github.com/envoyproxy/go-control-plane/envoy v1.32.2: v3.Cluster

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/cluster/v3.Cluster in pkg:golang/github.com/envoyproxy/go-control-plane/envoy@v1.32.2
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/envoyproxy/go-control-plane/envoy@v1.32.2
Demonstrate these symbols/APIs:
  - github.com/envoyproxy/go-control-plane/envoy/config/cluster/v3.Cluster

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:sha256:7a8f36cf81dd13896558d53602e166b4ff6b9f3092029d722b1bf2684bc8b210","contract":["envoy Cluster v3 message initializes with valid discovery type, connect timeout, and endpoint socket address"],"goal":"verify github.com/envoyproxy/go-control-plane/envoy/config/cluster/v3.Cluster in pkg:golang/github.com/envoyproxy/go-control-plane/envoy@v1.32.2","kind":"HOW","packages":["pkg:golang/github.com/envoyproxy/go-control-plane/envoy@v1.32.2"],"schemaVersion":1,"symbols":["github.com/envoyproxy/go-control-plane/envoy/config/cluster/v3.Cluster"]},"contractCommand":["go","run","./test"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"golang","libc":"glibc","libcVersion":"2.39","os":"linux","osVersionBucket":"24","packageManager":"go","schemaVersion":1},"license":"MIT-0","packages":["pkg:golang/github.com/envoyproxy/go-control-plane/envoy@v1.32.2"],"schemaVersion":1,"subject":"pkg:golang/github.com/envoyproxy/go-control-plane/envoy@v1.32.2","symbols":["github.com/envoyproxy/go-control-plane/envoy/config/cluster/v3.Cluster"],"verifierAdapter":"golang@1"}

module sample

go 1.23.0

require (
	github.com/envoyproxy/go-control-plane/envoy v1.32.2
	google.golang.org/protobuf v1.35.2
)

require (
	github.com/cncf/xds/go v0.0.0-20240723142845-024c85f92f20 // indirect
	github.com/envoyproxy/protoc-gen-validate v1.1.0 // indirect
	github.com/planetscale/vtprotobuf v0.6.1-0.20240319094008-0393e58bdf10 // indirect
)

github.com/cncf/xds/go v0.0.0-20240723142845-024c85f92f20 h1:N+3sFI5GUjRKBi+i0TxYVST9h4Ie192jJWpHvthBBgg=
github.com/cncf/xds/go v0.0.0-20240723142845-024c85f92f20/go.mod h1:W+zGtBO5Y1IgJhy4+A9GOqVhqLpfZi+vwmdNXUehLA8=
github.com/envoyproxy/go-control-plane/envoy v1.32.2 h1:zidqwmijfcbyKqVxjQDFx042PgX+p9U+/fu/f9VtSk8=
github.com/envoyproxy/go-control-plane/envoy v1.32.2/go.mod h1:eR2SOX2IedqlPvmiKjUH7Wu//S602JKI7HPC/L3SRq8=
github.com/envoyproxy/protoc-gen-validate v1.1.0 h1:tntQDh69XqOCOZsDz0lVJQez/2L6Uu2PdjCQwWCJ3bM=
github.com/envoyproxy/protoc-gen-validate v1.1.0/go.mod h1:sXRDRVmzEbkM7CVcM06s9shE/m23dg3wzjl0UWqJ2q4=
github.com/google/go-cmp v0.5.5 h1:Khx7svrCpmxxtHBq5j2mp/xVjsi8hQMfNLvJFAlrGgU=
github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
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=
golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=
golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
google.golang.org/protobuf v1.35.2 h1:8Ar7bF+apOIoThw1EdZl0p1oWvMqTHmpA2fRTyZO8io=
google.golang.org/protobuf v1.35.2/go.mod h1:9fA7Ob0pmnwhb644+1+CVWFRbNajQ6iRojtC/QF5bRE=

{
  "schemaVersion": 1,
  "goal": "verify github.com/envoyproxy/go-control-plane/envoy/config/cluster/v3.Cluster in pkg:golang/github.com/envoyproxy/go-control-plane/envoy@v1.32.2",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/envoyproxy/go-control-plane/envoy@v1.32.2"
  ],
  "symbols": [
    "github.com/envoyproxy/go-control-plane/envoy/config/cluster/v3.Cluster"
  ]
}

package main

import (
	"fmt"
	"time"

	clusterv3 "github.com/envoyproxy/go-control-plane/envoy/config/cluster/v3"
	corev3 "github.com/envoyproxy/go-control-plane/envoy/config/core/v3"
	endpointv3 "github.com/envoyproxy/go-control-plane/envoy/config/endpoint/v3"
	"google.golang.org/protobuf/types/known/durationpb"
)

func main() {
	cluster := &clusterv3.Cluster{
		Name:                 "service_backend",
		ConnectTimeout:       durationpb.New(5 * time.Second),
		ClusterDiscoveryType: &clusterv3.Cluster_Type{Type: clusterv3.Cluster_LOGICAL_DNS},
		DnsLookupFamily:      clusterv3.Cluster_V4_ONLY,
		LbPolicy:             clusterv3.Cluster_ROUND_ROBIN,
		LoadAssignment: &endpointv3.ClusterLoadAssignment{
			ClusterName: "service_backend",
			Endpoints: []*endpointv3.LocalityLbEndpoints{
				{
					LbEndpoints: []*endpointv3.LbEndpoint{
						{
							HostIdentifier: &endpointv3.LbEndpoint_Endpoint{
								Endpoint: &endpointv3.Endpoint{
									Address: &corev3.Address{
										Address: &corev3.Address_SocketAddress{
											SocketAddress: &corev3.SocketAddress{
												Protocol: corev3.SocketAddress_TCP,
												Address:  "127.0.0.1",
												PortSpecifier: &corev3.SocketAddress_PortValue{
													PortValue: 8080,
												},
											},
										},
									},
								},
							},
						},
					},
				},
			},
		},
	}

	if cluster.GetName() != "service_backend" {
		panic("expected cluster name service_backend")
	}
	if cluster.GetConnectTimeout().GetSeconds() != 5 {
		panic("expected connect timeout 5 seconds")
	}
	if cluster.GetLbPolicy() != clusterv3.Cluster_ROUND_ROBIN {
		panic("expected round robin lb policy")
	}

	endpoints := cluster.GetLoadAssignment().GetEndpoints()
	if len(endpoints) != 1 {
		panic("expected 1 locality lb endpoint")
	}
	lbEndpoints := endpoints[0].GetLbEndpoints()
	if len(lbEndpoints) != 1 {
		panic("expected 1 lb endpoint")
	}
	sockAddr := lbEndpoints[0].GetEndpoint().GetAddress().GetSocketAddress()
	if sockAddr.GetAddress() != "127.0.0.1" || sockAddr.GetPortValue() != 8080 {
		panic("expected socket address 127.0.0.1:8080")
	}

	fmt.Println("PASS: Envoy Cluster v3 verification successful")
}