feat: switch agent to a periodic dump rather than long running process

cmd/hp_agent/hp_agent.go

@@ -1,22 +1,15 @@
 package main
 
 import (
-	"bufio"
 	"context"
-	"fmt"
+	"encoding/json"
 	"os"
-	"strings"
 
 	"github.com/tale/headplane/internal/config"
 	"github.com/tale/headplane/internal/tsnet"
 	"github.com/tale/headplane/internal/util"
 )
 
-type Register struct {
-	Type string
-	ID   string
-}
-
 func main() {
 	log := util.GetLogger()
 	cfg, err := config.Load()
@@ -28,34 +21,23 @@ func main() {
 	agent := tsnet.NewAgent(cfg)
 	defer agent.Shutdown()
 
-	scanner := bufio.NewScanner(os.Stdin)
-	for scanner.Scan() {
-		line := scanner.Bytes()
-		directive := strings.TrimSpace(string(line))
-		log.Debug("Received directive: %s", directive)
+	agent.Connect()
 
-		switch directive {
-		case "START":
-			agent.Connect()
-			fmt.Printf("READY %s\n", agent.ID)
-
-		case "SHUTDOWN":
-			agent.Shutdown()
-			os.Exit(0)
-
-		case "PING":
-			fmt.Printf("PONG %s\n", agent.ID)
-
-		case "REFRESH":
-			err := agent.DispatchHostInfo(context.Background())
-			if err != nil {
-				fmt.Printf("ERROR %s\n", err)
-			}
-		}
+	hosts, err := agent.FetchAllHostInfo(context.Background())
+	if err != nil {
+		log.Fatal("Failed to fetch host info: %s", err)
 	}
 
-	if err := scanner.Err(); err != nil {
-		fmt.Printf("ERROR %s\n", err)
-		os.Exit(1)
+	output := struct {
+		Self  string                     `json:"self"`
+		Hosts map[string]json.RawMessage `json:"hosts"`
+	}{
+		Self:  agent.ID,
+		Hosts: hosts,
+	}
+
+	enc := json.NewEncoder(os.Stdout)
+	if err := enc.Encode(output); err != nil {
+		log.Fatal("Failed to encode result: %s", err)
 	}
 }