Creating a fast Kubernetes Development Workflow

Kubernetes is very powerful in orchestrating where your services are running, but building docker images, writing and updating all the necessary YAML files and applying them to your cluster can still become an annoying maintenance overhead.
In this talk you will learn how to create a fast, low friction development workflow with Kubernetes and tools like Telepresence and Forge which enables you to quickly and safely build, test and deploy your services.

Transcript

1. @BastianHofmann
   Creating a fast
   Kubernetes Development Workflow
   Bastian Hofmann
   

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3. Container orchestration platform
   

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4. Deploy, run and scale your services
   in isolated containers
   

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5. Very Powerful
   

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6. Large community
   

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7. Lot’s of large company backers
   

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8. No vendor lock in
   

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9. Runs on
   

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10. Your laptop
    

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11. Included in Docker Desktop Clients
    

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12. Bare metal
    

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13. Cloud Providers
    

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14. AWS
    

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15. Azure
    

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16. Google Cloud Platform
    

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17. And if you don't want to install and
    maintain Kubernetes yourself
    

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18. Managed Kubernetes
    

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19. Google GKE
    

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20. Amazon EKS
    

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21. SysEleven MetaKube
    

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22. Easy upgrades
    

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23. Easy scaling
    

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24. Load Balancing
    

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25. Distributed Persistent Storage
    

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26. Backups
    

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27. Premium support
    

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28. We monitor you cluster, ensure it's
    working and tell you if something is
    wrong
    

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29. German company
    with German datacenters
    

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30. You can focus on what is important
    

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31. But this talk is about
    how to use Kubernetes
    

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32. Not only for production workloads
    

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33. But in your development workflows
    

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34. Kubernetes has standardized apis
    

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35. More and more integrations
    

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36. Great tools
    

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37. Agenda
    

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38. Introduction to Kubernetes
    

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39. Deployment of a simple application
    

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40. Deployment of a micro-service
    application
    

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41. Some tools for development with
    Kubernetes
    

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42. But first
    

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43. Why containers?
    

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44. Services run in isolation
    

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45. Everything needed to run a service in
    one image
    

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46. Decouple
    Ops and Dev
    

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47. Make things …
    

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48. Easier to deploy
    

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49. Easier to upgrade system
    dependencies
    

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50. Easier to scale
    

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51. Easier to develop
    

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52. Kubernetes helps you deploying
    containers
    

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53. Kubernetes helps you running
    containers
    

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54. Kubernetes helps you scaling
    containers
    

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55. Let’s define some core concepts and
    terminology first
    

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56. Kubernetes Cluster
    

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57. • A docker image built from
    a Dockerfile that contains
    everything a service needs
    to run
    Image
    

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58. • A container runs a docker
    image.
    • Only 1 process can run
    inside of a container
    Container
    

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59. • A group of 1 or more
    containers
    • Same port space
    • Ports are not accessible
    from outside of the pod
    Pod
    

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60. • Defines and manages how
    many instances of a pod
    should run
    Replica Set
    

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61. • Manages updates and
    rollbacks of replica sets
    Deployment
    

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62. • Makes a port of a pod
    accessible to other pods
    Service
    

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63. • Makes a service
    accessible to the outside
    of Kubernetes
    Ingress
    

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64. Volumes, ConfigMaps, Secrets,
    PersistentVolumeClaims, CronJobs,
    StatefulSets, ...
    

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65. Everything is a resource
    

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66. You interact with Kubernetes by
    creating, receiving, updating and
    deleting resources
    

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67. Kubernetes has controllers to listen
    on these interactions and get the
    cluster in the desired state
    

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68. kind: Deployment
    apiVersion: extensions/v1beta1
    metadata:
    name: symfony-demo
    spec:
    template:
    spec:
    containers:
    - name: symfony-demo
    image: symfony-demo:1.1.0
    ports:
    - containerPort: 80
    

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69. $ kubectl create -f deployment.yaml
    

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70. $ kubectl get deployments
    NAME DESIRED CURRENT UP-TO-DATE AVAILABLE
    AGE
    symfony-demo 1 1 1 1
    21h
    

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71. $ kubectl get deployment symfony-demo -o yaml
    apiVersion: extensions/v1beta1
    kind: Deployment
    metadata:
    annotations:
    ...
    spec:
    ...
    template:
    ...
    spec:
    containers:
    - name: symfony-demo
    image: symfony-demo:1.1.0
    

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72. $ kubectl delete deployment symfony-demo
    

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73. Practical example
    

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74. Preparations
    

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75. We need a cluster
    

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79. Let’s deploy the symfony demo app
    

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80. https:/
    /github.com/symfony/demo
    

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81. Demo
    

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82. Dockerfile
    

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83. Copy our code
    

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84. Build the project
    

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85. Composer install
    

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86. yarn install
    

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87. yarn run build
    

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88. https:/
    /docs.docker.com/develop/develop-
    images/multistage-build/
    

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89. Build the image
    

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90. docker build -t symfony-demo:2.0.0 .
    

