google.golang.org/grpc v1.75.1: NewClient

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 grpc.NewClient in pkg:golang/google.golang.org/grpc@v1.75.1
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/google.golang.org/grpc@v1.75.1
Demonstrate these symbols/APIs:
  - grpc.NewClient

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:e8574be78675fab0791589b65d131af7aff33a07a5b2a9fcfc002b75ac926071","contract":["grpc.NewClient creates a ClientConn for a valid target when transport credentials are provided","grpc.NewClient sets Target matching the provided target URI","grpc.NewClient initializes connection in Idle connectivity state without connecting immediately","grpc.NewClient returns an error if no transport credentials or credentials bundle is configured","grpc.NewClient creates a connection that closes cleanly without error"],"goal":"verify grpc.NewClient in pkg:golang/google.golang.org/grpc@v1.75.1","kind":"HOW","packages":["pkg:golang/google.golang.org/grpc@v1.75.1"],"schemaVersion":1,"symbols":["grpc.NewClient"]},"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/google.golang.org/grpc@v1.75.1"],"schemaVersion":1,"subject":"pkg:golang/google.golang.org/grpc@v1.75.1","symbols":["grpc.NewClient"],"verifierAdapter":"golang@1"}

module sample

go 1.25.0

require google.golang.org/grpc v1.75.1

require (
	golang.org/x/net v0.58.0 // indirect
	golang.org/x/sys v0.47.0 // indirect
	golang.org/x/text v0.41.0 // indirect
	google.golang.org/genproto/googleapis/rpc v0.0.0-20260526163538-3dc84a4a5aaa // indirect
	google.golang.org/protobuf v1.36.11 // indirect
)

github.com/go-logr/logr v1.4.3 h1:CjnDlHq8ikf6E492q6eKboGOC0T8CDaOvkHCIg8idEI=
github.com/go-logr/logr v1.4.3/go.mod h1:9T104GzyrTigFIr8wt5mBrctHMim0Nb2HLGrmQ40KvY=
github.com/go-logr/stdr v1.2.2 h1:hSWxHoqTgW2S2qGc0LTAI563KZ5YKYRhT3MFKZMbjag=
github.com/go-logr/stdr v1.2.2/go.mod h1:mMo/vtBO5dYbehREoey6XUKy/eSumjCCveDpRre4VKE=
github.com/golang/protobuf v1.5.4 h1:i7eJL8qZTpSEXOPTxNKhASYpMn+8e5Q6AdndVa1dWek=
github.com/golang/protobuf v1.5.4/go.mod h1:lnTiLA8Wa4RWRcIUkrtSVa5nRhsEGBg48fD6rSs7xps=
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/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
go.opentelemetry.io/auto/sdk v1.1.0 h1:cH53jehLUN6UFLY71z+NDOiNJqDdPRaXzTel0sJySYA=
go.opentelemetry.io/auto/sdk v1.1.0/go.mod h1:3wSPjt5PWp2RhlCcmmOial7AvC4DQqZb7a7wCow3W8A=
go.opentelemetry.io/otel v1.37.0 h1:9zhNfelUvx0KBfu/gb+ZgeAfAgtWrfHJZcAqFC228wQ=
go.opentelemetry.io/otel v1.37.0/go.mod h1:ehE/umFRLnuLa/vSccNq9oS1ErUlkkK71gMcN34UG8I=
go.opentelemetry.io/otel/metric v1.37.0 h1:mvwbQS5m0tbmqML4NqK+e3aDiO02vsf/WgbsdpcPoZE=
go.opentelemetry.io/otel/metric v1.37.0/go.mod h1:04wGrZurHYKOc+RKeye86GwKiTb9FKm1WHtO+4EVr2E=
go.opentelemetry.io/otel/sdk v1.37.0 h1:ItB0QUqnjesGRvNcmAcU0LyvkVyGJ2xftD29bWdDvKI=
go.opentelemetry.io/otel/sdk v1.37.0/go.mod h1:VredYzxUvuo2q3WRcDnKDjbdvmO0sCzOvVAiY+yUkAg=
go.opentelemetry.io/otel/sdk/metric v1.37.0 h1:90lI228XrB9jCMuSdA0673aubgRobVZFhbjxHHspCPc=
go.opentelemetry.io/otel/sdk/metric v1.37.0/go.mod h1:cNen4ZWfiD37l5NhS+Keb5RXVWZWpRE+9WyVCpbo5ps=
go.opentelemetry.io/otel/trace v1.37.0 h1:HLdcFNbRQBE2imdSEgm/kwqmQj1Or1l/7bW6mxVK7z4=
go.opentelemetry.io/otel/trace v1.37.0/go.mod h1:TlgrlQ+PtQO5XFerSPUYG0JSgGyryXewPGyayAWSBS0=
golang.org/x/net v0.58.0 h1:ynWG7rqYi4ccpTEuPZ2QGWHktVEM9DMCj9yzDE0Q7To=
golang.org/x/net v0.58.0/go.mod h1:YwCddHnFlT7eLQqVprV19OnhLGtc5xOKgE0RyqgfWAU=
golang.org/x/sys v0.47.0 h1:o7XGOvZQCADBQQ4Y7VNq2dRWQR7JmOUW8Kxx4ZsNgWs=
golang.org/x/sys v0.47.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
golang.org/x/text v0.41.0 h1:vz/seA0lnX87Othu2f/0L24RcgrXD9/YFTSuGjj3rH8=
golang.org/x/text v0.41.0/go.mod h1:jvf1O8ajNzZqhSrQBPbutR/EB83Cc0CFrezNQIwbb5M=
gonum.org/v1/gonum v0.16.0 h1:5+ul4Swaf3ESvrOnidPp4GZbzf0mxVQpDCYUQE7OJfk=
gonum.org/v1/gonum v0.16.0/go.mod h1:fef3am4MQ93R2HHpKnLk4/Tbh/s0+wqD5nfa6Pnwy4E=
google.golang.org/genproto/googleapis/rpc v0.0.0-20260526163538-3dc84a4a5aaa h1:mZHHdPZl0dbGHCflZgAq/Q468DWVFcU2whhB2KAo8fk=
google.golang.org/genproto/googleapis/rpc v0.0.0-20260526163538-3dc84a4a5aaa/go.mod h1:4Hqkh8ycfw05ld/3BWL7rJOSfebL2Q+DVDeRgYgxUU8=
google.golang.org/grpc v1.75.1 h1:/ODCNEuf9VghjgO3rqLcfg8fiOP0nSluljWFlDxELLI=
google.golang.org/grpc v1.75.1/go.mod h1:JtPAzKiq4v1xcAB2hydNlWI2RnF85XXcV0mhKXr2ecQ=
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"
	"log"

