github.com/envoyproxy/go-control-plane/envoy v1.37.0: v3.GrpcService_EnvoyGrpc_

Clean-room public code sample — generation instructions

Write a brand-new, minimal, self-contained code sample in this clean-room directory.
Do not copy, paraphrase, or reference any existing project source. Work only from this spec.

A csx.json manifest scaffold already exists. Do not recreate it from memory. Preserve its case.goal, packages and symbols; fill its empty case.contract with exact assertions and correct its environment, commands and verifierAdapter for the files you generate.

Goal: verify github.com/envoyproxy/go-control-plane/envoy/config/core/v3.GrpcService_EnvoyGrpc_ in pkg:golang/github.com/envoyproxy/go-control-plane/envoy@v1.37.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/envoyproxy/go-control-plane/envoy@v1.37.0
Demonstrate these symbols/APIs:
  - github.com/envoyproxy/go-control-plane/envoy/config/core/v3.GrpcService_EnvoyGrpc_

Rules:
  - One focused purpose; the smallest project that proves the goal.
  - Include a contract test (test/contract.*) that runs OFFLINE and exits 0 exactly when the goal behavior works.
  - Pin every dependency with a lockfile so resolution is reproducible.
  - No secrets, credentials, or tokens. No real URLs (only example.com or localhost). No absolute paths.
  - No personal names, emails, company names, or project identifiers of any kind.
  - No binaries and no generated output (node_modules, dist, target, venv, .git, .env).
  - Keep it under 200 files and 256KB packed.

{"case":{"caseId":"case:sha256:c405eaf8434e5dd8acc255565a5eb7d5138c03f427cd1c1a3c8d3acb3f4e60bf","contract":["envoy GrpcService initializes with EnvoyGrpc target specifier containing cluster name and authority"],"goal":"verify github.com/envoyproxy/go-control-plane/envoy/config/core/v3.GrpcService_EnvoyGrpc_ in pkg:golang/github.com/envoyproxy/go-control-plane/envoy@v1.37.0","kind":"HOW","packages":["pkg:golang/github.com/envoyproxy/go-control-plane/envoy@v1.37.0"],"schemaVersion":1,"symbols":["github.com/envoyproxy/go-control-plane/envoy/config/core/v3.GrpcService_EnvoyGrpc_"]},"contractCommand":["go","run","./test"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"golang","language":"go","libc":"glibc","libcVersion":"2.39","os":"linux","osVersionBucket":"24","packageManager":"go","packageManagerVersion":"1.26.6","runtime":"go","runtimeVersion":"1.26.6","schemaVersion":1},"license":"MIT-0","packages":["pkg:golang/github.com/envoyproxy/go-control-plane/envoy@v1.37.0"],"schemaVersion":1,"subject":"pkg:golang/github.com/envoyproxy/go-control-plane/envoy@v1.37.0","symbols":["github.com/envoyproxy/go-control-plane/envoy/config/core/v3.GrpcService_EnvoyGrpc_"],"verifierAdapter":"golang@1"}

module sample

go 1.24.0

require (
	github.com/envoyproxy/go-control-plane/envoy v1.37.0
	google.golang.org/protobuf v1.36.11
)

require (
	github.com/cncf/xds/go v0.0.0-20251110193048-8bfbf64dc13e // indirect
	github.com/envoyproxy/protoc-gen-validate v1.3.0 // indirect
	github.com/planetscale/vtprotobuf v0.6.1-0.20240319094008-0393e58bdf10 // indirect
)

