agones.dev/agones@v1.53.0/examples/allocator-client/main.go (about)

     1  // Copyright 2020 Google LLC All Rights Reserved.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package main
    16  
    17  import (
    18  	"context"
    19  	"crypto/tls"
    20  	"crypto/x509"
    21  	"flag"
    22  	"fmt"
    23  	"os"
    24  
    25  	pb "agones.dev/agones/pkg/allocation/go"
    26  	"github.com/pkg/errors"
    27  	"google.golang.org/grpc"
    28  	"google.golang.org/grpc/credentials"
    29  )
    30  
    31  func main() {
    32  	keyFile := flag.String("key", "missing key", "the private key file for the client certificate in PEM format")
    33  	certFile := flag.String("cert", "missing cert", "the public key file for the client certificate in PEM format")
    34  	cacertFile := flag.String("cacert", "missing cacert", "the CA cert file for server signing certificate in PEM format")
    35  	externalIP := flag.String("ip", "missing external IP", "the external IP for allocator server")
    36  	port := flag.String("port", "443", "the port for allocator server")
    37  	namespace := flag.String("namespace", "default", "the game server kubernetes namespace")
    38  	multicluster := flag.Bool("multicluster", false, "set to true to enable the multi-cluster allocation")
    39  
    40  	flag.Parse()
    41  
    42  	endpoint := *externalIP + ":" + *port
    43  	cert, err := os.ReadFile(*certFile)
    44  	if err != nil {
    45  		panic(err)
    46  	}
    47  	key, err := os.ReadFile(*keyFile)
    48  	if err != nil {
    49  		panic(err)
    50  	}
    51  	cacert, err := os.ReadFile(*cacertFile)
    52  	if err != nil {
    53  		panic(err)
    54  	}
    55  
    56  	request := &pb.AllocationRequest{
    57  		Namespace: *namespace,
    58  		MultiClusterSetting: &pb.MultiClusterSetting{
    59  			Enabled: *multicluster,
    60  		},
    61  	}
    62  
    63  	dialOpts, err := createRemoteClusterDialOption(cert, key, cacert)
    64  	if err != nil {
    65  		panic(err)
    66  	}
    67  	conn, err := grpc.NewClient(endpoint, dialOpts)
    68  	if err != nil {
    69  		panic(err)
    70  	}
    71  	defer conn.Close()
    72  
    73  	grpcClient := pb.NewAllocationServiceClient(conn)
    74  	response, err := grpcClient.Allocate(context.Background(), request)
    75  	if err != nil {
    76  		panic(err)
    77  	}
    78  	fmt.Printf("response: %s\n", response.String())
    79  }
    80  
    81  // createRemoteClusterDialOption creates a grpc client dial option with TLS configuration.
    82  func createRemoteClusterDialOption(clientCert, clientKey, caCert []byte) (grpc.DialOption, error) {
    83  	// Load client cert
    84  	cert, err := tls.X509KeyPair(clientCert, clientKey)
    85  	if err != nil {
    86  		return nil, err
    87  	}
    88  
    89  	tlsConfig := &tls.Config{Certificates: []tls.Certificate{cert}}
    90  	if len(caCert) != 0 {
    91  		// Load CA cert, if provided and trust the server certificate.
    92  		// This is required for self-signed certs.
    93  		tlsConfig.RootCAs = x509.NewCertPool()
    94  		if !tlsConfig.RootCAs.AppendCertsFromPEM(caCert) {
    95  			return nil, errors.New("only PEM format is accepted for server CA")
    96  		}
    97  	}
    98  
    99  	return grpc.WithTransportCredentials(credentials.NewTLS(tlsConfig)), nil
   100  }