Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Add multi-container probing #14853

Merged
merged 2 commits into from
Mar 12, 2024
Merged

Add multi-container probing #14853

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
2fa7749
Add multi-container probing
ReToCode Jan 30, 2024
7b30193
Add e2e test for multi container probing
ReToCode Feb 1, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Jump to
Jump to file
Failed to load files.
Diff view
Diff view
10 changes: 8 additions & 2 deletions config/core/configmaps/features.yaml
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -22,7 +22,7 @@ metadata:
app.kubernetes.io/component: controller
app.kubernetes.io/version: devel
annotations:
knative.dev/example-checksum: "f2fc138e"
knative.dev/example-checksum: "632d47dd"
data:
_example: |-
################################
Expand Down Expand Up @@ -50,9 +50,15 @@ data:
# Indicates whether multi container support is enabled
#
# WARNING: Cannot safely be disabled once enabled.
# See: https://knative.dev/docs/serving/feature-flags/#multi-containers
# See: https://knative.dev/docs/serving/configuration/feature-flags/#multiple-containers
multi-container: "enabled"

# Indicates whether multi container probing is enabled
#
# WARNING: Cannot safely be disabled once enabled.
# See: https://knative.dev/docs/serving/configuration/feature-flags/#multiple-container-probing
multi-container-probing: "disabled"
Copy link
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I think we might not just want to enable this when multi-container is enabled, as it will change the QP spec (array instead of single probe) which causes a redeploy of all Knative Services, thus a new flag.

Copy link
Contributor

@skonto skonto Feb 5, 2024 •
edited

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Also it is a good idea for people to test this and then we should remove the flag once this is mature enough. We need to add this to the docs under https://knative.dev/docs/serving/configuration/feature-flags.

Copy link
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Added docs in knative/docs#5855


# Indicates whether Kubernetes affinity support is enabled
#
# WARNING: Cannot safely be disabled once enabled.
Expand Down
3 changes: 3 additions & 0 deletions pkg/apis/config/features.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -54,6 +54,7 @@ const (
func defaultFeaturesConfig() *Features {
return &Features{
MultiContainer: Enabled,
MultiContainerProbing: Disabled,
PodSpecAffinity: Disabled,
PodSpecTopologySpreadConstraints: Disabled,
PodSpecDryRun: Allowed,
Expand Down Expand Up @@ -87,6 +88,7 @@ func NewFeaturesConfigFromMap(data map[string]string) (*Features, error) {

if err := cm.Parse(data,
asFlag("multi-container", &nc.MultiContainer),
asFlag("multi-container-probing", &nc.MultiContainerProbing),
asFlag("kubernetes.podspec-affinity", &nc.PodSpecAffinity),
asFlag("kubernetes.podspec-topologyspreadconstraints", &nc.PodSpecTopologySpreadConstraints),
asFlag("kubernetes.podspec-dryrun", &nc.PodSpecDryRun),
Expand Down Expand Up @@ -124,6 +126,7 @@ func NewFeaturesConfigFromConfigMap(config *corev1.ConfigMap) (*Features, error)
// Features specifies which features are allowed by the webhook.
type Features struct {
MultiContainer Flag
MultiContainerProbing Flag
PodSpecAffinity Flag
PodSpecTopologySpreadConstraints Flag
PodSpecDryRun Flag
Expand Down
20 changes: 20 additions & 0 deletions pkg/apis/config/features_test.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -60,6 +60,7 @@ func TestFeaturesConfiguration(t *testing.T) {
wantErr: false,
wantFeatures: defaultWith(&Features{
MultiContainer: Enabled,
MultiContainerProbing: Enabled,
PodSpecAffinity: Enabled,
PodSpecTopologySpreadConstraints: Enabled,
PodSpecDryRun: Enabled,
Expand All @@ -79,6 +80,7 @@ func TestFeaturesConfiguration(t *testing.T) {
}),
data: map[string]string{
"multi-container": "Enabled",
"multi-container-probing": "Enabled",
"kubernetes.podspec-affinity": "Enabled",
"kubernetes.podspec-topologyspreadconstraints": "Enabled",
"kubernetes.podspec-dryrun": "Enabled",
Expand Down Expand Up @@ -114,6 +116,24 @@ func TestFeaturesConfiguration(t *testing.T) {
data: map[string]string{
"multi-container": "Disabled",
},
}, {
name: "multi-container-probing Allowed",
wantErr: false,
wantFeatures: defaultWith(&Features{
MultiContainerProbing: Allowed,
}),
data: map[string]string{
"multi-container-probing": "Allowed",
},
}, {
name: "multi-container-probing Disabled",
wantErr: false,
wantFeatures: defaultWith(&Features{
MultiContainerProbing: Disabled,
}),
data: map[string]string{
"multi-container-probing": "Disabled",
},
Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

For consistency reasons I think you need another test with name: "multi-container-probing Enabled".

