feat: handle logging from the agent

app/server/hp-agent.ts

@@ -1,8 +1,8 @@
 import { ChildProcessWithoutNullStreams, spawn } from 'node:child_process';
 import EventEmitter from 'node:events';
-import { constants, access, mkdir, open } from 'node:fs/promises';
+import { access, constants, mkdir, open } from 'node:fs/promises';
 import { getegid, geteuid } from 'node:process';
-import { Interface, createInterface } from 'node:readline';
+import { createInterface, Interface } from 'node:readline';
 import { inArray } from 'drizzle-orm';
 import { LibSQLDatabase } from 'drizzle-orm/libsql/driver-core';
 import { HostInfo } from '~/types';
@@ -240,7 +240,6 @@ class HeadplaneAgent extends EventEmitter<AgentEvents> {
 			gid: getegid?.() ?? undefined,
 			env: {
 				HOME: process.env.HOME,
-				HEADPLANE_EMBEDDED: 'true',
 				HEADPLANE_AGENT_WORK_DIR: this.options.work_dir,
 				HEADPLANE_AGENT_DEBUG: log.debugEnabled ? 'true' : 'false',
 				HEADPLANE_AGENT_HOSTNAME: this.options.host_name,
@@ -396,5 +395,26 @@ class HeadplaneAgent extends EventEmitter<AgentEvents> {
 			this.emit('error', new Error(error));
 			return;
 		}
+
+		if (line.startsWith('LOG')) {
+			const logSnippet = line.slice(4).trim();
+			const [level, ...messageParts] = logSnippet.split(' ');
+			const message = messageParts.join(' ');
+			switch (level) {
+				case 'INFO':
+					log.info('agent', message);
+					break;
+				case 'WARN':
+					log.warn('agent', message);
+					break;
+				case 'ERROR':
+					log.error('agent', message);
+					break;
+				default:
+					log.debug('agent', message);
+			}
+
+			return;
+		}
 	}
 }

cmd/hp_agent/hp_agent.go

@@ -1,11 +1,13 @@
 package main
 
 import (
+	"bufio"
+	"context"
 	"fmt"
+	"os"
+	"strings"
 
-	_ "github.com/joho/godotenv/autoload"
 	"github.com/tale/headplane/internal/config"
-	"github.com/tale/headplane/internal/hpagent"
 	"github.com/tale/headplane/internal/tsnet"
 	"github.com/tale/headplane/internal/util"
 )
@@ -24,15 +26,36 @@ func main() {
 
 	log.SetDebug(cfg.Debug)
 	agent := tsnet.NewAgent(cfg)
-
-	agent.Connect()
 	defer agent.Shutdown()
 
-	log.Msg(&Register{
+	scanner := bufio.NewScanner(os.Stdin)
-		Type: "register",
+	for scanner.Scan() {
-		ID:   agent.ID,
+		line := scanner.Bytes()
-	})
+		directive := strings.TrimSpace(string(line))
+		log.Debug("Received directive: %s", directive)
 
-	fmt.Println("READY")
+		switch directive {
-	hpagent.FollowMaster(agent)
+		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)
+			}
+		}
+	}
+
+	if err := scanner.Err(); err != nil {
+		fmt.Printf("ERROR %s\n", err)
+		os.Exit(1)
+	}
 }

go.mod

@@ -3,7 +3,6 @@ module github.com/tale/headplane
 go 1.24.4
 
 require (
-	github.com/joho/godotenv v1.5.1
 	go4.org/mem v0.0.0-20240501181205-ae6ca9944745
 	golang.org/x/crypto v0.41.0
 	tailscale.com v1.86.4

go.sum

@@ -99,8 +99,6 @@ github.com/jmespath/go-jmespath v0.4.0 h1:BEgLn5cpjn8UN1mAw4NjwDrS35OdebyEtFe+9Y
 github.com/jmespath/go-jmespath v0.4.0/go.mod h1:T8mJZnbsbmF+m6zOOFylbeCJqk5+pHWvzYPziyZiYoo=
 github.com/jmespath/go-jmespath/internal/testify v1.5.1 h1:shLQSRRSCCPj3f2gpwzGwWFoC7ycTf1rcQZHOlsJ6N8=
 github.com/jmespath/go-jmespath/internal/testify v1.5.1/go.mod h1:L3OGu8Wl2/fWfCI6z80xFu9LTZmf1ZRjMHUOPmWr69U=
-github.com/joho/godotenv v1.5.1 h1:7eLL/+HRGLY0ldzfGMeQkb7vMd0as4CfYvUVzLqw0N0=
-github.com/joho/godotenv v1.5.1/go.mod h1:f4LDr5Voq0i2e/R5DDNOoa2zzDfwtkZa6DnEwAbqwq4=
 github.com/jsimonetti/rtnetlink v1.4.0 h1:Z1BF0fRgcETPEa0Kt0MRk3yV5+kF1FWTni6KUFKrq2I=
 github.com/jsimonetti/rtnetlink v1.4.0/go.mod h1:5W1jDvWdnthFJ7fxYX1GMK07BUpI4oskfOqvPteYS6E=
 github.com/klauspost/compress v1.17.11 h1:In6xLpyWOi1+C7tXUUWv2ot1QvBjxevKAaI6IXrJmUc=

