Using Gateway API 1.3.0 and its types clientset causes sigs.k8s.io/structured-merge-diff deps conflict

[pmalek]

What happened:

Importing an API package like sigs.k8s.io/gateway-api/apis/v1 and one of the typed clients e.g. sigs.k8s.io/gateway-api/pkg/client/clientset/versioned/typed/apis/v1 causes compilation errors due to conflicted sigs.k8s.io/structured-merge-diff major dependencies

go run .
# sigs.k8s.io/gateway-api/applyconfiguration/apis/v1
../../../.gvm/pkgsets/go1.25.0/global/pkg/mod/sigs.k8s.io/gateway-api@v1.3.0/applyconfiguration/apis/v1/gateway.go:74:44: cannot use internal.Parser().Type("io.k8s.sigs.gateway-api.apis.v1.Gateway") (value of struct type "sigs.k8s.io/structured-merge-diff/v4/typed".ParseableType) as "sigs.k8s.io/structured-merge-diff/v6/typed".ParseableType value in argument to managedfields.ExtractInto
../../../.gvm/pkgsets/go1.25.0/global/pkg/mod/sigs.k8s.io/gateway-api@v1.3.0/applyconfiguration/apis/v1/gatewayclass.go:73:49: cannot use internal.Parser().Type("io.k8s.sigs.gateway-api.apis.v1.GatewayClass") (value of struct type "sigs.k8s.io/structured-merge-diff/v4/typed".ParseableType) as "sigs.k8s.io/structured-merge-diff/v6/typed".ParseableType value in argument to managedfields.ExtractInto
../../../.gvm/pkgsets/go1.25.0/global/pkg/mod/sigs.k8s.io/gateway-api@v1.3.0/applyconfiguration/apis/v1/grpcroute.go:74:46: cannot use internal.Parser().Type("io.k8s.sigs.gateway-api.apis.v1.GRPCRoute") (value of struct type "sigs.k8s.io/structured-merge-diff/v4/typed".ParseableType) as "sigs.k8s.io/structured-merge-diff/v6/typed".ParseableType value in argument to managedfields.ExtractInto
../../../.gvm/pkgsets/go1.25.0/global/pkg/mod/sigs.k8s.io/gateway-api@v1.3.0/applyconfiguration/apis/v1/httproute.go:74:46: cannot use internal.Parser().Type("io.k8s.sigs.gateway-api.apis.v1.HTTPRoute") (value of struct type "sigs.k8s.io/structured-merge-diff/v4/typed".ParseableType) as "sigs.k8s.io/structured-merge-diff/v6/typed".ParseableType value in argument to managedfields.ExtractInto

What you expected to happen:

How to reproduce it (as minimally and precisely as possible):

package main

import (
	gatewayv1 "sigs.k8s.io/gateway-api/apis/v1"
	gwapiv1client "sigs.k8s.io/gateway-api/pkg/client/clientset/versioned/typed/apis/v1"
)

func main() {
	var g gatewayv1.Gateway
	_ = g
	var gwClient gwapiv1client.GatewayV1Client
	_ = gwClient
}

go.mod

module gatewayapimergediff

go 1.24.0

require sigs.k8s.io/gateway-api v1.3.0

require (
	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
	github.com/emicklei/go-restful/v3 v3.12.2 // indirect
	github.com/go-openapi/jsonpointer v0.21.0 // indirect
	github.com/go-openapi/jsonreference v0.21.0 // indirect
	github.com/go-openapi/swag v0.23.0 // indirect
	github.com/google/gnostic-models v0.7.0 // indirect
	github.com/google/uuid v1.6.0 // indirect
	github.com/josharian/intern v1.0.0 // indirect
	github.com/mailru/easyjson v0.7.7 // indirect
	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
	github.com/onsi/ginkgo/v2 v2.22.0 // indirect
	github.com/onsi/gomega v1.36.1 // indirect
	github.com/pkg/errors v0.9.1 // indirect
	go.yaml.in/yaml/v2 v2.4.2 // indirect
	go.yaml.in/yaml/v3 v3.0.4 // indirect
	golang.org/x/oauth2 v0.27.0 // indirect
	golang.org/x/sys v0.32.0 // indirect
	golang.org/x/term v0.31.0 // indirect
	golang.org/x/time v0.9.0 // indirect
	google.golang.org/protobuf v1.36.6 // indirect
	gopkg.in/evanphx/json-patch.v4 v4.12.0 // indirect
	gopkg.in/yaml.v3 v3.0.1 // indirect
	k8s.io/api v0.34.0 // indirect
	k8s.io/client-go v0.34.0 // indirect
	k8s.io/kube-openapi v0.0.0-20250710124328-f3f2b991d03b // indirect
	sigs.k8s.io/randfill v1.0.0 // indirect
	sigs.k8s.io/structured-merge-diff/v4 v4.7.0 // indirect
	sigs.k8s.io/structured-merge-diff/v6 v6.3.0 // indirect
)

