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

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_DiscoveryType_value 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/cluster/v3.Cluster_DiscoveryType_value

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:sha256:6c3ee25aeb9f1a22a345f10c53db0b495446b8ae9b15cf846b48701ebf3f0ae2","contract":["Cluster_DiscoveryType_value maps canonical Envoy discovery type enum names to their defined int32 numerical values","Cluster_DiscoveryType_value maps STATIC to 0, STRICT_DNS to 1, LOGICAL_DNS to 2, EDS to 3, and ORIGINAL_DST to 4","Cluster_DiscoveryType_value contains exactly 5 discovery type mappings matching Cluster_DiscoveryType_name inverses","Cluster_DiscoveryType_value int32 values cast to Cluster_DiscoveryType match canonical enum constants","Cluster_DiscoveryType_value lookup for unknown discovery type returns zero and false in comma-ok check","Cluster message ClusterDiscoveryType can be configured using discovery type resolved from Cluster_DiscoveryType_value"],"goal":"verify github.com/envoyproxy/go-control-plane/envoy/config/cluster/v3.Cluster_DiscoveryType_value 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/cluster/v3.Cluster_DiscoveryType_value"]},"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/cluster/v3.Cluster_DiscoveryType_value"],"verifierAdapter":"golang@1"}

module sample

go 1.24.0

require github.com/envoyproxy/go-control-plane/envoy v1.37.0

require (
	cel.dev/expr v0.24.0 // indirect
	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
	google.golang.org/genproto/googleapis/api v0.0.0-20251029180050-ab9386a59fda // indirect
	google.golang.org/genproto/googleapis/rpc v0.0.0-20251029180050-ab9386a59fda // indirect
	google.golang.org/protobuf v1.36.11 // indirect
)

cel.dev/expr v0.24.0 h1:56OvJKSH3hDGL0ml5uSxZmz3/3Pq4tJ+fb1unVLAFcY=
cel.dev/expr v0.24.0/go.mod h1:hLPLo1W4QUmuYdA72RBX06QTs6MXw941piREPl3Yfiw=
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/genproto/googleapis/api v0.0.0-20251029180050-ab9386a59fda h1:+2XxjfsAu6vqFxwGBRcHiMaDCuZiqXGDUDVWVtrFAnE=
google.golang.org/genproto/googleapis/api v0.0.0-20251029180050-ab9386a59fda/go.mod h1:fDMmzKV90WSg1NbozdqrE64fkuTv6mlq2zxo9ad+3yo=
google.golang.org/genproto/googleapis/rpc v0.0.0-20251029180050-ab9386a59fda h1:i/Q+bfisr7gq6feoJnS/DlpdwEL4ihp41fvRiM3Ork0=
google.golang.org/genproto/googleapis/rpc v0.0.0-20251029180050-ab9386a59fda/go.mod h1:7i2o+ce6H/6BluujYR+kqX3GKH+dChPTQU19wjRPiGk=
google.golang.org/protobuf v1.36.11 h1:fV6ZwhNocDyBLK0dj+fg8ektcVegBBuEolpbTQyBNVE=
google.golang.org/protobuf v1.36.11/go.mod h1:HTf+CrKn2C3g5S8VImy6tdcUvCska2kB7j23XfzDpco=

package main

import (
	"fmt"

	clusterv3 "github.com/envoyproxy/go-control-plane/envoy/config/cluster/v3"
)

func main() {
	discoveryTypeNames := []string{"STATIC", "STRICT_DNS", "LOGICAL_DNS", "EDS", "ORIGINAL_DST"}
	for _, name := range discoveryTypeNames {
		if val, ok := clusterv3.Cluster_DiscoveryType_value[name]; ok {
			enumVal := clusterv3.Cluster_DiscoveryType(val)
			fmt.Printf("%s: %d (%s)\n", name, val, enumVal)
		}
	}
}

{
  "schemaVersion": 1,
  "goal": "verify github.com/envoyproxy/go-control-plane/envoy/config/cluster/v3.Cluster_DiscoveryType_value 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/cluster/v3.Cluster_DiscoveryType_value"
  ]
}

package main

import (
	"fmt"
	"os"

	clusterv3 "github.com/envoyproxy/go-control-plane/envoy/config/cluster/v3"
)

func main() {
	if err := runContract(); err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: %v\n", err)
		os.Exit(1)
	}
	fmt.Println("PASS: all contract assertions satisfied")
}

func runContract() error {
	// 1. Cluster_DiscoveryType_value maps canonical Envoy discovery type enum names to their defined int32 numerical values
	if clusterv3.Cluster_DiscoveryType_value == nil {
		return fmt.Errorf("Cluster_DiscoveryType_value is nil")
	}

