github.com/cncf/xds/go v0.0.0-20250501225837-2ac532fd4443: v3.ResourceLocator_Scheme_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/cncf/xds/go/xds/core/v3.ResourceLocator_Scheme_value in pkg:golang/github.com/cncf/xds/go@v0.0.0-20250501225837-2ac532fd4443
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/cncf/xds/go@v0.0.0-20250501225837-2ac532fd4443
Demonstrate these symbols/APIs:
  - github.com/cncf/xds/go/xds/core/v3.ResourceLocator_Scheme_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:sha256:7f6e6f7539e3a7419a0c63d95f37d0d380d9c5ad1461e53320763f6c17de418d","contract":["ResourceLocator_Scheme_value maps canonical xDS resource locator scheme enum names to their defined int32 numerical values","ResourceLocator_Scheme_value maps XDSTP to 0, HTTP to 1, and FILE to 2","ResourceLocator_Scheme_value contains exactly 3 scheme mappings matching ResourceLocator_Scheme_name inverses","ResourceLocator_Scheme_value int32 values cast to ResourceLocator_Scheme match canonical enum constants","ResourceLocator_Scheme_value lookup for unknown scheme returns zero and false in comma-ok check","ResourceLocator message Scheme can be configured using scheme resolved from ResourceLocator_Scheme_value"],"goal":"verify github.com/cncf/xds/go/xds/core/v3.ResourceLocator_Scheme_value in pkg:golang/github.com/cncf/xds/go@v0.0.0-20250501225837-2ac532fd4443","kind":"HOW","packages":["pkg:golang/github.com/cncf/xds/go@v0.0.0-20250501225837-2ac532fd4443"],"schemaVersion":1,"symbols":["github.com/cncf/xds/go/xds/core/v3.ResourceLocator_Scheme_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/cncf/xds/go@v0.0.0-20250501225837-2ac532fd4443"],"schemaVersion":1,"subject":"pkg:golang/github.com/cncf/xds/go@v0.0.0-20250501225837-2ac532fd4443","symbols":["github.com/cncf/xds/go/xds/core/v3.ResourceLocator_Scheme_value"],"verifierAdapter":"golang@1"}

module sample

go 1.26.6

require github.com/cncf/xds/go v0.0.0-20250501225837-2ac532fd4443

require (
	github.com/envoyproxy/protoc-gen-validate v1.0.4 // indirect
	google.golang.org/protobuf v1.33.0 // indirect
)

github.com/cncf/xds/go v0.0.0-20250501225837-2ac532fd4443 h1:aQ3y1lwWyqYPiWZThqv1aFbZMiM9vblcSArJRf2Irls=
github.com/cncf/xds/go v0.0.0-20250501225837-2ac532fd4443/go.mod h1:W+zGtBO5Y1IgJhy4+A9GOqVhqLpfZi+vwmdNXUehLA8=
github.com/envoyproxy/protoc-gen-validate v1.0.4 h1:gVPz/FMfvh57HdSJQyvBtF00j8JU4zdyUgIUNhlgg0A=
github.com/envoyproxy/protoc-gen-validate v1.0.4/go.mod h1:qys6tmnRsYrQqIhm2bvKZH4Blx/1gTIZ2UKVY1M+Yew=
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=
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 v1.33.0 h1:uNO2rsAINq/JlFpSdYEKIZ0uKD/R9cpdv0T+yoGwGmI=
google.golang.org/protobuf v1.33.0/go.mod h1:c6P6GXX6sHbq/GpV6MGZEdwhWPcYBgnhAHhKbcUYpos=

package main

import (
	"fmt"

	corev3 "github.com/cncf/xds/go/xds/core/v3"
)

func main() {
	schemeNames := []string{"XDSTP", "HTTP", "FILE"}
	for _, name := range schemeNames {
		if val, ok := corev3.ResourceLocator_Scheme_value[name]; ok {
			scheme := corev3.ResourceLocator_Scheme(val)
			locator := &corev3.ResourceLocator{
				Scheme:    scheme,
				Id:        "resource-1",
				Authority: "example.com",
			}
			fmt.Printf("Scheme %s: %d (%s), locator scheme: %s\n", name, val, scheme, locator.GetScheme())
		}
	}
}

