docs: fix error example in deployment strategies

[mumubin]

in my test, the example canary doesn't work. After removing promotion, it works.

[stefanprodan]

These are snippets about promotion step weight, the promotion field is optional while the canary step weight is mandatory.

[mumubin]

mandatory

Sorry, I didn't get you. The example in doc throw a grammatical error.
Could you give a detail example or help me figure out what's wrong with my test?

Env:
flagger version 1.32.0

My test canary:

apiVersion: flagger.app/v1beta1
kind: Canary
metadata:
  name: podinfo
  namespace: flagger-bin
spec:
  provider: nginx
  # deployment reference
  targetRef:
    apiVersion: apps/v1
    kind: Deployment
    name: podinfo
  # ingress reference
  ingressRef:
    apiVersion: networking.k8s.io/v1
    kind: Ingress
    name: podinfo
  # the maximum time in seconds for the canary deployment
  # to make progress before it is rollback (default 600s)
  progressDeadlineSeconds: 6000
  service:
    # ClusterIP port number
    port: 80
    # container port number or name
    targetPort: 9898
  analysis:
    # schedule interval (default 60s)
    interval: 60s
    # max number of failed metric checks before rollback
    threshold: 10
    # max traffic percentage routed to canary
    # percentage (0-100)
    # canary increment step
    # percentage (0-100)
    # stepWeight: 5
    # NGINX Prometheus checks
    #stepWeights: [1, 2, 10, 80]
    promotion:
      maxWeight: 50
      stepWeight: 20

Applied with error:

> kubectl apply -f podinfo-canary.yml -n flagger-bin
error: error validating "podinfo-canary.yml": error validating data: ValidationError(Canary.spec.analysis): unknown field "promotion" in app.flagger.v1beta1.Canary.spec.analysis; if you choose to ignore these errors, turn validation off with --validate=false

After changing to the following canary.yaml. it works.

apiVersion: flagger.app/v1beta1
kind: Canary
metadata:
  name: podinfo
  namespace: flagger-bin
spec:
  provider: nginx
  # deployment reference
  targetRef:
    apiVersion: apps/v1
    kind: Deployment
    name: podinfo
  # ingress reference
  ingressRef:
    apiVersion: networking.k8s.io/v1
    kind: Ingress
    name: podinfo
  # the maximum time in seconds for the canary deployment
  # to make progress before it is rollback (default 600s)
  progressDeadlineSeconds: 6000
  service:
    # ClusterIP port number
    port: 80
    # container port number or name
    targetPort: 9898
  analysis:
    # schedule interval (default 60s)
    interval: 60s
    # max number of failed metric checks before rollback
    threshold: 10
    # max traffic percentage routed to canary
    # percentage (0-100)
    # maxWeight: 50
    # canary increment step
    # percentage (0-100)
    # stepWeight: 5
    # NGINX Prometheus checks
    #stepWeights: [1, 2, 10, 80]
    maxWeight: 50
    stepWeight: 20

[stefanprodan]

LGTM

Thanks @mumubin