Month: April 2018

Kubernetes with Docker for Mac

The newer versions of Docker for Mac actually bring everything for the use of Kubernetes. Since the current documentation is not so optimal, I try it in my own way. Since I plan to further testing tutorials on this topic, this guide will serve as a basis.

Preparation

Kubernetes is currently only supported via Docker Edge. Caution, if you switch from stable to edge all Docker images and containers will be deleted! If you are already using the Edge version, skip the following steps 1 till 3.

Docker for Mac Version Stable

  1. Download Docker for Mac Edge Version… You can exit Docker for Mac while downloading.
  2. After successful download of DMG start the installation (Replace the old version).
  3. Start Docker and follow the instructions.
  4. Activate Kubernetes now via “Enable Kubernetes” checkbox and install the Kubernetes cluster. This can take a while, do not lose your patience!
  5. When the installation is finished you can check it.

Enable Kubernetes

Docker Version Edge with Kubernetes

Note, if you have already used minikube, you should now switch the cluster. You can switch between clusters at any time via GUI or command-line.

# show kubectl version
$ kubectl version
Client Version: version.Info{Major:"1", Minor:"9", GitVersion:"v1.9.6", GitCommit:"9f8ebd171479bec0ada837d7ee641dec2f8c6dd1", GitTreeState:"clean", BuildDate:"2018-03-21T15:21:50Z", GoVersion:"go1.9.3", Compiler:"gc", Platform:"darwin/amd64"}
Unable to connect to the server: dial tcp 192.168.99.100:8443: i/o timeout

# show current context
$ kubectl config current-context
minikube

# switch context
$ kubectl config use-context docker-for-desktop
Switched to context "docker-for-desktop".

# show kubectl version
$ kubectl version
Client Version: version.Info{Major:"1", Minor:"9", GitVersion:"v1.9.6", GitCommit:"9f8ebd171479bec0ada837d7ee641dec2f8c6dd1", GitTreeState:"clean", BuildDate:"2018-03-21T15:21:50Z", GoVersion:"go1.9.3", Compiler:"gc", Platform:"darwin/amd64"}
Server Version: version.Info{Major:"1", Minor:"9", GitVersion:"v1.9.6", GitCommit:"9f8ebd171479bec0ada837d7ee641dec2f8c6dd1", GitTreeState:"clean", BuildDate:"2018-03-21T15:13:31Z", GoVersion:"go1.9.3", Compiler:"gc", Platform:"linux/amd64"}

Now it’s a good time to know some more about current cluster, nodes, pods and namespaces. This will help to understand everything better!

# show cluster informations
$ kubectl cluster-info
Kubernetes master is running at https://localhost:6443
KubeDNS is running at https://localhost:6443/api/v1/namespaces/kube-system/services/kube-dns:dns/proxy

To further debug and diagnose cluster problems, use 'kubectl cluster-info dump'.

# show nodes informations
$ kubectl get nodes
NAME                 STATUS    ROLES     AGE       VERSION
docker-for-desktop   Ready     master    14m       v1.9.6

# show pod informations
$ kubectl get pods
No resources found.

# show namespaces informations
$ kubectl get namespaces
NAME          STATUS    AGE
default       Active    23m
docker        Active    21m
kube-public   Active    23m
kube-system   Active    23m

As you can see, everything is working fine. The system is now ready for usage. By the way, have a look on your Docker images!

# list current Docker images (optional)
$ docker images
...

Deploying the Kubernetes Web UI Dashboard

Finally we deploy the Kubernetes Web UI Dashboard on our new Kubernetes Master as a Pod in namespace kube-system. The Dashboard is not installed/deployed by default. Although everything is possible via command-line, it can help to better understand and analyze the system.

