Automatic merge from submit-queue
Add initializer support to admission and uninitialized filtering to rest storage
Initializers are the opposite of finalizers - they allow API clients to react to object creation and populate fields prior to other clients seeing them.
High level description:
1. Add `metadata.initializers` field to all objects
2. By default, filter objects with > 0 initializers from LIST and WATCH to preserve legacy client behavior (known as partially-initialized objects)
3. Add an admission controller that populates .initializer values per type, and denies mutation of initializers except by certain privilege levels (you must have the `initialize` verb on a resource)
4. Allow partially-initialized objects to be viewed via LIST and WATCH for initializer types
5. When creating objects, the object is "held" by the server until the initializers list is empty
6. Allow some creators to bypass initialization (set initializers to `[]`), or to have the result returned immediately when the object is created.
The code here should be backwards compatible for all clients because they do not see partially initialized objects unless they GET the resource directly. The watch cache makes checking for partially initialized objects cheap. Some reflectors may need to change to ask for partially-initialized objects.
```release-note
Kubernetes resources, when the `Initializers` admission controller is enabled, can be initialized (defaulting or other additive functions) by other agents in the system prior to those resources being visible to other clients. An initialized resource is not visible to clients unless they request (for get, list, or watch) to see uninitialized resources with the `?includeUninitialized=true` query parameter. Once the initializers have completed the resource is then visible. Clients must have the the ability to perform the `initialize` action on a resource in order to modify it prior to initialization being completed.
```
Add support for creating resources that are not immediately visible to
naive clients, but must first be initialized by one or more privileged
cluster agents. These controllers can mark the object as initialized,
allowing others to see them.
Permission to override initialization defaults or modify an initializing
object is limited per resource to a virtual subresource "RESOURCE/initialize"
via RBAC.
Initialization is currently alpha.
As part of https://github.com/kubernetes/community/pull/132, thsi commit
adds a generic webhook admission controller. This plugin allows for a
completely declarative approach for filtering/matching admission requests
and for matching admission requests, calls out to an external webhook for
handling admission requests.
lifecycle plugin: make use of the libraries under k8s.io/client-go/pkg/api and k8s.io/client-go/kubernetes
for the client libraries instead of k8s.io/kubernetes/client/*
move registration to AdmissionOptions
export functions from pkg/api/validation
add settings API
add settings to pkg/registry
add settings api to pkg/master/master.go
add admission control plugin for pod preset
add new admission control plugin to kube-apiserver
add settings to import_known_versions.go
add settings to codegen
add validation tests
add settings to client generation
add protobufs generation for settings api
update linted packages
add settings to testapi
add settings install to clientset
add start of e2e
add pod preset plugin to config-test.sh
Signed-off-by: Jess Frazelle <acidburn@google.com>
Automatic merge from submit-queue
Add admission controller for default storage class.
The admission controller adds a default class to PVCs that do not require any
specific class. This way, users (=PVC authors) do not need to care about
storage classes, administrator can configure a default one and all these PVCs
that do not care about class will get the default one.
The marker of default class is annotation "volume.beta.kubernetes.io/storage-class", which must be set to "true" to work. All other values (or missing annotation) makes the class non-default.
Based on @thockin's code, added tests and made it not to reject a PVC when no class is marked as default.
.
@kubernetes/sig-storage
The admission controller adds a default class to PVCs that do not require any
specific class. This way, users (=PVC authors) do not need to care about
storage classes, administrator can configure a default one and all these PVCs
that do not care about class will get the default one.
For AWS EBS, a volume can only be attached to a node in the same AZ.
The scheduler must therefore detect if a volume is being attached to a
pod, and ensure that the pod is scheduled on a node in the same AZ as
the volume.
So that the scheduler need not query the cloud provider every time, and
to support decoupled operation (e.g. bare metal) we tag the volume with
our placement labels. This is done automatically by means of an
admission controller on AWS when a PersistentVolume is created backed by
an EBS volume.
Support for tagging GCE PVs will follow.
Pods that specify a volume directly (i.e. without using a
PersistentVolumeClaim) will not currently be scheduled correctly (i.e.
they will be scheduled without zone-awareness).
p0lyn0mial