github.com/cncf/xds/go v0.0.0-20251110193048-8bfbf64dc13e h1:gt7U1Igw0xbJdyaCM5H2CnlAlPSkzrhsebQB6WQWjLA=
github.com/cncf/xds/go v0.0.0-20251110193048-8bfbf64dc13e/go.mod h1:KdCmV+x/BuvyMxRnYBlmVaq4OLiKW6iRQfvC62cvdkI=
github.com/envoyproxy/go-control-plane/envoy v1.37.0 h1:u3riX6BoYRfF4Dr7dwSOroNfdSbEPe9Yyl09/B6wBrQ=
github.com/envoyproxy/go-control-plane/envoy v1.37.0/go.mod h1:DReE9MMrmecPy+YvQOAOHNYMALuowAnbjjEMkkWOi6A=
github.com/envoyproxy/protoc-gen-validate v1.3.0 h1:TvGH1wof4H33rezVKWSpqKz5NXWg5VPuZ0uONDT6eb4=
github.com/envoyproxy/protoc-gen-validate v1.3.0/go.mod h1:HvYl7zwPa5mffgyeTUHA9zHIH36nmrm7oCbo4YKoSWA=
github.com/google/go-cmp v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8=
github.com/google/go-cmp v0.7.0/go.mod h1:pXiqmnSA92OHEEa9HXL2W4E7lf9JzCmGVUdgjX3N/iU=
github.com/planetscale/vtprotobuf v0.6.1-0.20240319094008-0393e58bdf10 h1:GFCKgmp0tecUJ0sJuv4pzYCqS9+RGSn52M3FUwPs+uo=
github.com/planetscale/vtprotobuf v0.6.1-0.20240319094008-0393e58bdf10/go.mod h1:t/avpk3KcrXxUnYOhZhMXJlSEyie6gQbtLq5NM3loB8=
google.golang.org/protobuf v1.36.11 h1:fV6ZwhNocDyBLK0dj+fg8ektcVegBBuEolpbTQyBNVE=
google.golang.org/protobuf v1.36.11/go.mod h1:HTf+CrKn2C3g5S8VImy6tdcUvCska2kB7j23XfzDpco=

{
  "schemaVersion": 1,
  "goal": "verify github.com/envoyproxy/go-control-plane/envoy/config/core/v3.GrpcService_EnvoyGrpc_ in pkg:golang/github.com/envoyproxy/go-control-plane/envoy@v1.37.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/envoyproxy/go-control-plane/envoy@v1.37.0"
  ],
  "symbols": [
    "github.com/envoyproxy/go-control-plane/envoy/config/core/v3.GrpcService_EnvoyGrpc_"
  ]
}

package main

import (
	"fmt"
	"time"

	corev3 "github.com/envoyproxy/go-control-plane/envoy/config/core/v3"
	"google.golang.org/protobuf/proto"
	"google.golang.org/protobuf/types/known/durationpb"
)

func main() {
	grpcService := &corev3.GrpcService{
		Timeout: durationpb.New(5 * time.Second),
		TargetSpecifier: &corev3.GrpcService_EnvoyGrpc_{
			EnvoyGrpc: &corev3.GrpcService_EnvoyGrpc{
				ClusterName: "backend_grpc_cluster",
				Authority:   "backend.local",
			},
		},
	}

	target, ok := grpcService.GetTargetSpecifier().(*corev3.GrpcService_EnvoyGrpc_)
	if !ok || target == nil {
		panic("expected target specifier to be *corev3.GrpcService_EnvoyGrpc_")
	}

	envoyGrpc := grpcService.GetEnvoyGrpc()
	if envoyGrpc == nil {
		panic("expected GetEnvoyGrpc() to return non-nil")
	}
	if envoyGrpc.GetClusterName() != "backend_grpc_cluster" {
		panic("expected cluster name backend_grpc_cluster")
	}
	if envoyGrpc.GetAuthority() != "backend.local" {
		panic("expected authority backend.local")
	}

	if err := grpcService.ValidateAll(); err != nil {
		panic(fmt.Sprintf("grpcService validation failed: %v", err))
	}

	data, err := proto.Marshal(grpcService)
	if err != nil {
		panic(fmt.Sprintf("proto.Marshal failed: %v", err))
	}

	decoded := &corev3.GrpcService{}
	if err := proto.Unmarshal(data, decoded); err != nil {
		panic(fmt.Sprintf("proto.Unmarshal failed: %v", err))
	}

	decodedTarget, ok := decoded.GetTargetSpecifier().(*corev3.GrpcService_EnvoyGrpc_)
	if !ok || decodedTarget == nil {
		panic("expected unmarshaled target specifier to be *corev3.GrpcService_EnvoyGrpc_")
	}
	if decoded.GetEnvoyGrpc().GetClusterName() != "backend_grpc_cluster" {
		panic("mismatched cluster name after unmarshal")
	}
	if decoded.GetEnvoyGrpc().GetAuthority() != "backend.local" {
		panic("mismatched authority after unmarshal")
	}

	fmt.Println("PASS: GrpcService_EnvoyGrpc_ verification successful")
}