1     Completed   0          1d
  pod/revision-pruner-8-labocp417-jh6n2-master-1   0/1     Completed   0          1d
  pod/revision-pruner-8-labocp417-jh6n2-master-2   0/1     Completed   0          1d
  
  NAME           TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)             AGE
  service/etcd   ClusterIP   172.30.24.145   <none>        2379/TCP,9979/TCP   1d
  

Installation

Using go

go install github.com/gmeghnag/koff 

Download the latest binary

OS=Linux        # or Darwin
curl -sL "https://github.com/gmeghnag/koff/releases/latest/download/koff_${OS}_x86_64.tar.gz" | tar xzf - koff
chmod +x ./koff

Build from source

$ git clone https://github.com/gmeghnag/koff.git
$ cd koff/
$ go install

Upgrade

It's possible to upgrade the tool to the latest version by running koff upgrade --to=latest