build docker image with kaniko and jenkins running on kubernetes

Prerequisite

• a running kubernetes cluster , you can use minikube as well；
• a running and configured jenkins in kubernetes
• username and password for accessing source code repository, if you are using github , just pass token instead.
• credentials like database connection strings you wanna pass to during building image
• docker-registry secret infomation in order to push image to your registry

What is kaniko & Why kaniko?

we can not easily access to docker deamon since Docker runtime support is removed in a future release(currently planned for the 1.22 release in late 2021) of Kubernetes, here is kaniko come to save the day.kaniko is a tool to build container images from a Dockerfile, inside a container or Kubernetes cluster.

Quick Start

1 apply following command which contains docker-registry auth info to cluster

kubectl --namespace default \
create secret \
docker-registry regcred \
--docker-server https://your.registry.url \
--docker-username your_user_name \
--docker-password your_password \
--docker-email your_email_address

2 Store your credentials to jenkins secret text those credentials will be used in Jenkinsfile like below

environment {            
   SERVICE_NAME = "shop-api"           
   REGISTRY = "registry.cn-hangzhou.aliyuncs.com/hyper/${SERVICE_NAME}" 
   // credencials database connectionstring 
    StoreConnection = credentials('StoreConnection') 
    IdentityConnection = credentials('IdentityConnection') 
    GitHub = credentials('GitHub')
                       }

3 Set up a jenkins pipeline ,specify build with Jenkinsfile, then pull current repository