|
| 1 | +package main |
| 2 | + |
| 3 | +import ( |
| 4 | + "context" |
| 5 | + "errors" |
| 6 | + "github.com/aws/aws-sdk-go-v2/aws" |
| 7 | + "github.com/aws/aws-sdk-go-v2/config" |
| 8 | + "github.com/aws/aws-sdk-go-v2/service/ecs" |
| 9 | + core "github.com/envoyproxy/go-control-plane/envoy/config/core/v3" |
| 10 | + endpoint "github.com/envoyproxy/go-control-plane/envoy/config/endpoint/v3" |
| 11 | + discovery "github.com/envoyproxy/go-control-plane/envoy/service/discovery/v3" |
| 12 | + endpointservice "github.com/envoyproxy/go-control-plane/envoy/service/endpoint/v3" |
| 13 | + "github.com/envoyproxy/go-control-plane/pkg/cache/types" |
| 14 | + "github.com/envoyproxy/go-control-plane/pkg/cache/v3" |
| 15 | + "github.com/envoyproxy/go-control-plane/pkg/resource/v3" |
| 16 | + gocache "github.com/patrickmn/go-cache" |
| 17 | + log "github.com/sirupsen/logrus" |
| 18 | + "google.golang.org/grpc" |
| 19 | + "google.golang.org/grpc/reflection" |
| 20 | + "net" |
| 21 | + "os" |
| 22 | + "strconv" |
| 23 | + "time" |
| 24 | +) |
| 25 | + |
| 26 | +type server struct { |
| 27 | + ecs *ecs.Client |
| 28 | + cache *gocache.Cache |
| 29 | +} |
| 30 | + |
| 31 | +func init() { |
| 32 | + |
| 33 | + // Log as JSON instead of the default ASCII formatter. |
| 34 | + log.SetFormatter(&log.TextFormatter{}) |
| 35 | + |
| 36 | + // Output to stdout instead of the default stderr |
| 37 | + // Can be any io.Writer, see below for File example |
| 38 | + log.SetOutput(os.Stdout) |
| 39 | + |
| 40 | + // Only log the warning severity or above. |
| 41 | + log.SetLevel(log.InfoLevel) |
| 42 | +} |
| 43 | + |
| 44 | +func (*server) receive(stream endpointservice.EndpointDiscoveryService_StreamEndpointsServer, reqChannel chan *discovery.DiscoveryRequest) { |
| 45 | + for { |
| 46 | + req, err := stream.Recv() |
| 47 | + if err != nil { |
| 48 | + log.Error("Error while receiving message from stream", err) |
| 49 | + return |
| 50 | + } |
| 51 | + |
| 52 | + select { |
| 53 | + case reqChannel <- req: |
| 54 | + case <-stream.Context().Done(): |
| 55 | + log.Error("Stream closed") |
| 56 | + return |
| 57 | + } |
| 58 | + } |
| 59 | +} |
| 60 | + |
| 61 | +func (s *server) StreamEndpoints(stream endpointservice.EndpointDiscoveryService_StreamEndpointsServer) error { |
| 62 | + stop := make(chan struct{}) |
| 63 | + reqChannel := make(chan *discovery.DiscoveryRequest, 1) |
| 64 | + go s.receive(stream, reqChannel) |
| 65 | + |
| 66 | + for { |
| 67 | + select { |
| 68 | + case req, ok := <-reqChannel: |
| 69 | + if !ok { |
| 70 | + log.Error("Error receiving request") |
| 71 | + return errors.New("Error receiving request") |
| 72 | + } |
| 73 | + eds, cacheOk := s.cache.Get(req.ResourceNames[0]) |
| 74 | + if !cacheOk { |
| 75 | + eds = s.generateEDS(req.ResourceNames[0]) |
| 76 | + s.cache.Set(req.ResourceNames[0], eds, time.Minute*1) |
| 77 | + } |
| 78 | + response := cache.RawResponse{Version: req.VersionInfo, |
| 79 | + Resources: []types.ResourceWithTtl{{Resource: eds.(*endpoint.ClusterLoadAssignment)}}, |
| 80 | + Request: &discovery.DiscoveryRequest{TypeUrl: resource.EndpointType}} |
| 81 | + cacheResp, err := response.GetDiscoveryResponse() |
| 82 | + err = stream.Send(cacheResp) |
| 83 | + if err != nil { |
| 84 | + log.Error("Error StreamingEndpoint ", err) |
| 85 | + return err |
| 86 | + } |
| 87 | + case <-stop: |
| 88 | + return nil |
| 89 | + } |
| 90 | + } |
| 91 | +} |
| 92 | + |
| 93 | +func (s *server) DeltaEndpoints(stream endpointservice.EndpointDiscoveryService_DeltaEndpointsServer) error { |
