google.golang.org/grpc v1.82.0

# google.golang.org/grpc Behavior

## Search Resolution

A search for existing verified solutions for `pkg:golang/google.golang.org/grpc@v1.82.0` yielded `NO_SAFE_MATCH` for this release.

## Pinned Release

- Package: `google.golang.org/grpc`
- Pinned Version: `v1.82.0`
- Manifest: `go.mod`
- Lockfile: `go.sum`

## Observed Behavior

`google.golang.org/grpc.Invoke` provides low-level unary RPC invocation over a `*grpc.ClientConn`:

1. **Unary Interceptor Execution & CallOption Metadata Capture**:
   - Calling `grpc.Invoke(ctx, method, req, reply, cc, opts...)` executes the `UnaryClientInterceptor` chain configured on the `ClientConn`.
   - Response metadata sent by the server (`grpc.SendHeader` and `grpc.SetTrailer`) is populated into `metadata.MD` variables passed via `grpc.Header(&headerMD)` and `grpc.Trailer(&trailerMD)` call options.

2. **Context Cancellation Handling**:
   - When invoked with a context that is already canceled (`ctx.Err() != nil`), `grpc.Invoke` aborts without issuing an RPC and returns an error with gRPC status code `codes.Canceled`.

3. **Closed Connection Handling**:
   - When invoked on a `*grpc.ClientConn` that has already been closed via `cc.Close()`, `grpc.Invoke` returns `grpc.ErrClientConnClosing` (wrapping a status error with `codes.Canceled`).

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 pkg:golang/google.golang.org/grpc@v1.82.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/google.golang.org/grpc@v1.82.0

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:ba4c7cf6843b8f482e0ca39d815b02b30c46ad118cb4911b948cfb906399ef62","contract":["Invoke sends a unary RPC request over a ClientConn, invoking configured unary client interceptors and capturing response header and trailer metadata passed via grpc.Header and grpc.Trailer CallOptions.","Invoke immediately returns a gRPC status error with code Canceled when invoked with an already canceled context.","Invoke returns ErrClientConnClosing when invoked on a closed ClientConn."],"goal":"verify pkg:golang/google.golang.org/grpc@v1.82.0","kind":"HOW","packages":["pkg:golang/google.golang.org/grpc@v1.82.0"],"schemaVersion":1},"contractCommand":["go","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@v1.82.0"],"schemaVersion":1,"subject":"pkg:golang/google.golang.org/grpc@v1.82.0","verifierAdapter":"golang@1"}

module sample

go 1.26.6

require (
	google.golang.org/grpc v1.82.0
	google.golang.org/protobuf v1.36.11
)

require (
	golang.org/x/net v0.53.0 // indirect
	golang.org/x/sys v0.43.0 // indirect
	golang.org/x/text v0.36.0 // indirect
	google.golang.org/genproto/googleapis/rpc v0.0.0-20260414002931-afd174a4e478 // indirect
)