{
  "schemaVersion": 1,
  "goal": "verify github.com/cncf/xds/go/xds/core/v3.ResourceLocator_Scheme_value in pkg:golang/github.com/cncf/xds/go@v0.0.0-20250501225837-2ac532fd4443",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/cncf/xds/go@v0.0.0-20250501225837-2ac532fd4443"
  ],
  "symbols": [
    "github.com/cncf/xds/go/xds/core/v3.ResourceLocator_Scheme_value"
  ]
}

package main

import (
	"fmt"
	"os"

	corev3 "github.com/cncf/xds/go/xds/core/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. ResourceLocator_Scheme_value maps canonical xDS resource locator scheme enum names to their defined int32 numerical values
	if corev3.ResourceLocator_Scheme_value == nil {
		return fmt.Errorf("ResourceLocator_Scheme_value is nil")
	}

	// 2. ResourceLocator_Scheme_value maps XDSTP to 0, HTTP to 1, and FILE to 2
	expectedValues := map[string]int32{
		"XDSTP": 0,
		"HTTP":  1,
		"FILE":  2,
	}

	for name, expected := range expectedValues {
		val, ok := corev3.ResourceLocator_Scheme_value[name]
		if !ok {
			return fmt.Errorf("ResourceLocator_Scheme_value missing expected key %q", name)
		}
		if val != expected {
			return fmt.Errorf("ResourceLocator_Scheme_value[%q] = %d; want %d", name, val, expected)
		}
	}

	// 3. ResourceLocator_Scheme_value contains exactly 3 scheme mappings matching ResourceLocator_Scheme_name inverses
	if len(corev3.ResourceLocator_Scheme_value) != 3 {
		return fmt.Errorf("expected 3 entries in ResourceLocator_Scheme_value, got %d", len(corev3.ResourceLocator_Scheme_value))
	}
	for name, val := range corev3.ResourceLocator_Scheme_value {
		mappedName, ok := corev3.ResourceLocator_Scheme_name[val]
		if !ok {
			return fmt.Errorf("ResourceLocator_Scheme_name has no entry for value %d (%s)", val, name)
		}
		if mappedName != name {
			return fmt.Errorf("ResourceLocator_Scheme_name[%d] = %q; want %q", val, mappedName, name)
		}
	}

	// 4. ResourceLocator_Scheme_value int32 values cast to ResourceLocator_Scheme match canonical enum constants
	enumChecks := []struct {
		name     string
		expected corev3.ResourceLocator_Scheme
	}{
		{"XDSTP", corev3.ResourceLocator_XDSTP},
		{"HTTP", corev3.ResourceLocator_HTTP},
		{"FILE", corev3.ResourceLocator_FILE},
	}

	for _, check := range enumChecks {
		val, ok := corev3.ResourceLocator_Scheme_value[check.name]
		if !ok {
			return fmt.Errorf("ResourceLocator_Scheme_value missing key %q during enum check", check.name)
		}
		if corev3.ResourceLocator_Scheme(val) != check.expected {
			return fmt.Errorf("ResourceLocator_Scheme(ResourceLocator_Scheme_value[%q]) = %v; want %v", check.name, corev3.ResourceLocator_Scheme(val), check.expected)
		}
	}

	// 5. ResourceLocator_Scheme_value lookup for unknown scheme returns zero and false in comma-ok check
	if val, ok := corev3.ResourceLocator_Scheme_value["UNKNOWN_SCHEME"]; ok || val != 0 {
		return fmt.Errorf("ResourceLocator_Scheme_value lookup for nonexistent key returned val=%d, ok=%v; want 0, false", val, ok)
	}

	// 6. ResourceLocator message Scheme can be configured using scheme resolved from ResourceLocator_Scheme_value
	xdstpVal, ok := corev3.ResourceLocator_Scheme_value["XDSTP"]
	if !ok {
		return fmt.Errorf("ResourceLocator_Scheme_value missing XDSTP")
	}
	locator := &corev3.ResourceLocator{
		Scheme:    corev3.ResourceLocator_Scheme(xdstpVal),
		Id:        "example-id",
		Authority: "example.com",
	}
	if locator.GetScheme() != corev3.ResourceLocator_XDSTP {
		return fmt.Errorf("locator.GetScheme() = %v; want %v", locator.GetScheme(), corev3.ResourceLocator_XDSTP)
	}

	return nil
}