| 94 | + log.Info("DeltaEndpoints service not implemented") |
| 95 | + return nil |
| 96 | +} |
| 97 | + |
| 98 | +func (*server) FetchEndpoints(ctx context.Context, req *discovery.DiscoveryRequest) (*discovery.DiscoveryResponse, error) { |
| 99 | + log.Info("FetchEndpoints service not implemented") |
| 100 | + return nil, nil |
| 101 | +} |
| 102 | + |
| 103 | +func (s *server) generateEDS(cluster string) *endpoint.ClusterLoadAssignment { |
| 104 | + var lbEndpoints = make([]*endpoint.LbEndpoint, 0) |
| 105 | + |
| 106 | + s.getTaskIps(&lbEndpoints, cluster, nil) |
| 107 | + |
| 108 | + ret := &endpoint.ClusterLoadAssignment{ |
| 109 | + ClusterName: cluster, |
| 110 | + Endpoints: []*endpoint.LocalityLbEndpoints{ |
| 111 | + { |
| 112 | + LbEndpoints: lbEndpoints, |
| 113 | + }, |
| 114 | + }, |
| 115 | + } |
| 116 | + |
| 117 | + return ret |
| 118 | +} |
| 119 | + |
| 120 | +func (s *server) getTaskIps(lbEndpoints *[]*endpoint.LbEndpoint, cluster string, nextToken *string) { |
| 121 | + taskArns, err := s.ecs.ListTasks(context.Background(), &ecs.ListTasksInput{Cluster: aws.String(cluster), NextToken: nextToken}) |
| 122 | + if err != nil { |
| 123 | + log.Error("Error listing AWS tasks ", err) |
| 124 | + return |
| 125 | + } |
| 126 | + tasks, err := s.ecs.DescribeTasks(context.Background(), &ecs.DescribeTasksInput{ |
| 127 | + Tasks: taskArns.TaskArns, Cluster: aws.String(cluster), |
| 128 | + }) |
| 129 | + if err != nil { |
| 130 | + log.Error("Error Describing AWS tasks ", err) |
| 131 | + return |
| 132 | + } |
| 133 | + port, err := strconv.Atoi(os.Getenv(cluster + "_port")) |
| 134 | + if err != nil { |
| 135 | + port = 80 |
| 136 | + } |
| 137 | + for _, task := range tasks.Tasks { |
| 138 | + for _, attachment := range task.Attachments { |
| 139 | + for _, details := range attachment.Details { |
| 140 | + if aws.ToString(details.Name) == "privateIPv4Address" { |
| 141 | + *lbEndpoints = append(*lbEndpoints, &endpoint.LbEndpoint{HostIdentifier: &endpoint.LbEndpoint_Endpoint{ |
| 142 | + Endpoint: &endpoint.Endpoint{ |
| 143 | + Address: &core.Address{ |
| 144 | + Address: &core.Address_SocketAddress{ |
| 145 | + SocketAddress: &core.SocketAddress{ |
| 146 | + Address: aws.ToString(details.Value), |
| 147 | + PortSpecifier: &core.SocketAddress_PortValue{ |
| 148 | + PortValue: uint32(port), |
| 149 | + }, |
| 150 | + }, |
| 151 | + }, |
| 152 | + }, |
| 153 | + }, |
| 154 | + }, |
| 155 | + }) |
| 156 | + } |
| 157 | + } |
| 158 | + } |
| 159 | + } |
| 160 | + if taskArns.NextToken != nil { |
| 161 | + s.getTaskIps(lbEndpoints, cluster, taskArns.NextToken) |
| 162 | + } |
| 163 | +} |
| 164 | +func main() { |
| 165 | + grpcServer := grpc.NewServer() |
| 166 | + edsListen := os.Getenv("EDS_LISTEN") |
| 167 | + if edsListen == "" { |
| 168 | + edsListen = "0.0.0.0:5678" |
| 169 | + } |
| 170 | + lis, err := net.Listen("tcp", edsListen) |
| 171 | + if err != nil { |
| 172 | + log.Error(err) |
| 173 | + } |
| 174 | + |
| 175 | + cfg, _ := config.LoadDefaultConfig(context.Background()) |
| 176 | + endpointservice.RegisterEndpointDiscoveryServiceServer(grpcServer, &server{ecs: ecs.NewFromConfig(cfg), cache: gocache.New(time.Minute*1, time.Minute*1)}) |
| 177 | + |
| 178 | + reflection.Register(grpcServer) |
| 179 | + |
| 180 | + log.Infof("management server listening on %d", 5678) |
| 181 | + if err = grpcServer.Serve(lis); err != nil { |
| 182 | + log.Error(err) |
| 183 | + } |
| 184 | +} |
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