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91. Now we have to tell Kubernetes
    what to do with the image
    

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92. Resources are defined in YAML or
    JSON
    

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93. Deployment
    

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94. kind: Deployment
    apiVersion: extensions/v1beta1
    metadata:
    name: symfony-demo
    spec:
    template:
    metadata:
    labels:
    app: symfony-demo
    spec:
    containers:
    - name: symfony-demo
    image: symfony-demo:1.0.0
    ports:
    

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95. containers:
    - name: symfony-demo
    image: symfony-demo:1.0.0
    ports:
    - containerPort: 80
    livenessProbe:
    httpGet:
    path: /
    port: 80
    timeoutSeconds: 1
    initialDelaySeconds: 10
    readinessProbe:
    httpGet:
    path: /
    

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96. Many more options configurable
    

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97. Many more options
    • Setting environment variables
    • Mounting volumes
    • Requesting resources
    • Defining upgrade strategies
    • Defining command
    • Configure networking
    • Configure the scheduler
    • Listen on lifecycle events
    • Configure system capabilities for the container
    • …
    

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98. Service
    

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99. kind: Service
    apiVersion: v1
    metadata:
    name: symfony-demo
    spec:
    ports:
    -
    name: http
    port: 80
    targetPort: 80
    protocol: TCP
    selector:
    app: symfony-demo
    

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100. Ingress
     

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101. kind: Ingress
     apiVersion: extensions/v1beta1
     metadata:
     name: symfony-demo
     spec:
     rules:
     - host: symfony-demo.local.k8s
     http:
     paths:
     - path: /
     backend:
     serviceName: symfony-demo
     servicePort: 80
     

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102. Creating everything
     

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103. kubectl apply -f deployment/webapp.yaml
     

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105. Rolling Deployments
     

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106. kind: Deployment
     apiVersion: extensions/v1beta1
     metadata:
     name: symfony-demo
     spec:
     template:
     spec:
     containers:
     - name: symfony-demo
     image: symfony-demo:1.1.0
     ports:
     - containerPort: 80
     

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107. kubectl apply -f deployment/webapp.yaml
     

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108. Writing this YAML files is tedious
     

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109. YAML files are tied to a specific
     version and a specific environment
     

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110. Production
     

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111. Staging
     

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112. Development
     

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113. Per Development team
     

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114. Per branch
     

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115. Per developer
     

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116. Built-in
     

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117. Namespaces
     

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118. Still we'd need to maintain multiple
     very similar YAML files with slightly
     different versions and configuration.
     

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119. "Templating"
     

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120. Great tools because of standardized
     Kubernetes API
     

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121. Helm
     

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123. Allows to install applications
     

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124. So called "charts"
     

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125. Writing your own charts if fairly easy
     

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126. Charts can depend on other charts
     

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127. Multiple deployments of one chart
     possible
     

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128. Different namespaces
     

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129. Different release names
     

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130. Configuration over values
     

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132. Different versions
     

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133. Different ingress urls
     

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134. $ helm install stable/wordpress --namespace bastian --name
     my-wordpress --values dev.yaml --values bastian.yaml
     

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135. Still:
     

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136. Make a code change
     

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137. Build docker image
     

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138. Push docker image
     

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139. Run helm install/upgrade with new
     image version
     

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140. Can this be quicker?
     

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141. Forge
     

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143. Similar templating to helm
     

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144. Services can depend on other
     services
     

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145. $ forge deploy
     

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146. Supports different profiles
     

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147. $ forge --profile staging deploy
     

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148. $ forge --profile bastian deploy
     

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149. Different profiles can deploy to
     different namespaces with different
     ingress hostnames
     

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150. Default profile can be dependent on
     the branch you are building from
     

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151. You can use the branch name in
     templates
     

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152. Demo application
     

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153. web
     quote-svc
     hello-svc
     

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154. Not all services have an ingress
     

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155. Accessing Kubernetes from the
     outside
     

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156. web
     quote-svc
     hello-svc
     

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157. Getting a shell in a running container
     

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158. $ kubectl exec $POD_NAME -i -t -- /bin/bash
     

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159. Port forwarding through kubectl
     

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160. $ kubectl port-forward pod/$POD_NAME 8080:80
     

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161. $ kubectl port-forward service/$SERVICE_NAME 8080:80
     

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162. Still, if you make a code change you
     have to commit, push, build, deploy
     

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163. Takes some time
     

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164. What about step debugging?
     

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165. Of course you can run everything
     locally
     

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166. But you develop only on one service
     

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167. There may be lots of services
     

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168. Telepresence
     

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170. Creates a two-way proxy between
     the Kubernetes cluster and you
     

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171. $ telepresence
     T: Starting proxy with method 'vpn-tcp'...
     @fhgbvx65xg|bash-3.2$ curl http://quote-svc/quote | jq '.'
     [
     {
     "ID": 503,
     "title": "stefan sagmeister",
     "content": "...\n",
     "link": "https://quotesondesign.com/stefan-
     sagmeister-2/"
     }
     ]
     

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172. Swap a running deployment in the
     cluster with a local process
     

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173. ... or a locally running docker
     container
     

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174. $ telepresence --swap-deployment quote-svc --namespace
     dev-flow-demo --expose 3000 --run npm run debug
     T: Starting proxy with method 'vpn-tcp',...
     T: Forwarding remote port 3000 to local port 3000....
     > quote-svc@1.0.0 debug /Users/bhofmann/forge_test/quote-
     svc
     > nodemon --inspect quote-svc.js
     [nodemon] watching: *.*
     [nodemon] starting `node --inspect quote-svc.js`
     Debugger listening on ws://127.0.0.1:9229/83aa27ac-
     d879-4b50-a228-440354cca791
     quote svc listening on port 3000!
     

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175. Demo
     

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176. Summary
     

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177. Powerful
     

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178. Helpful
     

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179. Great tooling because of common
     APIs
     

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180. Especially great if you have multiple
     services and don't want to run
     everything locally
     

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181. http:/
     /speakerdeck.com/
     u/bastianhofmann
     

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182. mail@bastianhofmann.de
     https:/
     /twitter.com/BastianHofmann
     

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