internal/config.go

@@ -1,45 +0,0 @@
-package config
-
-import "os"
-
-// Config represents the configuration for the agent.
-type Config struct {
-	Debug        bool
-	Hostname     string
-	TSControlURL string
-	TSAuthKey    string
-	WorkDir      string
-}
-
-const (
-	DebugEnv        = "HEADPLANE_AGENT_DEBUG"
-	HostnameEnv     = "HEADPLANE_AGENT_HOSTNAME"
-	TSControlURLEnv = "HEADPLANE_AGENT_TS_SERVER"
-	TSAuthKeyEnv    = "HEADPLANE_AGENT_TS_AUTHKEY"
-	WorkDirEnv      = "HEADPLANE_AGENT_WORK_DIR"
-)
-
-// Load reads the agent configuration from environment variables.
-func Load() (*Config, error) {
-	c := &Config{
-		Debug:        false,
-		Hostname:     os.Getenv(HostnameEnv),
-		TSControlURL: os.Getenv(TSControlURLEnv),
-		TSAuthKey:    os.Getenv(TSAuthKeyEnv),
-		WorkDir:      os.Getenv(WorkDirEnv),
-	}
-
-	if os.Getenv(DebugEnv) == "true" {
-		c.Debug = true
-	}
-
-	if err := validateRequired(c); err != nil {
-		return nil, err
-	}
-
-	if err := validateTSReady(c); err != nil {
-		return nil, err
-	}
-
-	return c, nil
-}

internal/hpagent/handler.go

@@ -1,55 +0,0 @@
-package hpagent
-
-import (
-	"bufio"
-	"context"
-	"fmt"
-
-	"os"
-
-	"github.com/tale/headplane/internal/tsnet"
-	"github.com/tale/headplane/internal/util"
-)
-
-// Starts listening for messages from stdin
-func FollowMaster(agent *tsnet.TSAgent) {
-	log := util.GetLogger()
-	scanner := bufio.NewScanner(os.Stdin)
-	log.Info("Listening for messages from Headplane master on stdin")
-
-	for scanner.Scan() {
-		line := scanner.Bytes()
-		directive := string(line)
-
-		log.Debug("Received directive from master: %s", directive)
-		switch directive {
-		case "SHUTDOWN":
-			log.Debug("Received SHUTDOWN directive from master, shutting down agent")
-			agent.Shutdown()
-			return
-
-		case "START":
-			log.Debug("Received START directive from master, starting agent")
-			// TODO: Start the agent here instead of in main
-			fmt.Println("READY " + agent.ID)
-			continue
-
-		case "PING":
-			log.Debug("Received PING directive from master, responding with PONG")
-			fmt.Println("PONG " + agent.ID)
-			continue
-
-		case "REFRESH":
-			log.Debug("Received REFRESH directive from master, refreshing status for all nodes")
-			err := agent.DispatchHostInfo(context.Background())
-			if err != nil {
-				log.Error("Error refreshing host info: %s", err)
-				fmt.Println("ERR " + err.Error())
-			}
-		}
-	}
-
-	if err := scanner.Err(); err != nil {
-		log.Fatal("Error reading from stdin: %s", err)
-	}
-}

internal/preflight.go

@@ -1,48 +0,0 @@
-package config
-
-import (
-	"fmt"
-	"net/http"
-	"strings"
-)
-
-// Checks to make sure all required environment variables are set
-func validateRequired(config *Config) error {
-	if config.Hostname == "" {
-		return fmt.Errorf("%s is required", HostnameEnv)
-	}
-
-	if config.TSControlURL == "" {
-		return fmt.Errorf("%s is required", TSControlURLEnv)
-	}
-
-	if config.TSAuthKey == "" {
-		return fmt.Errorf("%s is required", TSAuthKeyEnv)
-	}
-
-	if config.WorkDir == "" {
-		return fmt.Errorf("%s is required", WorkDirEnv)
-	}
-
-	return nil
-}
-
-// Pings the Tailscale control server to make sure it's up and running
-func validateTSReady(config *Config) error {
-	testURL := config.TSControlURL
-	if strings.HasSuffix(testURL, "/") {
-		testURL = testURL[:len(testURL)-1]
-	}
-
-	testURL = fmt.Sprintf("%s/health", testURL)
-	resp, err := http.Get(testURL)
-	if err != nil {
-		return fmt.Errorf("Failed to connect to TS control server: %s", err)
-	}
-
-	if resp.StatusCode != 200 {
-		return fmt.Errorf("Failed to connect to TS control server: %s", resp.Status)
-	}
-
-	return nil
-}