	"google.golang.org/grpc"
	"google.golang.org/grpc/credentials/insecure"
)

func main() {
	conn, err := grpc.NewClient("passthrough:///localhost:50051", grpc.WithTransportCredentials(insecure.NewCredentials()))
	if err != nil {
		log.Fatalf("failed to create gRPC client: %v", err)
	}
	defer conn.Close()

	fmt.Printf("gRPC client created for target: %s\n", conn.Target())
}

{
  "schemaVersion": 1,
  "goal": "verify grpc.NewClient in pkg:golang/google.golang.org/grpc@v1.75.1",
  "kind": "HOW",
  "packages": [
    "pkg:golang/google.golang.org/grpc@v1.75.1"
  ],
  "symbols": [
    "grpc.NewClient"
  ]
}

package main

import (
	"fmt"
	"os"
	"strings"

	"google.golang.org/grpc"
	"google.golang.org/grpc/connectivity"
	"google.golang.org/grpc/credentials/insecure"
)

func main() {
	// Assertion 1: grpc.NewClient creates a ClientConn for a valid target when transport credentials are provided
	target := "passthrough:///localhost:50051"
	conn, err := grpc.NewClient(target, grpc.WithTransportCredentials(insecure.NewCredentials()))
	if err != nil {
		fmt.Fprintf(os.Stderr, "assertion 1 failed: grpc.NewClient returned error: %v\n", err)
		os.Exit(1)
	}
	if conn == nil {
		fmt.Fprintf(os.Stderr, "assertion 1 failed: expected non-nil ClientConn\n")
		os.Exit(1)
	}

	// Assertion 2: grpc.NewClient sets Target matching the provided target URI
	if gotTarget := conn.Target(); gotTarget != target {
		fmt.Fprintf(os.Stderr, "assertion 2 failed: expected target %q, got %q\n", target, gotTarget)
		os.Exit(1)
	}

	// Assertion 3: grpc.NewClient initializes connection in Idle connectivity state without connecting immediately
	if state := conn.GetState(); state != connectivity.Idle {
		fmt.Fprintf(os.Stderr, "assertion 3 failed: expected connectivity.Idle, got %v\n", state)
		os.Exit(1)
	}

	// Assertion 4: grpc.NewClient returns an error if no transport credentials or credentials bundle is configured
	_, errNoCreds := grpc.NewClient("localhost:50051")
	if errNoCreds == nil {
		fmt.Fprintf(os.Stderr, "assertion 4 failed: expected error when credentials are missing, got nil\n")
		os.Exit(1)
	}
	if !strings.Contains(errNoCreds.Error(), "no transport security set") {
		fmt.Fprintf(os.Stderr, "assertion 4 failed: unexpected error message: %v\n", errNoCreds)
		os.Exit(1)
	}

	// Assertion 5: grpc.NewClient creates a connection that closes cleanly without error
	if err := conn.Close(); err != nil {
		fmt.Fprintf(os.Stderr, "assertion 5 failed: conn.Close returned error: %v\n", err)
		os.Exit(1)
	}

	fmt.Println("All grpc.NewClient contract assertions passed successfully.")
}