github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
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 v1.2.1 h1:jXsnJ4Lmnqd11kwkBV2LgLoFMZKizbCi5fNZ/ipaZ64=
go.opentelemetry.io/auto/sdk v1.2.1/go.mod h1:KRTj+aOaElaLi+wW1kO/DZRXwkF4C5xPbEe3ZiIhN7Y=
go.opentelemetry.io/otel v1.43.0 h1:mYIM03dnh5zfN7HautFE4ieIig9amkNANT+xcVxAj9I=
go.opentelemetry.io/otel v1.43.0/go.mod h1:JuG+u74mvjvcm8vj8pI5XiHy1zDeoCS2LB1spIq7Ay0=
go.opentelemetry.io/otel/metric v1.43.0 h1:d7638QeInOnuwOONPp4JAOGfbCEpYb+K6DVWvdxGzgM=
go.opentelemetry.io/otel/metric v1.43.0/go.mod h1:RDnPtIxvqlgO8GRW18W6Z/4P462ldprJtfxHxyKd2PY=
go.opentelemetry.io/otel/sdk v1.43.0 h1:pi5mE86i5rTeLXqoF/hhiBtUNcrAGHLKQdhg4h4V9Dg=
go.opentelemetry.io/otel/sdk v1.43.0/go.mod h1:P+IkVU3iWukmiit/Yf9AWvpyRDlUeBaRg6Y+C58QHzg=
go.opentelemetry.io/otel/sdk/metric v1.43.0 h1:S88dyqXjJkuBNLeMcVPRFXpRw2fuwdvfCGLEo89fDkw=
go.opentelemetry.io/otel/sdk/metric v1.43.0/go.mod h1:C/RJtwSEJ5hzTiUz5pXF1kILHStzb9zFlIEe85bhj6A=
go.opentelemetry.io/otel/trace v1.43.0 h1:BkNrHpup+4k4w+ZZ86CZoHHEkohws8AY+WTX09nk+3A=
go.opentelemetry.io/otel/trace v1.43.0/go.mod h1:/QJhyVBUUswCphDVxq+8mld+AvhXZLhe+8WVFxiFff0=
golang.org/x/net v0.53.0 h1:d+qAbo5L0orcWAr0a9JweQpjXF19LMXJE8Ey7hwOdUA=
golang.org/x/net v0.53.0/go.mod h1:JvMuJH7rrdiCfbeHoo3fCQU24Lf5JJwT9W3sJFulfgs=
golang.org/x/sys v0.43.0 h1:Rlag2XtaFTxp19wS8MXlJwTvoh8ArU6ezoyFsMyCTNI=
golang.org/x/sys v0.43.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
golang.org/x/text v0.36.0 h1:JfKh3XmcRPqZPKevfXVpI1wXPTqbkE5f7JA92a55Yxg=
golang.org/x/text v0.36.0/go.mod h1:NIdBknypM8iqVmPiuco0Dh6P5Jcdk8lJL0CUebqK164=
gonum.org/v1/gonum v0.17.0 h1:VbpOemQlsSMrYmn7T2OUvQ4dqxQXU+ouZFQsZOx50z4=
gonum.org/v1/gonum v0.17.0/go.mod h1:El3tOrEuMpv2UdMrbNlKEh9vd86bmQ6vqIcDwxEOc1E=
google.golang.org/genproto/googleapis/rpc v0.0.0-20260414002931-afd174a4e478 h1:RmoJA1ujG+/lRGNfUnOMfhCy5EipVMyvUE+KNbPbTlw=
google.golang.org/genproto/googleapis/rpc v0.0.0-20260414002931-afd174a4e478/go.mod h1:4Hqkh8ycfw05ld/3BWL7rJOSfebL2Q+DVDeRgYgxUU8=
google.golang.org/grpc v1.82.0 h1:vguDnZUPjE26w09A63VoxZPnvPjB5Riyc0mkXPFmAIU=
google.golang.org/grpc v1.82.0/go.mod h1:yzTZ1TB1Z3SG+LIYaI+WiE8D5+PZ3ArnrSp8zF3+/ZA=
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 pkg:golang/google.golang.org/grpc@v1.82.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/google.golang.org/grpc@v1.82.0"
  ]
}

package test

import (
	"context"
	"errors"
	"net"
	"testing"
	"time"

	"google.golang.org/grpc"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/credentials/insecure"
	"google.golang.org/grpc/metadata"
	"google.golang.org/grpc/status"
	"google.golang.org/grpc/test/bufconn"
	emptypb "google.golang.org/protobuf/types/known/emptypb"
)

func TestInvokeContract(t *testing.T) {
	lis := bufconn.Listen(1024 * 1024)
	s := grpc.NewServer()

	s.RegisterService(&grpc.ServiceDesc{
		ServiceName: "test.EchoService",
		HandlerType: (*any)(nil),
		Methods: []grpc.MethodDesc{
			{
				MethodName: "Echo",
				Handler: func(srv any, ctx context.Context, dec func(any) error, interceptor grpc.UnaryServerInterceptor) (any, error) {
					in := new(emptypb.Empty)
					if err := dec(in); err != nil {
						return nil, err
					}
					if err := grpc.SendHeader(ctx, metadata.Pairs("x-resp-header", "header-value")); err != nil {
						return nil, err
					}
					if err := grpc.SetTrailer(ctx, metadata.Pairs("x-resp-trailer", "trailer-value")); err != nil {
						return nil, err
					}
					return in, nil
				},
			},
		},
		Streams: []grpc.StreamDesc{},
	}, nil)