# create a resource from a file
$ kubectl create -f https://raw.githubusercontent.com/kubernetes/dashboard/master/src/deploy/recommended/kubernetes-dashboard.yaml
secret "kubernetes-dashboard-certs" created
serviceaccount "kubernetes-dashboard" created
role "kubernetes-dashboard-minimal" created
rolebinding "kubernetes-dashboard-minimal" created
deployment "kubernetes-dashboard" created
service "kubernetes-dashboard" created

# list pods in specific namespace
$ kubectl get pods --namespace=kube-system
NAME                                         READY     STATUS    RESTARTS   AGE
etcd-docker-for-desktop                      1/1       Running   0          46m
kube-apiserver-docker-for-desktop            1/1       Running   0          46m
kube-controller-manager-docker-for-desktop   1/1       Running   0          46m
kube-dns-6f4fd4bdf-f7pjw                     3/3       Running   0          47m
kube-proxy-c676q                             1/1       Running   0          47m
kube-scheduler-docker-for-desktop            1/1       Running   0          46m
kubernetes-dashboard-5bd6f767c7-f9w4j        1/1       Running   0          1m

# forward port to specific pod (Attention! Your pod may have a different name!)
$ kubectl port-forward kubernetes-dashboard-5bd6f767c7-f9w4j 8443:8443 --namespace=kube-system
Forwarding from 127.0.0.1:8443 -> 8443

# open Web UI Dashboard
$ open https://localhost:8443

Skip Authentication

You can skip authentication and jump directly to the dashboard. This step should may give you a hint. Never ever do the same in production!

Kubernetes Dashboard

That’s it already! Have a look on created dashboard and get familiar with your new Kubernetes environment.

PHP QA Tools and Docker Jenkins

This Tutorial is about some simple PHP QA Tools and Docker Jenkins. I will show near how to install PHP and PHP Composer in an Jenkins Alpine Linux Docker inclusive some needed Jenkins PlugIns.

Note

If you have an running Docker Container already which you cannot stop, you can install needed packages directly via:

# list containers (optional)
$ docker ps -a

# access running container as root
$ docker exec -u 0 -it <Container Name> sh

# install packages and exit container
...

Now you can use the same commented commands as provided via Dockerfile. Otherwise follow next steps.

Let’s go

# create new project
$ mkdir -p ~/Projects/DockerJenkins && cd ~/Projects/DockerJenkins/

# create Dockerfile and plugins.txt
$ touch Dockerfile plugins.xt

# modify Dockerfile
$ vim Dockerfile

# modify plugins.txt
$ vim plugins.txt
FROM jenkins/jenkins:lts-alpine

USER root

RUN apk update && apk upgrade

# install needed libary packages
RUN apk --no-cache add libssh2 libpng freetype libjpeg-turbo libgcc \
libxml2 libstdc++ icu-libs libltdl libmcrypt

# install needed PHP packages
RUN apk --no-cache add php7 php7-fpm php7-opcache php7-gd php7-pdo_mysql \
php7-mysqli php7-mysqlnd php7-mysqli php7-zlib php7-curl php7-phar \
php7-iconv php7-pear php7-xml php7-pdo php7-ctype php7-mbstring \
php7-soap php7-intl php7-bcmath php7-dom php7-xmlreader php7-openssl \
php7-tokenizer php7-simplexml php7-json

# Download and install composer installer
RUN php -r "copy('https://getcomposer.org/installer', 'composer-setup.php');"
RUN php -r "if (hash_file('SHA384', 'composer-setup.php') === '544e09ee996cdf60ece3804abc52599c22b1f40f4323403c44d44fdfdd586475ca9813a858088ffbc1f233e9b180f061') { echo 'Installer verified'; } else { echo 'Installer corrupt'; unlink('composer-setup.php'); } echo PHP_EOL;"
RUN php composer-setup.php
RUN mv composer.phar /usr/local/bin/composer
RUN chmod +x /usr/local/bin/composer
RUN rm -f composer-setup.php

USER jenkins

# install plugins from plugins.txt
COPY plugins.txt /usr/share/jenkins/ref/plugins.txt
RUN /usr/local/bin/install-plugins.sh < /usr/share/jenkins/ref/plugins.txt

checkstyle:3.50
analysis-core:1.95
dry:2.50
pmd:3.50
violations:0.7.11

That was it! Now build the image, start and work with jenkins.

# build image from Dockerfile
$ docker build -t lupin/jenkins:lts-alpine .

# list images (optional)
$ docker images

# start container
$ docker run --name JenkinsPHP -p 8080:8080 lupin/jenkins:lts-alpine

Test

After starting, configuring and logging, you can see the already installed plugins in the Jenkins PlugIns!

Jenkins PlugIns

To test, you can create a simple freestyle job. Here you configure the repository, build steps and post-build actions. After a few runs, the results should be visible on the project side.

Jenkins Build Results