GitHub - alfiankan/crab-config-files-templating: Dynamic configuration file templating tool for kubernetes manifest or general configuration files (original) (raw)

Crab 🦀

Dynamic configuration file templating tool for kubernetes manifest or general configuration files

How to install

Download according to your computer architecture at release page go to release page

Extract using command like :

tar -xzf crab-cli-v0.1.0-darwin-amd64.tar.gz -C crab

Move to /usr/local/bin (Optional) :

cp crab/crab /usr/local/bin

Then check crab cli working properly :

Build From Source

• clone this repository
• make sure you have go version 18
• run make build

How to use

basic command fromat :

crab -f -r -o

Flags :

Case 1 Standart replace

First add {{replacableName}} to your file :

apiVersion: v1 kind: Service metadata: name: nginx namespace: {{namespace}} spec: ports: - targetPort: 80 name: nginxhttp port: {{exposePort}}

crab cli will replace {{replacableName}} as the key, based on the example above :

• {{namespace}}
• {{exposePort}}

then run crab command :

crab -f inputfile.yaml -r namespace=production -r exposePort=8081

yes you can override multiple key values ✔️

write output to another file add -o flag:

crab -f inputfile.yaml -r namespace=production -r exposePort=8081 -o result.yaml

to make verbose add -v flag:

crab -f inputfile.yaml -r namespace=production -r exposePort=8081 -o result.yaml -v

verbose output :

[REPLACED] from namespace to production [REPLACED] from exposePort to 8081 [DONE] Crab output result at result.yaml

the result will be :

apiVersion: v1 kind: Service metadata: name: nginx namespace: production spec: ports: - targetPort: 80 name: nginxhttp port: 8081

Click to watch the demo :

Youtube demo video :

• go to youtube

Case 2 Quotes replace

sometimes your config file needs string quotes, (like for env vars or connection string):

template file example :

apiVersion: v1 kind: Service metadata: name: nginx namespace: {{namespace}} spec: ports: - targetPort: 80 name: nginxhttp port: {{exposePort}}

let's say we need a quote in the namespace :

crab -f inputfile.yaml -q namespace=production -r exposePort=8081 -o result.yaml -v

yass you can simultaneously Replace multiple key values with quotes or not ✔️

result will be :

apiVersion: v1 kind: Service metadata: name: nginx namespace: "production" spec: ports: - targetPort: 80 name: nginxhttp port: 8081

Sample Github Action

name: Demo deployment using crab

on: workflow_dispatch:

jobs: crab-manifest: runs-on: ubuntu-latest steps: - uses: actions/checkout@v3 - name: mock job run: pwd

deploy-test: runs-on: ubuntu-latest needs: crab-manifest steps: - uses: actions/checkout@v3 - name: install crab cli run: wget -c https://github.com/alfiankan/crab-config-files-templating/releases/download/v1.0.5/crab-v1.0.5-linux-amd64.tar.gz -O - | tar -xz crab - name: recreate deployment manifest on test run: | ./crab -f example/manifest/nginx.yaml
-r namespace=test
-r publishPort=8000
-q portName=test-server
-o nginx-test.yaml
-v - name: view manifest run: cat nginx-test.yaml

deploy-production: runs-on: ubuntu-latest needs: crab-manifest steps: - uses: actions/checkout@v3 - name: install crab cli run: wget -c https://github.com/alfiankan/crab-config-files-templating/releases/download/v1.0.5/crab-v1.0.5-linux-amd64.tar.gz -O - | tar -xz crab - name: recreate deployment manifest on production run: | ./crab -f example/manifest/nginx.yaml
-r namespace=production
-r publishPort=80
-q portName=prod-server
-o nginx-prod.yaml
-v - name: view manifest run: cat nginx-prod.yaml

Related article

• Replacing kubernetes manifest value dynamicly (coming soon on medium)