Add message queue agent (#6463)

* scaffold message queue agent

* adjust proto, add mq_agent

* add agent client implementation

* remove unused function

* agent publish server implementation

* adding agent

weed/command/mq_agent.go

@@ -0,0 +1,74 @@
+package command
+
+import (
+	"github.com/seaweedfs/seaweedfs/weed/mq/agent"
+	"github.com/seaweedfs/seaweedfs/weed/pb/mq_agent_pb"
+	"google.golang.org/grpc/reflection"
+
+	"github.com/seaweedfs/seaweedfs/weed/glog"
+	"github.com/seaweedfs/seaweedfs/weed/pb"
+	"github.com/seaweedfs/seaweedfs/weed/security"
+	"github.com/seaweedfs/seaweedfs/weed/util"
+)
+
+var (
+	mqAgentOptions MessageQueueAgentOptions
+)
+
+type MessageQueueAgentOptions struct {
+	brokers       []pb.ServerAddress
+	brokersString *string
+	filerGroup    *string
+	ip            *string
+	port          *int
+}
+
+func init() {
+	cmdMqAgent.Run = runMqAgent // break init cycle
+	mqAgentOptions.brokersString = cmdMqAgent.Flag.String("broker", "localhost:17777", "comma-separated message queue brokers")
+	mqAgentOptions.ip = cmdMqAgent.Flag.String("ip", "localhost", "message queue agent host address")
+	mqAgentOptions.port = cmdMqAgent.Flag.Int("port", 16777, "message queue agent gRPC server port")
+}
+
+var cmdMqAgent = &Command{
+	UsageLine: "mq.agent [-port=6377] [-master=<ip:port>]",
+	Short:     "<WIP> start a message queue agent",
+	Long: `start a message queue agent
+
+	The agent runs on local server to accept gRPC calls to write or read messages. 
+	The messages are sent to message queue brokers.
+
+`,
+}
+
+func runMqAgent(cmd *Command, args []string) bool {
+
+	util.LoadSecurityConfiguration()
+
+	mqAgentOptions.brokers = pb.ServerAddresses(*mqAgentOptions.brokersString).ToAddresses()
+
+	return mqAgentOptions.startQueueAgent()
+
+}
+
+func (mqAgentOpt *MessageQueueAgentOptions) startQueueAgent() bool {
+
+	grpcDialOption := security.LoadClientTLS(util.GetViper(), "grpc.msg_agent")
+
+	agentServer := agent.NewMessageQueueAgent(&agent.MessageQueueAgentOptions{
+		SeedBrokers: mqAgentOpt.brokers,
+	}, grpcDialOption)
+
+	// start grpc listener
+	grpcL, _, err := util.NewIpAndLocalListeners(*mqAgentOpt.ip, *mqAgentOpt.port, 0)
+	if err != nil {
+		glog.Fatalf("failed to listen on grpc port %d: %v", *mqAgentOpt.port, err)
+	}
+	grpcS := pb.NewGrpcServer()
+	mq_agent_pb.RegisterSeaweedMessagingAgentServer(grpcS, agentServer)
+	reflection.Register(grpcS)
+	grpcS.Serve(grpcL)
+
+	return true
+
+}

weed/command/scaffold/security.toml

@@ -89,6 +89,11 @@ cert = ""
 key = ""
 allowed_commonNames = ""    # comma-separated SSL certificate common names
 
+[grpc.msg_agent]
+cert = ""
+key = ""
+allowed_commonNames = ""    # comma-separated SSL certificate common names
+
 # use this for any place needs a grpc client
 # i.e., "weed backup|benchmark|filer.copy|filer.replicate|mount|s3|upload"
 [grpc.client]