Merge pull request kubernetes#126748 from SergeyKanzhelev/api_cri_readme

cri-api: readme update for 1.31

Author: k8s-ci-robot

staging/src/k8s.io/cri-api/README.md

@@ -249,6 +249,21 @@ No changes
 - [Add image_id to CRI ContainerStatus message](https://github.com/kubernetes/kubernetes/pull/123583)
   - Added `image_id` field to type `ContainerStatus`
 
+### v1.31
+
+`git diff v1.30.0 v1.31.0 -- staging/src/k8s.io/cri-api/pkg/apis/runtime/v1/api.proto`
+
+- [KEP-3619: Add NodeStatus.Features.SupplementalGroupsPolicy API and e2e](https://github.com/kubernetes/kubernetes/pull/125470)
+  - Added `features` field to the type `StatusResponse` for the runtime to kubelet handshake on what features are supported
+
+- [KEP-3619: Fine-grained SupplementalGroups control](https://github.com/kubernetes/kubernetes/pull/117842)
+  - Added `supplemental_groups_policy` field to types `LinuxContainerSecurityContext` and `LinuxSandboxSecurityContext`
+  - Added `user` field to the type `ContainerStatus` to represent actual user for the container 
+
+- [[KEP-4639] Add OCI VolumeSource CRI API](https://github.com/kubernetes/kubernetes/pull/125659)
+  - Added `image` field to the type `Mount` to represent the OCI VolumeSource 
+
+
 ## Community, discussion, contribution, and support
 
 Learn how to engage with the Kubernetes community on the [community

staging/src/k8s.io/cri-api/pkg/apis/runtime/v1/api.pb.go

@@ -601,7 +601,7 @@ message PodSandboxStatusResponse {
     map<string, string> info = 2;
     // Container statuses
     repeated ContainerStatus containers_statuses = 3;
-    // Timestamp at which container and pod statuses were recorded
+    // Timestamp in nanoseconds at which container and pod statuses were recorded
     int64 timestamp = 4;
 }
 
@@ -1344,7 +1344,7 @@ message ContainerResources {
 
 message ContainerUser {
     // User identities initially attached to first process in the Linux container.
-	// Note that the actual running identity can be changed if the process has enough privilege to do so.
+    // Note that the actual running identity can be changed if the process has enough privilege to do so.
     LinuxContainerUser linux = 1;
 
     // User identities initially attached to first process in the Windows container
@@ -1863,7 +1863,7 @@ message ContainerEventResponse {
     // Type of the container event
     ContainerEventType container_event_type = 2;
 
-    // Creation timestamp of this event
+    // Creation timestamp in nanoseconds of this event
     int64 created_at = 3;
 
     // Sandbox status
@@ -1927,7 +1927,7 @@ message Metric {
     // otherwise, it will be ignored.
     string name = 1;
     // Timestamp should be 0 if the metric was gathered live.
-    // If it was cached, the Timestamp should reflect the time it was collected.
+    // If it was cached, the Timestamp should reflect the time in nanoseconds it was collected.
     int64 timestamp = 2;
     MetricType metric_type = 3;
     // The corresponding LabelValues to the LabelKeys defined in the MetricDescriptor.