message PodExecOptions {
  // Redirect the standard input stream of the pod for this call.
  // Defaults to false.
  // +optional
  optional bool stdin = 1;

  // Redirect the standard output stream of the pod for this call.
  // +optional
  optional bool stdout = 2;

  // Redirect the standard error stream of the pod for this call.
  // +optional
  optional bool stderr = 3;

  </mime-type>

  <mime-type type="application/sereal">
    <_comment>Sereal binary serialization format</_comment>
    <tika:link>https://github.com/Sereal/Sereal/blob/master/sereal_spec.pod</tika:link>
    <glob pattern="*.srl"/>
  </mime-type>
  <mime-type type="application/sereal;version=1">
    <sub-class-of type="application/sereal"/>
    <magic priority="50">

- Implemented API streaming for the `watch-cache`
  
  When `sendInitialEvents` `ListOption` is set together with `watch=true`, it begins the watch stream with synthetic init events followed by a synthetic "Bookmark" after which the server continues streaming events. ([#110960](https://github.com/kubernetes/kubernetes/pull/110960), [@p0lyn0mial](https://github.com/p0lyn0mial))

- github.com/shirou/gopsutil: c95755e
- github.com/shirou/w32: bb4de01
- github.com/shurcooL/go-goon: 37c2f52
- github.com/shurcooL/go: 9e1955d
- github.com/sourcegraph/go-diff: v0.5.1
- github.com/tarm/serial: 98f6abe
- github.com/tidwall/pretty: v1.0.0
- github.com/timakin/bodyclose: 87058b9
- github.com/ultraware/funlen: v0.0.2
- github.com/urfave/cli: v1.20.0
- github.com/valyala/bytebufferpool: v1.0.0

- kubeadm: improved the overall logic, error handling, and output messages when waiting for the kubelet and API server `/healthz` endpoints to return `OK`. The kubelet and API server checks no longer ran in parallel, but one after another (in serial).
   ([#121958](https://github.com/kubernetes/kubernetes/pull/121958), [@neolit123](https://github.com/neolit123))

* Fixed an issue ([#47800](https://github.com/kubernetes/kubernetes/pull/47800)) where `kubectl logs -f` failed with `unexpected stream type ""`. ([#51872](https://github.com/kubernetes/kubernetes/pull/51872), [@feiskyer](https://github.com/feiskyer))

- Implemented API for streaming for the `etcd` store implementation.
  When `sendInitialEvents ListOption` is set together with `watch=true`, it begins the watch stream with synthetic init events followed by a synthetic `Bookmark`, after which the server continues streaming events. ([#119557](https://github.com/kubernetes/kubernetes/pull/119557), [@p0lyn0mial](https://github.com/p0lyn0mial))

  - The `export` query parameter for list API calls, deprecated since v1.14, will be removed in v1.18.
  - The `series.state` field in the events.k8s.io/v1beta1 Event API is deprecated and will be removed in v1.18 ([#75987](https://github.com/kubernetes/kubernetes/pull/75987), [@yastij](https://github.com/yastij))

- kubeadm

- Update the Event series starting count when emitting isomorphic events from 1 to 2. ([#119375](https://github.com/kubernetes/kubernetes/pull/119375), [@dgrisonnet](https://github.com/dgrisonnet)) [SIG API Machinery and Testing]

## Dependencies

- Ubuntu 18.04 (Bionic) series has been added to Juju charms ([#65644](https://github.com/kubernetes/kubernetes/pull/65644), [@tvansteenburgh](https://github.com/tvansteenburgh))