Refactor to use new config style

cmd/launcher/main.go

@@ -40,19 +40,18 @@ func main() {
 	errorreporting.Init(cfg.Sentry)
 	defer errorreporting.Close()
 
-	srv := http.NewHealthCheckServer()
+	srv := http.NewHealthCheckServer(cfg.HealthCheckServerPort)
 	go func() {
-		logs.Infof("Starting health check server at port %d", http.GetPort())
-
 		if err := srv.ListenAndServe(); err != nil {
 			errMsg := "Health check server failed to start"
 			if opErr, ok := err.(*net.OpError); ok && opErr.Op == "listen" {
-				errMsg = fmt.Sprintf("%s: Port %d is already in use", errMsg, http.GetPort())
+				errMsg = fmt.Sprintf("%s: Port %s is already in use", errMsg, srv.Addr)
 			} else {
 				errMsg = fmt.Sprintf("%s: %s", errMsg, err)
 			}
 			logs.Error(errMsg)
 		}
+		logs.Infof("Started launcher's health check server at port %d", srv.Addr)
 	}()
 
 	cmd := &commands.LaunchCommand{}

internal/config/config.go

@@ -17,6 +17,11 @@ var configPath = "/etc/n8n-task-runners.json"
 
 var cfg Config
 
+const (
+	// EnvVarHealthCheckPort is the env var for the port for the launcher's health check server.
+	EnvVarHealthCheckPort = "N8N_LAUNCHER_HEALTCHECK_PORT"
+)
+
 // Config holds the full configuration for the launcher.
 type Config struct {
 	// LogLevel is the log level for the launcher. Default: `info`.
@@ -33,6 +38,9 @@ type Config struct {
 	// TaskBrokerURI is the URI of the task broker server.
 	TaskBrokerURI string `env:"N8N_TASK_BROKER_URI, default=http://127.0.0.1:5679"`
 
+	// HealthCheckServerPort is the port for the launcher's health check server.
+	HealthCheckServerPort string `env:"N8N_LAUNCHER_HEALTCHECK_PORT, default=5680"`
+
 	// Runner is the runner config for the task runner, obtained from:
 	// `/etc/n8n-task-runners.json`.
 	Runner *RunnerConfig
@@ -92,6 +100,10 @@ func LoadConfig(runnerType string, lookuper envconfig.Lookuper) (*Config, error)
 		cfgErrs = append(cfgErrs, errs.ErrNegativeAutoShutdownTimeout)
 	}
 
+	if port, err := strconv.Atoi(cfg.HealthCheckServerPort); err != nil || port <= 0 || port >= 65536 {
+		cfgErrs = append(cfgErrs, fmt.Errorf("%s must be a valid port number", EnvVarHealthCheckPort))
+	}
+
 	// runner
 
 	runnerCfg, err := readFileConfig(runnerType)

internal/http/healthcheck_server.go

@@ -4,26 +4,22 @@ import (
 	"encoding/json"
 	"fmt"
 	"net/http"
-	"os"
-	"strconv"
 	"task-runner-launcher/internal/logs"
 	"time"
 )
 
 const (
-	defaultPort     = 5680
-	portEnvVar      = "N8N_LAUNCHER_HEALTCHECK_PORT"
 	healthCheckPath = "/healthz"
 	readTimeout     = 1 * time.Second
 	writeTimeout    = 1 * time.Second
 )
 
-func NewHealthCheckServer() *http.Server {
+func NewHealthCheckServer(port string) *http.Server {
 	mux := http.NewServeMux()
 	mux.HandleFunc(healthCheckPath, handleHealthCheck)
 
 	return &http.Server{
-		Addr:         fmt.Sprintf(":%d", GetPort()),
+		Addr:         fmt.Sprintf(":%s", port),
 		Handler:      mux,
 		ReadTimeout:  readTimeout,
 		WriteTimeout: writeTimeout,
@@ -48,14 +44,3 @@ func handleHealthCheck(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 }
-
-func GetPort() int {
-	if customPortStr := os.Getenv(portEnvVar); customPortStr != "" {
-		if customPort, err := strconv.Atoi(customPortStr); err == nil && customPort > 0 && customPort < 65536 {
-			return customPort
-		}
-		logs.Warnf("%s sets an invalid port, falling back to default port %d", portEnvVar, defaultPort)
-	}
-
-	return defaultPort
-}

internal/http/healthcheck_server_test.go

@@ -5,7 +5,6 @@ import (
 	"fmt"
 	"net/http"
 	"net/http/httptest"
-	"os"
 	"testing"
 )
 
@@ -94,7 +93,7 @@ func (w *failingWriter) WriteHeader(statusCode int) {
 }
 
 func TestNewHealthCheckServer(t *testing.T) {
-	server := NewHealthCheckServer()
+	server := NewHealthCheckServer("5680")
 
 	if server == nil {
 		t.Fatal("NewHealthCheckServer() returned nil")
@@ -113,54 +112,3 @@ func TestNewHealthCheckServer(t *testing.T) {
 		t.Errorf("NewHealthCheckServer() writeTimeout = %v, want %v", server.WriteTimeout, writeTimeout)
 	}
 }
-
-func TestGetPort(t *testing.T) {
-	tests := []struct {
-		name         string
-		envPort      string
-		expectedPort int
-	}{
-		{
-			name:         "returns default port when env var is not set",
-			envPort:      "",
-			expectedPort: defaultPort,
-		},
-		{
-			name:         "returns custom port when valid env var is set",
-			envPort:      "8080",
-			expectedPort: 8080,
-		},
-		{
-			name:         "returns default port when env var is negative",
-			envPort:      "-1",
-			expectedPort: defaultPort,
-		},
-		{
-			name:         "returns default port when env var is zero",
-			envPort:      "0",
-			expectedPort: defaultPort,
-		},
-		{
-			name:         "returns default port when env var is too large",
-			envPort:      "65536",
-			expectedPort: defaultPort,
-		},
-		{
-			name:         "returns default port when env var is not a number",
-			envPort:      "invalid",
-			expectedPort: defaultPort,
-		},
-	}
-
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			os.Setenv(portEnvVar, tt.envPort)
-
-			if got := GetPort(); got != tt.expectedPort {
-				t.Errorf("GetPort() = %v, want %v", got, tt.expectedPort)
-			}
-
-			os.Unsetenv(portEnvVar)
-		})
-	}
-}