2017-02-08 11:50:26 +01:00
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KonTemplate - A simple Kubernetes templater
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===========================================
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2017-02-08 13:03:06 +01:00
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[](https://travis-ci.org/tazjin/kontemplate)
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2017-02-08 11:50:26 +01:00
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I made this tool out of frustration with the available ways to template Kubernetes resource files. All I want out of
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such a tool is a way to specify lots of resources with placeholders that get filled in with specific values, based on
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which context (i.e. k8s cluster) is specified.
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## Overview
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KonTemplate lets you describe resources as you normally would in a simple folder structure:
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```
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.
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2017-02-08 13:15:36 +01:00
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├── prod-cluster.yaml
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2017-02-08 11:50:26 +01:00
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└── some-api
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├── deployment.yaml
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└── service.yaml
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```
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This example has all resources belonging to `some-api` (no file naming conventions enforced at all!) in the `some-api`
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folder and the configuration for the cluster `prod-cluster` in the corresponding file.
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2017-02-08 13:15:36 +01:00
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Lets take a short look at `prod-cluster.yaml`:
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```yaml
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---
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context: k8s.prod.mydomain.com
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global:
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globalVar: lizards
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include:
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- name: some-api
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values:
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version: 1.0-0e6884d
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importantFeature: true
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apiPort: 4567
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2017-02-08 11:50:26 +01:00
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```
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Those values are then templated into the resource files of `some-api`.
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2017-02-08 13:53:46 +01:00
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## Installation
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Assuming you have Go configured correctly, you can simply `go get github.com/tazjin/kontemplate/...`.
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2017-02-08 11:50:26 +01:00
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## Usage
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2017-02-08 13:53:46 +01:00
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You must have `kubectl` installed to use KonTemplate effectively.
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2017-02-08 14:07:56 +01:00
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```
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NAME:
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kontemplate run - Interpolate and print templates
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USAGE:
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kontemplate run [command options] [arguments...]
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OPTIONS:
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--file value, -f value Cluster configuration file to use
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--limit value, -l value Limit templating to certain resource sets
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```
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2017-02-08 13:53:46 +01:00
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At the moment KonTemplate will simply output the templated Kubernetes resource files, which can
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then be piped into `kubectl`:
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```
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# Look at output and check to see if it's correct ...
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kontemplate run -f example/prod-cluster.yaml -l some-api
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# ... if it is, go ahead and apply it
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kontemplate run -f example/prod-cluster.yaml -l some-api | kubectl apply -f -
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# That's it!
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```
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