From 000258631b76f68429560d27ee5e894b8ecc20c9 Mon Sep 17 00:00:00 2001
From: zack olson <zack@kolide.co>
Date: Fri, 16 Aug 2024 14:34:43 -0400
Subject: [PATCH] only write out identifier to flags file if non-default

---
 pkg/launcher/options.go      | 4 ++--
 pkg/launcher/options_test.go | 2 +-
 pkg/packaging/packaging.go   | 9 ++++++++-
 3 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/pkg/launcher/options.go b/pkg/launcher/options.go
index 7d2b71e00..3b5b7f3ce 100644
--- a/pkg/launcher/options.go
+++ b/pkg/launcher/options.go
@@ -17,7 +17,7 @@ import (
 	"github.com/peterbourgon/ff/v3"
 )
 
-const defaultLauncherIdentifier string = "kolide-k2"
+const DefaultLauncherIdentifier string = "kolide-k2"
 
 // Options is the set of options that may be configured for Launcher.
 type Options struct {
@@ -259,7 +259,7 @@ func ParseOptions(subcommandName string, args []string) (*Options, error) {
 		flIAmBreakingEELicense = flagset.Bool("i-am-breaking-ee-license", false, "Skip license check before running localserver (default: false)")
 		flDelayStart           = flagset.Duration("delay_start", 0*time.Second, "How much time to wait before starting launcher")
 		flLocalDevelopmentPath = flagset.String("localdev_path", "", "Path to local launcher build")
-		flPackageIdentifier    = flagset.String("identifier", defaultLauncherIdentifier, "packaging identifier used to determine service names, paths, etc. (default: kolide-k2)")
+		flPackageIdentifier    = flagset.String("identifier", DefaultLauncherIdentifier, "packaging identifier used to determine service names, paths, etc. (default: kolide-k2)")
 
 		// deprecated options, kept for any kind of config file compatibility
 		_ = flagset.String("debug_log_file", "", "DEPRECATED")
diff --git a/pkg/launcher/options_test.go b/pkg/launcher/options_test.go
index c8dadf3bf..3146f6c81 100644
--- a/pkg/launcher/options_test.go
+++ b/pkg/launcher/options_test.go
@@ -265,7 +265,7 @@ func getArgsAndResponse() (map[string]string, *Options) {
 		WatchdogDelaySec:                120,
 		WatchdogMemoryLimitMB:           600,
 		WatchdogUtilizationLimitPercent: 50,
-		Identifier:                      defaultLauncherIdentifier,
+		Identifier:                      DefaultLauncherIdentifier,
 	}
 
 	return args, opts
diff --git a/pkg/packaging/packaging.go b/pkg/packaging/packaging.go
index c10f55dd5..8a1027370 100644
--- a/pkg/packaging/packaging.go
+++ b/pkg/packaging/packaging.go
@@ -16,6 +16,7 @@ import (
 	"text/template"
 
 	"github.com/kolide/kit/fsutil"
+	"github.com/kolide/launcher/pkg/launcher"
 	"github.com/kolide/launcher/pkg/packagekit"
 
 	"go.opencensus.io/trace"
@@ -124,7 +125,13 @@ func (p *PackageOptions) Build(ctx context.Context, packageWriter io.Writer, tar
 		"root_directory":     p.canonicalizeRootDir(p.rootDir),
 		"osqueryd_path":      p.canonicalizePath(filepath.Join(p.binDir, "osqueryd")),
 		"enroll_secret_path": p.canonicalizePath(filepath.Join(p.confDir, "secret")),
-		"identifier":         p.Identifier,
+	}
+
+	// to avoid writing additional flags without a real need (newly introduced flags
+	// can cause issues with rolling back), we only set the identifier in the flags file
+	// if it is not the default value
+	if p.Identifier != launcher.DefaultLauncherIdentifier {
+		launcherMapFlags["identifier"] = p.Identifier
 	}
 
 	launcherBoolFlags := []string{}