Migrate legacy server units in systemd install

Author: lawrencecchen

README.md

@@ -80,6 +80,8 @@ This creates a `subrouter` system user, stores state under `/var/lib/subrouter`,
 /usr/local/bin/subrouter serve --addr 0.0.0.0:31415 --sessions /var/lib/subrouter/sessions.json --transcripts /var/lib/subrouter/transcripts --cx-switch-interval 10m
 ```
 
+If legacy `switchboard` or `gateway` services exist, `sr install-systemd` stops and disables them, merges their `/var/lib/...` state into `/var/lib/subrouter`, and preserves their extra service args.
+
 Useful endpoints:
 
 ```text

cmd/subrouter/install_systemd.go

@@ -30,6 +30,7 @@ type systemdConfig struct {
 	Start            bool
 	DryRun           bool
 	InstallAliases   bool
+	ReplaceLegacy    bool
 }
 
 func installSystemd(args []string) error {
@@ -48,6 +49,7 @@ func installSystemd(args []string) error {
 	flags.BoolVar(&config.Start, "start", true, "enable and restart the systemd service")
 	flags.BoolVar(&config.DryRun, "dry-run", false, "print the systemd unit without writing files")
 	flags.BoolVar(&config.InstallAliases, "install-aliases", true, "install sr and cx symlinks to the subrouter binary")
+	flags.BoolVar(&config.ReplaceLegacy, "replace-legacy", true, "stop legacy switchboard/gateway services and migrate their state")
 	if err := flags.Parse(args); err != nil {
 		return err
 	}
@@ -56,6 +58,9 @@ func installSystemd(args []string) error {
 	}
 	if config.ExtraArgs == "" {
 		config.ExtraArgs = readSystemdDefaultExtraArgs(config)
+		if config.ExtraArgs == "" && config.ReplaceLegacy {
+			config.ExtraArgs = readLegacySystemdExtraArgs()
+		}
 	}
 	return installSystemdWithConfig(config, commandRunner{})
 }
@@ -77,6 +82,9 @@ func installSystemdWithConfig(config systemdConfig, runner commandRunner) error
 		return errors.New("install-systemd must run as root; use sudo")
 	}
 
+	if config.ReplaceLegacy {
+		stopLegacySystemdServices(runner)
+	}
 	if err := ensureSystemUser(config, runner); err != nil {
 		return err
 	}
@@ -92,6 +100,9 @@ func installSystemdWithConfig(config systemdConfig, runner commandRunner) error
 			return err
 		}
 	}
+	if config.ReplaceLegacy {
+		migrateLegacySystemdState(config, runner)
+	}
 	if err := installCurrentExecutable(config.InstallPath); err != nil {
 		return err
 	}
@@ -184,13 +195,32 @@ func ensureSystemUser(config systemdConfig, runner commandRunner) error {
 }
 
 func readSystemdDefaultExtraArgs(config systemdConfig) string {
-	body, err := os.ReadFile(systemdDefaultPath(config))
+	return readDefaultValue(systemdDefaultPath(config), "SUBROUTER_EXTRA_ARGS")
+}
+
+func readLegacySystemdExtraArgs() string {
+	for _, legacy := range []struct {
+		path string
+		key  string
+	}{
+		{"/etc/default/switchboard", "SWITCHBOARD_EXTRA_ARGS"},
+		{"/etc/default/gateway", "GATEWAY_EXTRA_ARGS"},
+	} {
+		if value := readDefaultValue(legacy.path, legacy.key); value != "" {
+			return value
+		}
+	}
+	return ""
+}
+
+func readDefaultValue(path, keyName string) string {
+	body, err := os.ReadFile(path)
 	if err != nil {
 		return ""
 	}
 	for _, line := range strings.Split(string(body), "\n") {
 		key, value, ok := strings.Cut(line, "=")
-		if !ok || strings.TrimSpace(key) != "SUBROUTER_EXTRA_ARGS" {
+		if !ok || strings.TrimSpace(key) != keyName {
 			continue
 		}
 		value = strings.TrimSpace(value)
@@ -200,6 +230,24 @@ func readSystemdDefaultExtraArgs(config systemdConfig) string {
 	return ""
 }
 
+func stopLegacySystemdServices(runner commandRunner) {
+	for _, service := range []string{"switchboard", "gateway"} {
+		_ = runner.Run("systemctl", "disable", "--now", service)
+	}
+}
+
+func migrateLegacySystemdState(config systemdConfig, runner commandRunner) {
+	for _, legacyHome := range []string{"/var/lib/switchboard", "/var/lib/gateway"} {
+		if legacyHome == config.Home {
+			continue
+		}
+		if info, err := os.Stat(legacyHome); err != nil || !info.IsDir() {
+			continue
+		}
+		_ = runner.Run("cp", "-a", "-n", legacyHome+"/.", config.Home+"/")
+	}
+}
+
 func systemdDefaultPath(config systemdConfig) string {
 	return filepath.Join("/etc/default", config.ServiceName)
 }

cmd/subrouter/install_systemd_test.go

@@ -1,6 +1,8 @@
 package main
 
 import (
+	"os"
+	"path/filepath"
 	"strings"
 	"testing"
 )
@@ -49,3 +51,15 @@ func TestSystemdDefaultsEscapesExtraArgs(t *testing.T) {
 		t.Fatalf("defaults did not quote extra args:\n%s", defaults)
 	}
 }
+
+func TestReadDefaultValueUnquotesEnvFileValue(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "subrouter")
+	if err := os.WriteFile(path, []byte("SUBROUTER_EXTRA_ARGS=\"--transcript-gcs-uri=gs://bucket/prefix --fetch-usage=false\"\n"), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	got := readDefaultValue(path, "SUBROUTER_EXTRA_ARGS")
+	want := "--transcript-gcs-uri=gs://bucket/prefix --fetch-usage=false"
+	if got != want {
+		t.Fatalf("extra args = %q, want %q", got, want)
+	}
+}

deploy/gcp/README.md

@@ -40,7 +40,7 @@ Install or upgrade Subrouter on the VM:
 deploy/gcp/publish-subrouter.sh
 ```
 
-The publish script configures the server with `sr server add`, then runs `sr server install`. The VM downloads the public release with the same curl installer and runs `sr install-systemd`; no locally built binary is copied to the server.
+The publish script configures the server with `sr server add`, then runs `sr server install`. The VM downloads the public release with the same curl installer and runs `sr install-systemd`; no locally built binary is copied to the server. If legacy `switchboard` or `gateway` services exist on the VM, the systemd installer disables them and migrates their state into `/var/lib/subrouter`.
 
 Join or rejoin the host to Tailscale with an auth key:
 

package.json

@@ -1,6 +1,6 @@
 {
   "name": "subrouter",
-  "version": "0.1.2",
+  "version": "0.1.3",
   "description": "Routes AI coding-agent traffic across subscription accounts and API keys.",
   "license": "MIT",
   "homepage": "https://github.com/manaflow-ai/subrouter#readme",

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "subrouter"
-version = "0.1.2"
+version = "0.1.3"
 description = "Routes AI coding-agent traffic across subscription accounts and API keys."
 readme = "README.md"
 requires-python = ">=3.9"

subrouter_cli/__init__.py

@@ -9,7 +9,7 @@
 import urllib.request
 from pathlib import Path
 
-VERSION = "0.1.2"
+VERSION = "0.1.3"
 
 
 def _go_platform() -> str: