Ship Week 1: Intro to Continuous Delivery and GitOps When building cloud native applications, software developers are no longer just responsible for coding new features. In the next module of Summer of Kubernetes, our expert guides (with the help of some special guests) will cover how to safely and effectively ship software without disrupting end users. To do this you will: ✅ Understand the basics of continuous delivery and GitOps ✅ Learn about how K8s enables declarative CD (via the use of reconciliation loops)

1. Summer of K8s: Ship – Week 1
Continuous Delivery and GitOps 101
Daniel Bryant
@danielbryantuk
www.getambassador.io/summer-of-k8s

2. Join us for the Summer of K8s!
08/07/2021 @danielbryantuk
https://www.getambassador.io/summer-of-k8s/ship/

3. K8s and containers: Expectations vs reality
08/07/2021 @danielbryantuk
“SRE”

4. Continuous Delivery
08/07/2021 @danielbryantuk

5. Velocity (with stability) is key to business success
“Continuous delivery is achieved when stability and
speed can satisfy business demand.
Discontinuous delivery occurs when stability and speed
are insufficient.”
- Steve Smith (@SteveSmithCD)
08/07/2021 @danielbryantuk

6. Velocity (with stability) is key to business success
“Continuous delivery is achieved when stability and
speed can satisfy [your] business demand.
Discontinuous delivery occurs when stability and speed
are insufficient.”
- Steve Smith (@SteveSmithCD)
08/07/2021 @danielbryantuk

7. 08/07/2021 @danielbryantuk
Feedback:
- Was our initial
hypothesis proven?
- How can we improve
business, architecture
and ops?

8. Impact of container tech on CD
08/07/2021 @danielbryantuk

9. 08/07/2021 @danielbryantuk

10. 08/07/2021 @danielbryantuk

11. Diving Deeper into CI, CD, CD, PD
08/07/2021 @danielbryantuk

12. CI, CD, CD, WAT?
• Continuous integration (CI) is a methodology in which developers test and
build (integrate) their code changes as often as possible.
• Continuous delivery (CD) is the capability of releasing code at any time. CD
assumes that your code has passed the CI pipeline and any tests that you
deem necessary (such as smoke testing, QA, and load testing).
• Continuous deployment takes continuous delivery a step further by
automatically releasing the application once it passes the required tests.
cloud.google.com/architecture/addressing-continuous-delivery-challenges-in-a-kubernetes-world
08/07/2021 @danielbryantuk

13. Definitions
• Artifact
• The application unit e.g. JAR, ZIP file, container
• The usual output of a CI pipeline is an artifact in an artifact storage system
• Version
• An annotated instance of an artifact
• Can be semver e.g. major.minor.path (1.4.2)
• Environment
• The infrastructure or set of computing, networking, and storage resources on which
you deploy your application.
08/07/2021 @danielbryantuk

14. Definitions
• Artifact: Container
• The application unit e.g. JAR, ZIP file, container
• The usual output of a CI pipeline is an artifact in an artifact storage system
• Version: Container label (and config)
• An annotated instance of an artifact
• Can be semver e.g. major.minor.path (1.4.2)
• Environment: Cluster and namespace
• The infrastructure or set of computing, networking, and storage resources on which
you deploy your application.
08/07/2021 @danielbryantuk

15. K8s Concepts
• Four main K8s objects to deploy an application on Kubernetes:
• The ReplicaSet object lets you specify the number of Pods of your app
• The Deployment object helps automate ReplicaSets, for example, by gradually
replacing an old ReplicaSet with a new one.
• The StatefulSet…
• The DaemonSet…
• Configuration
• ConfigMap
• Secrets
08/07/2021 @danielbryantuk

16. Useful K8s features
• PodDisruptionBudgets
• Liveness Probes,
• Readiness Probes,
• startupProbe,
• Readiness gates
• Good examples:
• loft.sh/blog/kubernetes-readiness-probes-examples-common-pitfalls/
08/07/2021 @danielbryantuk

17. K8s Concepts
• Don’t forget one-off tasks!
• Jobs
• CronJobs
• Be careful with these
• Don’t make my mistake J
08/07/2021 @danielbryantuk

18. Progressive Delivery
• Very much like continuous delivery
• Some argue it’s the same…
• Clearly separate deploy and release
• Incrementally release features
• Rollout changes to subset of users
• Automated (observability) feedback
• Mechanisms
• Blue/green
• Canary releases
• Dark launch
08/07/2021 @danielbryantuk
redmonk.com/jgovernor/2018/08/06/towards-progressive-delivery/

19. GitOps
08/07/2021 @danielbryantuk

20. What is GitOps?
• “GitOps is a paradigm or a set of practices that empowers developers
to perform tasks which typically fall under the purview of IT
operations. ”
• “GitOps is an operational framework that takes DevOps best practices
used for application development such as version control,
collaboration, compliance, and CI/CD tooling, and applies them to
infrastructure automation.”
• “It’s a new way to sell CD software/frameworks” (just kidding)
08/07/2021 @danielbryantuk

21. GitOps
• “A git repo is the single source of truth for the desired state of the
whole system.
• All changes to the desired state are Git commits.
• All specified properties of the cluster are also observable in the
cluster, so that we can detect if the desired and observed states are
the same (converged) or different (diverged). "
08/07/2021 @danielbryantuk
www.weave.works/blog/what-is-gitops-really

22. GitOps
7/8/21 @danielbryantuk
www.weave.works/blog/what-is-gitops-really

23. Wrapping Up
08/07/2021 @danielbryantuk

24. A peak to our future: Argo Hands-On!
08/07/2021 @danielbryantuk

25. Join us for the Summer of K8s!
08/07/2021 @danielbryantuk
https://www.getambassador.io/summer-of-k8s/ship/