Understanding Tekton: A Comprehensive Guide to Cloud-Native CI/CD
Published: 2024-01-03 11:25:31


![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/hl561ywwquu1226ma0dh.png)
**Introduction:**
_Tekton is an open-source project that facilitates the creation and operation of cloud-native continuous integration and continuous delivery (CI/CD) pipelines. In this blog post, we'll explore the fundamentals of Tekton, its architecture, and its role in the modern DevOps landscape._

**What is Tekton?**
_Tekton is a Kubernetes-native CI/CD framework that provides a set of custom resources and controllers to define and run CI/CD pipelines as containers in Kubernetes clusters. It is designed to be flexible, extensible, and scalable, making it an excellent choice for building cloud-native applications._

**Key Components of Tekton:**
**Task:**
_A Task is the smallest unit of work in Tekton. It represents a single, well-defined step in the CI/CD pipeline. Tasks can be reused across different pipelines._

**Pipeline:**
_A Pipeline defines a series of interconnected tasks to be executed as part of the CI/CD process. Pipelines enable the orchestration of tasks and define the workflow._

**PipelineRun:**
_A PipelineRun is an instantiation of a Pipeline. It represents a single execution of a CI/CD process, tying together the defined tasks and pipelines._

**Trigger:**
_Tekton Triggers allow the automation of pipeline execution based on events. Events can be external (e.g., a new code push) or internal (e.g., a time-based trigger)._

**Tekton Architecture:**
_Tekton is built on a set of custom Kubernetes resources, allowing it to seamlessly integrate with Kubernetes-native features. The architecture includes:_

**Controller:**
_The Tekton Controller manages the custom resources and orchestrates the execution of tasks and pipelines. It monitors changes in resources and ensures the desired state is maintained._

**CRDs (Custom Resource Definitions):**
_Tekton introduces custom resources such as Task, Pipeline, and Trigger to represent CI/CD concepts. These CRDs define the structure of CI/CD pipelines._

**Tekton CLI:**
_The Tekton CLI (tkn) provides a command-line interface to interact with and manage Tekton resources. It simplifies pipeline management and execution._

**Advantages of Tekton:**
**Portability:**
_Tekton allows you to define CI/CD pipelines as code, making them portable across different Kubernetes clusters. This ensures consistent pipeline execution in various environments._

**Extensibility:**
_Tekton is highly extensible, allowing users to create custom tasks and share them across projects. The extensibility ensures that Tekton can adapt to diverse CI/CD requirements._

**Kubernetes Integration:**
_Tekton leverages native Kubernetes constructs, enabling seamless integration with other Kubernetes tools and services. This integration simplifies the management of CI/CD pipelines within Kubernetes environments._

**Reusability:**
_The modular nature of Tekton allows for the reuse of tasks and pipelines. This promotes code sharing, reduces duplication, and enhances maintainability._

**Getting Started with Tekton:**
**Installation:**
_Install Tekton in your Kubernetes cluster using the provided installation manifests or Helm charts. Tekton can run on any Kubernetes distribution._

**Defining Tasks and Pipelines:**
_Use the Tekton CLI or YAML manifests to define tasks and pipelines. Tasks can be simple, like running tests, or complex, involving multiple steps._

**Executing Pipelines:**
_Trigger the execution of pipelines manually or automate them using Tekton Triggers. Monitor the execution using the Tekton CLI or the Kubernetes dashboard._

**Extending Tekton:**
_Explore and contribute to the Tekton ecosystem by creating custom tasks or integrating existing tools into your pipelines._

**Install Tekton Pipelines**

**Prerequisites**
_A Kubernetes cluster running version 1.25 or later.
Kubectl._
_Grant cluster-admin privileges to the current user._ 
_(Optional) Install a Metrics Server if you need support for high availability use cases._

**Latest official release:**

```
root@master:~# kubectl apply --filename https://storage.googleapis.com/tekton-releases/pipeline/latest/release.yaml

root@master:~# kubectl get pods --namespace tekton-pipelines
NAME                                           READY   STATUS    RESTARTS   AGE
tekton-events-controller-8b5bb559c-fnnvs       1/1     Running   0          6m1s
tekton-pipelines-controller-65fb8b9d46-qbmnm   1/1     Running   0          6m2s
tekton-pipelines-webhook-66ff4b6644-pvhbc      1/1     Running   0          5m54s

```
**Install and set up Tekton Triggers**
**Prerequisites**
_Kubernetes cluster version 1.18 or later._
_Kubectl._
_Tekton Pipelines._
_Grant cluster-admin privileges to the user that installed Tekton Pipelines._ 


![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/rk0emb8smmb9lzz8e2wh.png)
**Configuring a Task**
Define a Task for Building the Node.js Application:

```
#cat build-task.yaml
apiVersion: tekton.dev/v1beta1
kind: Task
metadata:
  name: build-task
spec:
  steps:
    - name: npm-install
      image: node:14
      workingDir: /workspace/source
      script: |
        npm install

    - name: build-app
      image: node:14
      workingDir: /workspace/source
      script: |
        npm run build
```
**This Task consists of two steps:**

**npm-install**: _Installs the Node.js dependencies._
**build-app**: _Builds the Node.js application_

**Define a Task for Deploying the Containerized Application:**

```
#cat deploy-task.yaml
apiVersion: tekton.dev/v1beta1
kind: Task
metadata:
  name: deploy-task
spec:
  steps:
    - name: deploy-app
      image: gcr.io/cloud-builders/kubectl
      script: |
        kubectl apply -f /workspace/source/deployment.yaml

# kubectl get task
NAME                AGE
build-task          16m
deploy-task         16m
```
_This Task includes a single step (deploy-app) that uses the kubectl tool to apply the Kubernetes deployment manifest for your application._

**Define a Pipeline that Uses the Tasks:**

```
#cat example-pipeline.yaml
apiVersion: tekton.dev/v1beta1
kind: Pipeline
metadata:
  name: example-pipeline
spec:
  tasks:
    - name: build
      taskRef:
        name: build-task
    - name: deploy
      taskRef:
        name: deploy-task

# kubectl get pipeline | grep -i example
example-pipeline   15m

```
_This Pipeline consists of two tasks: build and deploy. Each task references the previously defined tasks (build-task and deploy-task)._

**Apply the Tekton Resources:**
_Apply the Tekton resources to your Kubernetes cluster:_

```
kubectl apply -f build-task.yaml
kubectl apply -f deploy-task.yaml
kubectl apply -f example-pipeline.yaml
```
**Run the Pipeline:**

```
# cat pipeline-run.yaml
apiVersion: tekton.dev/v1beta1
kind: PipelineRun
metadata:
  name: example-pipeline-run
spec:
  pipelineRef:
    name: example-pipeline
```

_Apply the PipelineRun to start the execution of the pipeline_

```
kubectl apply -f pipeline-run.yaml
```
**Monitor PipelineRun Status**

```
# kubectl get PipelineRun --watch
NAME                   SUCCEEDED   REASON    STARTTIME   COMPLETIONTIME
example-pipeline-run   Unknown     Running   40s

```