internal/util/logger.go

@@ -4,19 +4,16 @@ import (
 	"encoding/json"
 	"fmt"
 	"os"
-	"strings"
 	"sync"
-	"time"
 )
 
 type LogLevel string
 
 const (
-	LevelInfo  LogLevel = "info"
+	LevelInfo  LogLevel = "INFO"
-	LevelDebug LogLevel = "debug"
+	LevelDebug LogLevel = "DEBUG"
-	LevelError LogLevel = "error"
+	LevelError LogLevel = "ERROR"
-	LevelFatal LogLevel = "fatal"
+	LevelFatal LogLevel = "FATAL"
-	LevelMsg   LogLevel = "msg"
 )
 
 type LogMessage struct {
@@ -61,19 +58,8 @@ func (l *Logger) SetDebug(enabled bool) {
 
 func (l *Logger) log(level LogLevel, format string, v ...any) {
 	msg := fmt.Sprintf(format, v...)
-	timestamp := time.Now().Format(time.RFC3339)
 
-	// Manually construct compact JSON line for performance
+	fmt.Printf("LOG %s %s\n", level, msg)
-	line := `{"Level":"` + string(level) +
-		`","Time":"` + timestamp +
-		`","Message":"` + escapeString(msg) + `"}` + "\n"
-
-	if level == LevelError || level == LevelFatal {
-		os.Stderr.WriteString(line)
-	}
-
-	// Always write to stdout but also write to stderr for errors
-	os.Stdout.WriteString(line)
 	if level == LevelFatal {
 		os.Exit(1)
 	}
@@ -88,53 +74,3 @@ func (l *Logger) Debug(format string, v ...any) {
 func (l *Logger) Info(format string, v ...any)  { l.log(LevelInfo, format, v...) }
 func (l *Logger) Error(format string, v ...any) { l.log(LevelError, format, v...) }
 func (l *Logger) Fatal(format string, v ...any) { l.log(LevelFatal, format, v...) }
-
-func (l *Logger) Msg(obj any) {
-	entry := l.pool.Get().(*LogMessage)
-	defer l.pool.Put(entry)
-
-	entry.Level = LevelMsg
-	entry.Time = time.Now().Format(time.RFC3339)
-	entry.Message = obj
-
-	// Because the encoder is tied to STDOUT we get a message
-	_ = l.encoder.Encode(entry)
-
-	// Reset the entry for reuse
-	entry.Level = ""
-	entry.Time = ""
-	entry.Message = nil
-}
-
-func escapeString(s string) string {
-	var b strings.Builder
-	b.Grow(len(s) + 16) // pre-grow to reduce reallocs
-
-	for i := 0; i < len(s); i++ {
-		c := s[i]
-		switch c {
-		case '"':
-			b.WriteString(`\"`)
-		case '\\':
-			b.WriteString(`\\`)
-		case '\b':
-			b.WriteString(`\b`)
-		case '\f':
-			b.WriteString(`\f`)
-		case '\n':
-			b.WriteString(`\n`)
-		case '\r':
-			b.WriteString(`\r`)
-		case '\t':
-			b.WriteString(`\t`)
-		default:
-			if c < 0x20 {
-				// Control characters like 0x01, 0x07 (bell), etc.
-				fmt.Fprintf(&b, `\u%04x`, c)
-			} else {
-				b.WriteByte(c)
-			}
-		}
-	}
-	return b.String()
-}

nix/agent.nix

@@ -3,7 +3,7 @@ buildGoModule {
   pname = "hp_agent";
   version = (builtins.fromJSON (builtins.readFile ../package.json)).version;
   src = ../.;
-  vendorHash = "sha256-AyJx1os4auTmHvz+KLY+RGyysa3LWi8r2+QLxofPUH4=";
+  vendorHash = "sha256-cPE8cnfTdzi6hAmSXujKmfd5ezivc3sQ6DKOZubCpYI=";
   ldflags = ["-s" "-w"];
   env.CGO_ENABLED = 0;
 }

nix/ssh-wasm.nix

@@ -14,7 +14,7 @@ in
     version = (builtins.fromJSON (builtins.readFile ../package.json)).version;
     src = ../.;
     subPackages = ["cmd/hp_ssh"];
-    vendorHash = "sha256-AyJx1os4auTmHvz+KLY+RGyysa3LWi8r2+QLxofPUH4=";
+    vendorHash = "sha256-cPE8cnfTdzi6hAmSXujKmfd5ezivc3sQ6DKOZubCpYI=";
     env.CGO_ENABLED = 0;
 
     nativeBuildInputs = [go];