Export command doesn't honour --mode flag

[dsimansk]

Bug report

When --mode flag is specified for ksvc without --with-revisions flag that output format is plain Knative Service yaml instead of our custom Export type.

➜  ~ kn service export hello -o yaml --mode export                 
apiVersion: serving.knative.dev/v1
kind: Service
metadata:
  creationTimestamp: null
  name: hello
spec:
  template:
    metadata:
      annotations:
        client.knative.dev/user-image: docker.io/dsimansk/helloworld
      creationTimestamp: null
      name: hello-djrrc-1
    spec:
      containerConcurrency: 0
      containers:
      - env:
        - name: TARGET
          value: v1
        image: docker.io/dsimansk/helloworld
        name: user-container
        readinessProbe:
          successThreshold: 1
          tcpSocket:
            port: 0
        resources: {}
      enableServiceLinks: false
      timeoutSeconds: 300
status: {}

Expected behavior

kn service export hello -o yaml --mode export - output is printed in requested Export format.

Steps to reproduce the problem

Exec and check the format.

 kn service export hello -o yaml --mode export                 

kn version

HEAD

Knative (serving/eventing) version

Nightly

/kind good-first-issue

[dsimansk]

@itsmurugappan please let know if you'd like to work on this one or should I.

[itsmurugappan]

Sure I can work on it. /assign

[itsmurugappan]

/assign

[github-actions]

This issue is stale because it has been open for 90 days with no
activity. It will automatically close after 30 more days of
inactivity. Reopen the issue with /reopen. Mark the issue as
fresh by adding the comment /remove-lifecycle stale.

[dsimansk]

/remove-lifecycle stale

[rhuss]

@dsimansk The fix should be available now in #1212 Would you mind to give the PR a review please and eventually close this issue if the PR fixes it ?

[dsimansk]

Per WG call discussion I'd like to start a vote on the --mode flag default value since the PR to fix mode flag also sets default.

Option A:
The --mode flag default is replay. The Service and Revisions are exported as plain Kubernetes custom resource, either single Service or list of resources with multiple Revisions. The format is meant to be used with kubectl to recreate/import.

Option B:
The --mode flag default is export. The format is meant to be used with kn service import. It's our spin-off resource format that should give us better control when kn is used to import/recreate resources. The kn's import command only accepts its own Export format.

Given the fact export and import commands are tied together I personally think that we should promote --mode=export as default. To have our commands work together without additional parameters. The user might not know that to get import with kn, there's need to specify it's export format etc. One could expect that kn service export is producing the correct result to be used with kn service import.

Please vote on the comments bellow.