require (
	github.com/fxamacker/cbor/v2 v2.9.0 // indirect
	github.com/go-logr/logr v1.4.2 // indirect
	github.com/gogo/protobuf v1.3.2 // indirect
	github.com/json-iterator/go v1.1.12 // indirect
	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
	github.com/modern-go/reflect2 v1.0.3-0.20250322232337-35a7c28c31ee // indirect
	github.com/x448/float16 v0.8.4 // indirect
	golang.org/x/net v0.39.0 // indirect
	golang.org/x/text v0.24.0 // indirect
	gopkg.in/inf.v0 v0.9.1 // indirect
	k8s.io/apimachinery v0.34.0 // indirect
	k8s.io/klog/v2 v2.130.1 // indirect
	k8s.io/utils v0.0.0-20250604170112-4c0f3b243397 // indirect
	sigs.k8s.io/json v0.0.0-20241014173422-cfa47c3a1cc8 // indirect
	sigs.k8s.io/yaml v1.6.0 // indirect
)

Anything else we need to know?:

This came up when bumping the controller-runtime dependency to v0.22.0 in Kong/kong-operator#2149 (where Gateway API is already at 1.3.0).

[ivankatliarchuk]

External DNS similar problem https://github.com/kubernetes-sigs/external-dns/actions/runs/17313615807/job/49152445856?pr=5782

Error: ../../../go/pkg/mod/github.com/openshift/client-go@v0.0.0-20230607134213-3cd0021bbee3/route/applyconfigurations/route/v1/route.go:58:42: cannot use internal.Parser().Type("com.github.openshift.api.route.v1.Route") (value of struct type "sigs.k8s.io/structured-merge-diff/v4/typed".ParseableType) as "sigs.k8s.io/structured-merge-diff/v6/typed".ParseableType value in argument to managedfields.ExtractInto
# sigs.k8s.io/gateway-api/applyconfiguration/apis/v1
Error: ../../../go/pkg/mod/sigs.k8s.io/gateway-api@v1.3.0/applyconfiguration/apis/v1/gateway.go:74:44: cannot use internal.Parser().Type("io.k8s.sigs.gateway-api.apis.v1.Gateway") (value of struct type "sigs.k8s.io/structured-merge-diff/v4/typed".ParseableType) as "sigs.k8s.io/structured-merge-diff/v6/typed".ParseableType value in argument to managedfields.ExtractInto
Error: ../../../go/pkg/mod/sigs.k8s.io/gateway-api@v1.3.0/applyconfiguration/apis/v1/gatewayclass.go:73:49: cannot use internal.Parser().Type("io.k8s.sigs.gateway-api.apis.v1.GatewayClass") (value of struct type "sigs.k8s.io/structured-merge-diff/v4/typed".ParseableType) as "sigs.k8s.io/structured-merge-diff/v6/typed".ParseableType value in argument to managedfields.ExtractInto
Error: ../../../go/pkg/mod/sigs.k8s.io/gateway-api@v1.3.0/applyconfiguration/apis/v1/grpcroute.go:74:46: cannot use internal.Parser().Type("io.k8s.sigs.gateway-api.apis.v1.GRPCRoute") (value of struct type "sigs.k8s.io/structured-merge-diff/v4/typed".ParseableType) as "sigs.k8s.io/structured-merge-diff/v6/typed".ParseableType value in argument to managedfields.ExtractInto
Error: ../../../go/pkg/mod/sigs.k8s.io/gateway-api@v1.3.0/applyconfiguration/apis/v1/httproute.go:74:46: cannot use internal.Parser().Type("io.k8s.sigs.gateway-api.apis.v1.HTTPRoute") (value of struct type "sigs.k8s.io/structured-merge-diff/v4/typed".ParseableType) as "sigs.k8s.io/structured-merge-diff/v6/typed".ParseableType value in argument to managedfields.ExtractInto

[pmalek]

It does seem like this code is generated by git@github.com:kubernetes/code-generator.git

gateway-api/applyconfiguration/internal/internal.go

Line 17 in 75aed66

// Code generated by applyconfiguration-gen. DO NOT EDIT.

