[PLAT-15031] yba installer os patch guardrails

Summary:
Implemented 2 guardrails to help with --without-data install.
First, we have a new .version file in the data directory. This file will
be used to ensure an older YBA does not start against a newer data file.

In addition, the data disk size only runs when required, and on the
data directory directly

Test Plan:
tested various combinations of version file vs a yba version
tested using --without-data to upgrade yba

Reviewers: muthu, sanketh

Reviewed By: muthu

Subscribers: yugaware

Differential Revision: https://phorge.dev.yugabyte.com/D37818

managed/yba-installer/cmd/install.go

@@ -61,6 +61,9 @@ var installCmd = &cobra.Command{
 
 		// Preflight checks
 		// TODO: Add preflight checks for ybdb.
+		if dataless {
+			skippedPreflightChecks = append(skippedPreflightChecks, "disk-availability")
+		}
 		var results *checks.MappedResults
 		if common.IsPostgresEnabled() {
 			results = preflight.Run(preflight.InstallChecksWithPostgres, skippedPreflightChecks...)

managed/yba-installer/cmd/preflight.go

@@ -48,6 +48,9 @@ var preflightCmd = &cobra.Command{
 			}
 			// TODO: We should allow the user to better specify which checks to run.
 			// Will do this as we implement a set of upgrade preflight checks
+			if dataless {
+				skippedPreflightChecks = append(skippedPreflightChecks, "disk-availability")
+			}
 			results := preflight.Run(checksToRun, skippedPreflightChecks...)
 			preflight.PrintPreflightResults(results)
 			if preflight.ShouldFail(results) {

managed/yba-installer/cmd/service_control.go

@@ -6,6 +6,8 @@ import (
 	"github.com/spf13/cobra"
 	"github.com/yugabyte/yugabyte-db/managed/yba-installer/pkg/common"
 	log "github.com/yugabyte/yugabyte-db/managed/yba-installer/pkg/logging"
+	"github.com/yugabyte/yugabyte-db/managed/yba-installer/pkg/preflight"
+	"github.com/yugabyte/yugabyte-db/managed/yba-installer/pkg/preflight/checks"
 	"github.com/yugabyte/yugabyte-db/managed/yba-installer/pkg/ybactlstate"
 )
 
@@ -36,7 +38,15 @@ var startCmd = &cobra.Command{
 			log.Fatal("cannot start services - need installed state got " +
 				state.CurrentStatus.String())
 		}
+
+		// Initialize if it has not already happened. Do this instead of normal start workflow
 		if !state.Initialized {
+			// Run preflight check for data directory size if we have to initialize.
+			results := preflight.Run([]preflight.Check{checks.DiskAvail})
+			preflight.PrintPreflightResults(results)
+			if preflight.ShouldFail(results) {
+				log.Fatal("preflight failed")
+			}
 			log.Info("Initializing YBA before starting services")
 			if err := common.Initialize(); err != nil {
 				log.Fatal("Failed to initialize common components: " + err.Error())
@@ -57,6 +67,10 @@ var startCmd = &cobra.Command{
 			// We can exit early, as initialize will also start the services
 			return
 		}
+
+		if err := common.CheckDataVersionFile(); err != nil {
+			log.Fatal("Failed to validate data version: " + err.Error())
+		}
 		if len(args) == 1 {
 			if err := services[args[0]].Start(); err != nil {
 				log.Fatal("Failed to start " + args[0] + ": " + err.Error())

managed/yba-installer/pkg/common/common.go

@@ -104,6 +104,11 @@ func Initialize() error {
 		return err
 	}
 
+	// Validate or create the data version file.
+	if err := CheckOrCreateDataVersionFile(); err != nil {
+		return err
+	}
+
 	// Generate certs if required.
 	var serverCertPath, serverKeyPath string
 	if len(viper.GetString("server_cert_path")) == 0 {
@@ -171,6 +176,34 @@ func CreateDirs(createDirs []string) error {
 	return nil
 }
 
+// CheckOrCreateDataVersionFile checks if the YBA Version is older than the data version file. This is not
+// supported as an older YBA cannot run with newer data due to PG migrations. If the file does not
+// exist, it will instead create it with the current version
+func CheckOrCreateDataVersionFile() error {
+	_, err := os.Stat(DataVersionFile())
+	if os.IsNotExist(err) {
+		return os.WriteFile(DataVersionFile(), []byte(Version), 0644)
+	}
+	return CheckDataVersionFile()
+}
+
+// CheckDataVersionFile checks if the YBA Version is older than the data version file. This is not
+// supported as an older YBA cannot run with newer data due to PG migrations
+func CheckDataVersionFile() error {
+	buf, err := os.ReadFile(DataVersionFile())
+	if !os.IsNotExist(err) {
+		if err != nil {
+			return fmt.Errorf("could not open data version file: %w", err)
+		}
+		dataVersion := strings.TrimSpace(string(buf))
+		if LessVersions(Version, dataVersion) {
+			return fmt.Errorf("YBA version %s is older than data version %s", Version, dataVersion)
+		}
+	}
+	// Update to the latest version.
+	return os.WriteFile(DataVersionFile(), []byte(Version), 0644)
+}
+
 // Copies over necessary files for all services from yba_installer_full to the GetSoftwareRoot()
 func copyBits(vers string) error {
 	yugabundleBinary := "yugabundle-" + vers + "-centos-x86_64.tar.gz"

managed/yba-installer/pkg/common/directory_manager.go

@@ -38,10 +38,9 @@ import (
 
 // ALl of our install files and directories.
 const (
-	//installMarkerName string = ".install_marker"
-	//installLocationOne string = "one"
-	//installLocationTwo string = "two"
 	InstallSymlink string = "active"
+
+	dataVersionFileName = ".version.txt"
 )
 
 // Directory names for config files
@@ -73,6 +72,10 @@ func GetDataRoot() string {
 	return filepath.Join(dm.BaseInstall(), "data")
 }
 
+func DataVersionFile() string {
+	return filepath.Join(GetDataRoot(), dataVersionFileName)
+}
+
 // GetInstallRoot returns the InstallRoot where YBA is installed.
 func GetSoftwareRoot() string {
 	return dm.WorkingDirectory()

managed/yba-installer/pkg/preflight/checks/diskavail.go

@@ -46,7 +46,7 @@ func (r diskAvailCheck) Execute() Result {
 		Status: StatusPassed,
 	}
 
-	baseDir := common.GetBaseInstall()
+	baseDir := common.GetDataRoot()
 	bytesAvail, err := getFreeBytes(baseDir)
 	if err != nil {
 		res.Error = err