You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: main_test.go
    path of file: ./repos/istio/samples/extauthz/cmd/extauthz
    
    the code of the file until where you have to start completion: // Copyright Istio Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package main

import (
	"context"
	"fmt"
	"net/http"
	"testing"

	authv2 "github.com/envoyproxy/go-control-plane/envoy/service/auth/v2"
	authv3 "github.com/envoyproxy/go-control-plane/envoy/service/auth/v3"
	"google.golang.org/grpc"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/credentials/insecure"
)

func TestExtAuthz(t *testing.T) {
	server := NewExtAuthzServer()
	// Start the test server on random port.
	go server.run("localhost:0", "localhost:0")

	// Prepare the HTTP request.
	httpClient := &http.Client{}
	httpReq, err := http.NewRequest(http.MethodGet, fmt.Sprintf("http://localhost:%d/check", <-server.httpPort), nil)
	if err != nil {
		t.Fatalf(err.Error())
	}

	// Prepare the gRPC request.
	conn, err := grpc.Dial(fmt.Sprintf("localhost:%d", <-server.grpcPort), grpc.WithTransportCredentials(insecure.NewCredentials()))
	if err != nil 
    
func TestExtAuthz(t *testing.T) {
	server := NewExtAuthzServer()
	// Start the test server on random port.
	go server.run("localhost:0", "localhost:0")

	// Prepare the HTTP request.
	httpClient := &http.Client{}
	httpReq, err := http.NewRequest(http.MethodGet, fmt.Sprintf("http://localhost:%d/check", <-server.httpPort), nil)
	if err != nil {
		t.Fatalf(err.Error())
	}

	// Prepare the gRPC request.
	conn, err := grpc.Dial(fmt.Sprintf("localhost:%d", <-server.grpcPort), grpc.WithTransportCredentials(insecure.NewCredentials()))
	if err != nil {
		t.Fatalf(err.Error())
	}
	defer func() { _ = conn.Close() }()
	grpcV3Client := authv3.NewAuthorizationClient(conn)
	grpcV2Client := authv2.NewAuthorizationClient(conn)

	cases := []struct {
		name     string
		isGRPCV3 bool
		isGRPCV2 bool
		header   string
		want     int
	}{
		{
			name:   "HTTP-allow",
			header: "allow",
			want:   http.StatusOK,
		},
		{
			name:   "HTTP-deny",
			header: "deny",
			want:   http.StatusForbidden,
		},
		{
			name:     "GRPCv3-allow",
			isGRPCV3: true,
			header:   "allow",
			want:     int(codes.OK),
		},
		{
			name:     "GRPCv3-deny",
			isGRPCV3: true,
			header:   "deny",
			want:     int(codes.PermissionDenied),
		},
		{
			name:     "GRPCv2-allow",
			isGRPCV2: true,
			header:   "allow",
			want:     int(codes.OK),
		},
		{
			name:     "GRPCv2-deny",
			isGRPCV2: true,
			header:   "deny",
			want:     int(codes.PermissionDenied),
		},
	}
	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			var got int
			if tc.isGRPCV3 {
				resp, err := grpcV3Client.Check(context.Background(), &authv3.CheckRequest{
					Attributes: &authv3.AttributeContext{
						Request: &authv3.AttributeContext_Request{
							Http: &authv3.AttributeContext_HttpRequest{
								Host:    "localhost",
								Path:    "/check",
								Headers: map[string]string{checkHeader: tc.header},
							},
						},
					},
				})
				if err != nil {
					t.Errorf(err.Error())
				} else {
					got = int(resp.Status.Code)
				}
			} else if tc.isGRPCV2 {
				resp, err := grpcV2Client.Check(context.Background(), &authv2.CheckRequest{
					Attributes: &authv2.AttributeContext{
						Request: &authv2.AttributeContext_Request{
							Http: &authv2.AttributeContext_HttpRequest{
								Host:    "localhost",
								Path:    "/check",
								Headers: map[string]string{checkHeader: tc.header},
							},
						},
					},
				})
				if err != nil {
					t.Errorf(err.Error())
				} else {
					got = int(resp.Status.Code)
				}
			} else {
				httpReq.Header.Set(checkHeader, tc.header)
				resp, err := httpClient.Do(httpReq)
				if err != nil {
					t.Errorf(err.Error())
				} else {
					got = resp.StatusCode
					resp.Body.Close()
				}
			}
			if got != tc.want {
				t.Errorf("want %d but got %d", tc.want, got)
			}
		})
	}
}