And that repo has already bumped the generated code to use v6:

https://github.com/kubernetes/code-generator/blob/788f0dbcaabb293accd60eb73798d62c47f648a1/cmd/applyconfiguration-gen/generators/types.go#L34-L36

but gateway-api 1.3.0 still uses k8s.io/code-generator v0.32.3.

[youngnick]

We have two options to fix this, from what I can see:

• release a v1.3.1 patch release. We would do this normally, if it was soon after the release, but the other option is
• ensure this is fixed in the v1.4 release, which is due out in the next few weeks.

Issuing a v1.3.1 patch release means that:

• implementations using v1.3.0 MUST upgrade
• implementations MUST resubmit new conformance reports for v1.3.1 (until we close out Do Not Require Patch Version When Publishing Conformance Reports #3530 anyway)

On balance, it seems better to me to drop the patch release, but interested to hear what others think.

[pmalek]

Holding off until 1.4 means that implementations are stuck with older k8s packages (including controller-runtime etc.) which in my opinion is a rather far reaching consequence for what this issue describes.

I wasn't aware of the problem with conformance tests reports. Does that mean that until #3530 is resolved, when a patch is published in order for an implementation to be visible on gw api conformance reports page, they need to resubmit?

How we identified the culprit of that issue? How much effort would it be to solve this?

[youngnick]

Yes, right now, if we issue a patch release, implementations need to resubmit their conformance reports for that patch release. tbh I'm not sure if that's bad or not, but that's where we are.

#3530 says that we should track conformance on a minor release only, but that's not the case today. Fixing this will require changing some processes a bit, and also changing how the generation of the feature matrix page works a little. Not a big job, just work.

I think I used a bad phrasing in my previous comment - I meant to say I think we probably should do the patch release anyway, this seems serious enough to warrant it to me.

[uneet7]

Hi Team, do you know when this fix is expected to roll out?

[dfajmon]

Also encountered this on updating external-provisioner
kubernetes-csi/external-provisioner#1411

[aojea]

just asking for clarification, what seems incompatible is importing current generated code in a project that is using kubernetes 1.34 client-go, but all existing code that is using is ok, right?

[pmalek]

Using code generated under sigs.k8s.io/gateway-api/pkg/client/clientset/versioned/* + using kubernetes 1.34 (not client-go specific).

It's about sigs.k8s.io/structured-merge-diff/v6 breaking changes with respect to sigs.k8s.io/structured-merge-diff/v4 (imported now by GW API clientset).

For us the conflict is as follows:

go mod why -m sigs.k8s.io/structured-merge-diff/v4
# sigs.k8s.io/structured-merge-diff/v4
< our package >
sigs.k8s.io/gateway-api/pkg/client/clientset/versioned/typed/apis/v1
sigs.k8s.io/gateway-api/applyconfiguration/apis/v1
sigs.k8s.io/gateway-api/applyconfiguration/internal
sigs.k8s.io/structured-merge-diff/v4/typed

or

go mod why -m sigs.k8s.io/structured-merge-diff/v4
# sigs.k8s.io/structured-merge-diff/v4
< our package >
sigs.k8s.io/gateway-api/pkg/client/clientset/versioned
sigs.k8s.io/gateway-api/pkg/client/clientset/versioned/typed/apis/v1
sigs.k8s.io/gateway-api/applyconfiguration/apis/v1
sigs.k8s.io/gateway-api/applyconfiguration/internal
sigs.k8s.io/structured-merge-diff/v4/typed

vs v6 import elsewhere

go mod why -m sigs.k8s.io/structured-merge-diff/v6
# sigs.k8s.io/structured-merge-diff/v6
< our package >
k8s.io/apimachinery/pkg/runtime
sigs.k8s.io/structured-merge-diff/v6/value