Copy link
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I think we have it here

Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Typically what we have for other features is this:

 {
		name:    "kubernetes.podspec-topologyspreadconstraints Allowed",
		wantErr: false,
		wantFeatures: defaultWith(&Features{
			PodSpecTopologySpreadConstraints: Allowed,
		}),
		data: map[string]string{
			"kubernetes.podspec-topologyspreadconstraints": "Allowed",
		},
	}, {
		name:    "kubernetes.podspec-topologyspreadconstraints Enabled",
		wantErr: false,
		wantFeatures: defaultWith(&Features{
			PodSpecTopologySpreadConstraints: Enabled,
		}),
		data: map[string]string{
			"kubernetes.podspec-topologyspreadconstraints": "Enabled",
		},
	}, {
		name:    "kubernetes.podspec-topologyspreadconstraints Disabled",
		wantErr: false,
		wantFeatures: defaultWith(&Features{
			PodSpecTopologySpreadConstraints: Disabled,
		}),
		data: map[string]string{
			"kubernetes.podspec-topologyspreadconstraints": "Disabled",

Copy link
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I copied the "multi-container" one. It has only two cases. I think because it already tests Enabled in the features Enabled test. But I'm fine with adding that as well.

}, {
name: "kubernetes.podspec-affinity Allowed",
wantErr: false,
Expand Down
61 changes: 41 additions & 20 deletions pkg/apis/serving/k8s_validation.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -387,7 +387,7 @@ func ValidatePodSpec(ctx context.Context, ps corev1.PodSpec) *apis.FieldError {
case 0:
errs = errs.Also(apis.ErrMissingField("containers"))
case 1:
errs = errs.Also(ValidateContainer(ctx, ps.Containers[0], volumes, port).
errs = errs.Also(ValidateUserContainer(ctx, ps.Containers[0], volumes, port).
ViaFieldIndex("containers", 0))
default:
errs = errs.Also(validateContainers(ctx, ps.Containers, volumes, port))
Expand Down Expand Up @@ -447,7 +447,7 @@ func validateContainers(ctx context.Context, containers []corev1.Container, volu
// Note, if we allow readiness/liveness checks on sidecars, we should pass in an *empty* port here, not the main container's port.
errs = errs.Also(validateSidecarContainer(WithinSidecarContainer(ctx), containers[i], volumes).ViaFieldIndex("containers", i))
} else {
errs = errs.Also(ValidateContainer(WithinUserContainer(ctx), containers[i], volumes, port).ViaFieldIndex("containers", i))
errs = errs.Also(ValidateUserContainer(WithinUserContainer(ctx), containers[i], volumes, port).ViaFieldIndex("containers", i))
}
}
return errs
Expand Down Expand Up @@ -503,14 +503,23 @@ func validateContainersPorts(containers []corev1.Container) (corev1.ContainerPor

// validateSidecarContainer validate fields for non serving containers
func validateSidecarContainer(ctx context.Context, container corev1.Container, volumes map[string]corev1.Volume) (errs *apis.FieldError) {
if container.LivenessProbe != nil {
errs = errs.Also(apis.CheckDisallowedFields(*container.LivenessProbe,
*ProbeMask(&corev1.Probe{})).ViaField("livenessProbe"))
}
if container.ReadinessProbe != nil {
errs = errs.Also(apis.CheckDisallowedFields(*container.ReadinessProbe,
*ProbeMask(&corev1.Probe{})).ViaField("readinessProbe"))
cfg := config.FromContextOrDefaults(ctx)
if cfg.Features.MultiContainerProbing != config.Enabled {
if container.LivenessProbe != nil {
errs = errs.Also(apis.CheckDisallowedFields(*container.LivenessProbe,
*ProbeMask(&corev1.Probe{})).ViaField("livenessProbe"))
}
if container.ReadinessProbe != nil {
errs = errs.Also(apis.CheckDisallowedFields(*container.ReadinessProbe,
*ProbeMask(&corev1.Probe{})).ViaField("readinessProbe"))
}
} else if cfg.Features.MultiContainerProbing == config.Enabled {
// Liveness Probes
errs = errs.Also(validateProbe(container.LivenessProbe, nil, false).ViaField("livenessProbe"))
// Readiness Probes
errs = errs.Also(validateReadinessProbe(container.ReadinessProbe, nil, false).ViaField("readinessProbe"))
}

return errs.Also(validate(ctx, container, volumes))
}

Expand Down Expand Up @@ -544,12 +553,12 @@ func validateInitContainer(ctx context.Context, container corev1.Container, volu
return errs.Also(validate(WithinInitContainer(ctx), container, volumes))
}

