Tekton主要组件调用关系

Refer to: Udemy

  

示例调用结构图

 

示例调用关系 

1. Webhook & REST 请求 
外部通过 REST 方式发送包含  {"firstname":"John", "lastname":"Doe"}  的事件 payload，触发整个流程。 
​ 
2. EventListener（5-09-el） 
它监听上述带有事件 payload 的 curl 请求，然后关联到 5-09-trigger。 
​ 
3. Trigger（5-09-trigger） 
包含三个关键组件： 
​ 
- TriggerTemplate（5-09-tt）：用于实例化 5-09-pipeline。 
​ 
- TriggerBinding（5-09-tb）：负责结构化处理 payload 中的  firstname  和  lastname 。 
​ 
- Interceptor（cel-interceptor）：仅当 payload 被接受时，才允许事件传递。 
​ 
4. Pipeline（5-09-pipeline） 
它关联到 5-09-task，是 Pipeline 的实例化（PipelineRun）。 
​ 
5. Task（5-09-task） 
最终执行打印名字的操作，输出  firstname  和  lastname 。 

总结调用链： 
 REST 请求（带 payload）  →  EventListener（5-09-el）  →  Trigger（5-09-trigger）  →  Pipeline（5-09-pipeline）  →  Task（5-09-task）  →  打印姓名   



在上面第三步 Trigger（5-09-trigger）中，三个组件的调用关系如下： 

1. Interceptor（cel-interceptor）：首先对事件 payload 进行校验，只有当 payload 符合要求时，才允许事件继续传递。 
​ 
2. TriggerBinding（5-09-tb）：在 Interceptor 校验通过后，对 payload 中的  firstname  和  lastname  进行结构化处理，提取出可用的参数。 
​ 
3. TriggerTemplate（5-09-tt）：使用 TriggerBinding 处理后的参数，来实例化 5-09-pipeline，从而触发后续的 Pipeline 流程。 

简单来说，调用顺序是： Interceptor 校验  →  TriggerBinding 结构化参数  →  TriggerTemplate 实例化 Pipeline 。

 

示例代码

kubectl run curl-pod --image=curlimages/curl:latest --command -- sleep infinity
kubectl exec -it curl-pod -- /bin/sh

curl -X POST http://el-5-09-el.default.svc.cluster.local:8080 \
    -H 'Content-Type: application/json' \
    -d '{"firstname":"John", "lastname":"Doe"}'

curl -X POST http://el-5-09-el.default.svc.cluster.local:8080 \
    -H 'Content-Type: application/json' \
    -d '{"firstname":"John", "surname":"Doe"}'
kubectl logs -l eventlistener=5-09-el #-n tekton-pipelines

apiVersion: triggers.tekton.dev/v1beta1
kind: EventListener
metadata:
  name: 5-09-el
  namespace: default
spec:
  triggers:
    - triggerRef: 5-09-trigger
  serviceAccountName: tekton-triggers-example-sa

apiVersion: triggers.tekton.dev/v1beta1
kind: Trigger
metadata:
  name: 5-09-trigger
  namespace: default
spec:
  bindings:
    - ref: 5-09-tb
  template:
    ref: 5-09-tt
  interceptors:
    - ref:
        name: cel
      params:
        - name: filter
          value: "has(body.firstname) && has(body.lastname)"

apiVersion: triggers.tekton.dev/v1beta1
kind: TriggerBinding
metadata:
  name: 5-09-tb
  namespace: default
spec:
  params:
    - name: firstname
      value: $(body.firstname)
    - name: lastname
      value: $(body.lastname)

apiVersion: triggers.tekton.dev/v1beta1
kind: TriggerTemplate
metadata:
  name: 5-09-tt
  namespace: default
spec:
  params:
    - name: firstname
    - name: lastname
  resourcetemplates:
    - apiVersion: tekton.dev/v1beta1
      kind: PipelineRun
      metadata:
        generateName: simple-pipeline-run-
        namespace: default
      spec:
        pipelineRef:
          name: 5-09-pipeline
        params:
          - name: firstname
            value: $(tt.params.firstname)
          - name: lastname
            value: $(tt.params.lastname)

apiVersion: tekton.dev/v1beta1
kind: Pipeline
metadata:
  name: 5-09-pipeline
  namespace: default
spec:
  params:
    - name: firstname
      type: string
    - name: lastname
      type: string
  tasks:
    - name: print-fields-task
      taskRef:
        name: 5-09-task
      params:
        - name: firstname
          value: $(params.firstname)
        - name: lastname
          value: $(params.lastname)

apiVersion: tekton.dev/v1beta1
kind: Task
metadata:
  name: 5-09-task
  namespace: default
spec:
  params:
    - name: firstname
      type: string
    - name: lastname
      type: string
  steps:
    - name: echo-fields
      image: ubuntu
      script: |
        #!/bin/bash
        echo "$(params.firstname) $(params.lastname)"

 

 

rbac.yaml

apiVersion: v1
kind: ServiceAccount
metadata:
  name: tekton-triggers-example-sa
  namespace: default
---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
  name: triggers-example-eventlistener-binding
  namespace: default
subjects:
  - kind: ServiceAccount
    name: tekton-triggers-example-sa
    namespace: default
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: tekton-triggers-eventlistener-roles
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: triggers-example-eventlistener-clusterbinding
subjects:
  - kind: ServiceAccount
    name: tekton-triggers-example-sa
    namespace: default
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: tekton-triggers-eventlistener-clusterroles