	go func() {
		_ = s.Serve(lis)
	}()
	defer s.Stop()

	var interceptorMethod string
	var interceptorCalled bool
	interceptor := func(ctx context.Context, method string, req, reply any, cc *grpc.ClientConn, invoker grpc.UnaryInvoker, opts ...grpc.CallOption) error {
		interceptorCalled = true
		interceptorMethod = method
		return invoker(ctx, method, req, reply, cc, opts...)
	}

	dialer := func(context.Context, string) (net.Conn, error) {
		return lis.Dial()
	}

	cc, err := grpc.NewClient("passthrough://localhost/bufnet",
		grpc.WithContextDialer(dialer),
		grpc.WithTransportCredentials(insecure.NewCredentials()),
		grpc.WithUnaryInterceptor(interceptor),
	)
	if err != nil {
		t.Fatalf("Failed to create ClientConn: %v", err)
	}
	defer cc.Close()

	t.Run("Invoke sends a unary RPC request over a ClientConn, invoking configured unary client interceptors and capturing response header and trailer metadata passed via grpc.Header and grpc.Trailer CallOptions.", func(t *testing.T) {
		ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
		defer cancel()

		req := &emptypb.Empty{}
		resp := &emptypb.Empty{}
		var headerMD, trailerMD metadata.MD

		err := grpc.Invoke(
			ctx,
			"/test.EchoService/Echo",
			req,
			resp,
			cc,
			grpc.Header(&headerMD),
			grpc.Trailer(&trailerMD),
		)
		if err != nil {
			t.Fatalf("grpc.Invoke failed: %v", err)
		}

		if !interceptorCalled {
			t.Fatalf("Expected unary interceptor to be invoked")
		}
		if interceptorMethod != "/test.EchoService/Echo" {
			t.Fatalf("Expected interceptor method /test.EchoService/Echo, got %s", interceptorMethod)
		}
		if vals := headerMD.Get("x-resp-header"); len(vals) == 0 || vals[0] != "header-value" {
			t.Fatalf("Expected header metadata x-resp-header: header-value, got %v", headerMD)
		}
		if vals := trailerMD.Get("x-resp-trailer"); len(vals) == 0 || vals[0] != "trailer-value" {
			t.Fatalf("Expected trailer metadata x-resp-trailer: trailer-value, got %v", trailerMD)
		}
	})

	t.Run("Invoke immediately returns a gRPC status error with code Canceled when invoked with an already canceled context.", func(t *testing.T) {
		ctx, cancel := context.WithCancel(context.Background())
		cancel() // immediately cancel

		req := &emptypb.Empty{}
		resp := &emptypb.Empty{}
		err := grpc.Invoke(ctx, "/test.EchoService/Echo", req, resp, cc)
		if err == nil {
			t.Fatalf("Expected error invoking with canceled context, got nil")
		}
		if st, ok := status.FromError(err); !ok || st.Code() != codes.Canceled {
			t.Fatalf("Expected codes.Canceled status, got %v (status: %v)", err, st)
		}
	})

	t.Run("Invoke returns ErrClientConnClosing when invoked on a closed ClientConn.", func(t *testing.T) {
		closedCC, err := grpc.NewClient("passthrough://localhost/bufnet",
			grpc.WithContextDialer(dialer),
			grpc.WithTransportCredentials(insecure.NewCredentials()),
		)
		if err != nil {
			t.Fatalf("Failed to create ClientConn: %v", err)
		}
		if err := closedCC.Close(); err != nil {
			t.Fatalf("Failed to close ClientConn: %v", err)
		}

		req := &emptypb.Empty{}
		resp := &emptypb.Empty{}
		err = grpc.Invoke(context.Background(), "/test.EchoService/Echo", req, resp, closedCC)
		if err == nil {
			t.Fatalf("Expected error invoking on closed ClientConn, got nil")
		}
		if !errors.Is(err, grpc.ErrClientConnClosing) && status.Code(err) != codes.Canceled {
			t.Fatalf("Expected ErrClientConnClosing or Canceled code, got: %v", err)
		}
	})
}