Istio namespace overlay

[kkasravi]

• Define a kustomize manifest to install ISTIO on GCP gcp/{istio,istio-crds,istio-install}
• Rearrange some kustomize manifests as a work around for the fact that kustomize does not preserve install order (i.e. kustomize re-orders config causing fail when crd or admission webhook used kubernetes-sigs/kustomize#821) ?
• Change some kustomize manifests to properly set the namespace due to ingress and istio needing to be installed in the ISTIO namespace
• Add virtual service resources to a bunch of the kustomize packages for webapps.
• remove useIstio: false componentParams

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This change is 

[jlewi]

@hougangliu Can you review this so I'm not the blocker?

@kkasravi how come this PR is modifying 120 files?

[kkasravi]

@jlewi this has been in the queue for a while. Most changes are minor - moving virtual-service.yaml to overlays/istio for example. @gabrielwen is the best choice to review given his familiarity with what the kustomize targets should look like

[jlewi]

Is the PR description accurate?

if useIstio == true, adds bootstrap/config/overlays/istio which will
add components {istio,istio-install} to app.yaml
add istio as an overlay in componentParams for all components which have a virtual-service.yaml

Is that referring to your other PR to modify kfctl?

It looks to me like the changes in this PR are

• Define a kustomize manifest to install ISTIO on GCP
• Rearrange some kustomize manifests as a work around for the fact that kustomize does not preserve install order (i.e. kustomize re-orders config causing fail when crd or admission webhook used kubernetes-sigs/kustomize#821) ?
• Change some kustomize manifests to properly set the namespace due to ingress and istio needing to be installed in the ISTIO namespace
• Add vitual service resources to a bunch of the kustomize packages for webapps.

[jlewi]

Actually is this PR in sync with master?

It looks like most kustomize packages already have virtual-service.yaml file defined inside base. It looks like this PR is defining a virtual service inside the ISTIO overlay.

But the diff doesn't show deleting any deletion of files in base?

What were your reasons for defining virtual service inside ISTIO overlays? I think that makes sense because with the goal of making each application like TFJob/pipelines installed standalone. In standalone mode we don't have a reverse proxy and may not need ISTIO so no need to add virtual services for it.

[jlewi]

Looks like you are pushing commits to this PR. Let me know when its ready for another look.

[jlewi]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: jlewi

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[jlewi]

/hold