// ValidateContainer validate fields for serving containers
func ValidateContainer(ctx context.Context, container corev1.Container, volumes map[string]corev1.Volume, port corev1.ContainerPort) (errs *apis.FieldError) {
// ValidateUserContainer validate fields for serving containers
func ValidateUserContainer(ctx context.Context, container corev1.Container, volumes map[string]corev1.Volume, port corev1.ContainerPort) (errs *apis.FieldError) {
// Liveness Probes
errs = errs.Also(validateProbe(container.LivenessProbe, port).ViaField("livenessProbe"))
errs = errs.Also(validateProbe(container.LivenessProbe, &port, true).ViaField("livenessProbe"))
Copy link
Contributor

@skonto skonto Feb 5, 2024 •
edited

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

You could also pass context to validateProbe and define a simple func IsUserContainer(ctx). We use that pattern elsewhere in this file. In this case it is simple to pass the flag but in general it might be better in cases where we have multiple conditions. 🤔

Copy link
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Yeah, maybe a bit overkill here for one private only bool param 🤷

// Readiness Probes
errs = errs.Also(validateReadinessProbe(container.ReadinessProbe, port).ViaField("readinessProbe"))
errs = errs.Also(validateReadinessProbe(container.ReadinessProbe, &port, true).ViaField("readinessProbe"))
return errs.Also(validate(ctx, container, volumes))
}

Expand Down Expand Up @@ -751,12 +760,12 @@ func validateContainerPortBasic(port corev1.ContainerPort) *apis.FieldError {
return errs
}

func validateReadinessProbe(p *corev1.Probe, port corev1.ContainerPort) *apis.FieldError {
func validateReadinessProbe(p *corev1.Probe, port *corev1.ContainerPort, isUserContainer bool) *apis.FieldError {
if p == nil {
return nil
}

errs := validateProbe(p, port)
errs := validateProbe(p, port, isUserContainer)

if p.PeriodSeconds < 0 {
errs = errs.Also(apis.ErrOutOfBoundsValue(p.PeriodSeconds, 0, math.MaxInt32, "periodSeconds"))
Expand Down Expand Up @@ -798,7 +807,7 @@ func validateReadinessProbe(p *corev1.Probe, port corev1.ContainerPort) *apis.Fi
return errs
}

func validateProbe(p *corev1.Probe, port corev1.ContainerPort) *apis.FieldError {
func validateProbe(p *corev1.Probe, port *corev1.ContainerPort, isUserContainer bool) *apis.FieldError {
Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

There are a few functions we could use to do some early checking from "k8s.io/apimachinery/pkg/util/validation", we already import that:

	validation.IsValidPortNum()
	validation.IsValidPortName()

validation is the same pkg K8s project uses to do validation. So I am wondering if we want to fail fast and if so which part of the logic here: https://github.com/kubernetes/kubernetes/blob/master/pkg/apis/core/validation/validation.go#L3057 we want to re-use or copy.

Copy link
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Probably better addressed in a separate issue/PR? This one is about adding the same logic to multiple containers. When we use K8s functionality, we change also the existing validation.

Copy link
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

#14774

ReToCode marked this conversation as resolved.
Show resolved Hide resolved
if p == nil {
return nil
}
Expand All @@ -813,16 +822,28 @@ func validateProbe(p *corev1.Probe, port corev1.ContainerPort) *apis.FieldError
handlers = append(handlers, "httpGet")
errs = errs.Also(apis.CheckDisallowedFields(*h.HTTPGet, *HTTPGetActionMask(h.HTTPGet))).ViaField("httpGet")
getPort := h.HTTPGet.Port
if getPort.StrVal != "" && getPort.StrVal != port.Name {
errs = errs.Also(apis.ErrInvalidValue(getPort.String(), "httpGet.port", "Probe port must match container port"))
if isUserContainer {
if getPort.StrVal != "" && getPort.StrVal != port.Name {
errs = errs.Also(apis.ErrInvalidValue(getPort.String(), "httpGet.port", "Probe port must match container port"))
}
} else {
if getPort.StrVal == "" && getPort.IntVal == 0 {
errs = errs.Also(apis.ErrInvalidValue(getPort.String(), "httpGet.port", "Probe port must be specified"))
}
}
}
if h.TCPSocket != nil {
handlers = append(handlers, "tcpSocket")
errs = errs.Also(apis.CheckDisallowedFields(*h.TCPSocket, *TCPSocketActionMask(h.TCPSocket))).ViaField("tcpSocket")
tcpPort := h.TCPSocket.Port
if tcpPort.StrVal != "" && tcpPort.StrVal != port.Name {
errs = errs.Also(apis.ErrInvalidValue(tcpPort.String(), "tcpSocket.port", "Probe port must match container port"))
if isUserContainer {
if tcpPort.StrVal != "" && tcpPort.StrVal != port.Name {
errs = errs.Also(apis.ErrInvalidValue(tcpPort.String(), "tcpSocket.port", "Probe port must match container port"))
}
} else {
if tcpPort.StrVal == "" && tcpPort.IntVal == 0 {
errs = errs.Also(apis.ErrInvalidValue(tcpPort.String(), "tcpSocket.port", "Probe port must be specified"))
}
}
}
if h.Exec != nil {
Expand Down