	// 2. Cluster_DiscoveryType_value maps STATIC to 0, STRICT_DNS to 1, LOGICAL_DNS to 2, EDS to 3, and ORIGINAL_DST to 4
	expectedValues := map[string]int32{
		"STATIC":       0,
		"STRICT_DNS":   1,
		"LOGICAL_DNS":  2,
		"EDS":          3,
		"ORIGINAL_DST": 4,
	}

	for name, expected := range expectedValues {
		val, ok := clusterv3.Cluster_DiscoveryType_value[name]
		if !ok {
			return fmt.Errorf("Cluster_DiscoveryType_value missing expected key %q", name)
		}
		if val != expected {
			return fmt.Errorf("Cluster_DiscoveryType_value[%q] = %d; want %d", name, val, expected)
		}
	}

	// 3. Cluster_DiscoveryType_value contains exactly 5 discovery type mappings matching Cluster_DiscoveryType_name inverses
	if len(clusterv3.Cluster_DiscoveryType_value) != 5 {
		return fmt.Errorf("expected 5 entries in Cluster_DiscoveryType_value, got %d", len(clusterv3.Cluster_DiscoveryType_value))
	}
	for name, val := range clusterv3.Cluster_DiscoveryType_value {
		mappedName, ok := clusterv3.Cluster_DiscoveryType_name[val]
		if !ok {
			return fmt.Errorf("Cluster_DiscoveryType_name has no entry for value %d (%s)", val, name)
		}
		if mappedName != name {
			return fmt.Errorf("Cluster_DiscoveryType_name[%d] = %q; want %q", val, mappedName, name)
		}
	}

	// 4. Cluster_DiscoveryType_value int32 values cast to Cluster_DiscoveryType match canonical enum constants
	enumChecks := []struct {
		name     string
		expected clusterv3.Cluster_DiscoveryType
	}{
		{"STATIC", clusterv3.Cluster_STATIC},
		{"STRICT_DNS", clusterv3.Cluster_STRICT_DNS},
		{"LOGICAL_DNS", clusterv3.Cluster_LOGICAL_DNS},
		{"EDS", clusterv3.Cluster_EDS},
		{"ORIGINAL_DST", clusterv3.Cluster_ORIGINAL_DST},
	}

	for _, check := range enumChecks {
		val, ok := clusterv3.Cluster_DiscoveryType_value[check.name]
		if !ok {
			return fmt.Errorf("Cluster_DiscoveryType_value missing key %q during enum check", check.name)
		}
		if clusterv3.Cluster_DiscoveryType(val) != check.expected {
			return fmt.Errorf("Cluster_DiscoveryType(Cluster_DiscoveryType_value[%q]) = %v; want %v", check.name, clusterv3.Cluster_DiscoveryType(val), check.expected)
		}
	}

	// 5. Cluster_DiscoveryType_value lookup for unknown discovery type returns zero and false in comma-ok check
	if val, ok := clusterv3.Cluster_DiscoveryType_value["NON_EXISTENT_TYPE"]; ok || val != 0 {
		return fmt.Errorf("Cluster_DiscoveryType_value lookup for nonexistent key returned val=%d, ok=%v; want 0, false", val, ok)
	}

	// 6. Cluster message ClusterDiscoveryType can be configured using discovery type resolved from Cluster_DiscoveryType_value
	logicalDnsVal, ok := clusterv3.Cluster_DiscoveryType_value["LOGICAL_DNS"]
	if !ok {
		return fmt.Errorf("Cluster_DiscoveryType_value missing LOGICAL_DNS")
	}
	cluster := &clusterv3.Cluster{
		Name: "example_cluster",
		ClusterDiscoveryType: &clusterv3.Cluster_Type{
			Type: clusterv3.Cluster_DiscoveryType(logicalDnsVal),
		},
	}
	if cluster.GetType() != clusterv3.Cluster_LOGICAL_DNS {
		return fmt.Errorf("cluster.GetType() = %v; want %v", cluster.GetType(), clusterv3.Cluster_LOGICAL_DNS)
	}

	return nil
}