handleconfig: deprecate 'timer.use.config.checkpoint' usage

The default behaviour is to fetch saved config if its modification time
does not exceed some stale config time (timer.use.config.checkpoint).
This leads to the following problem observed by the customer:

   1. EVE node and an app are up running.
   2. Connection to the controller is lost for time > timer.use.config.checkpoint,
      so that last saved config modification time has not been updated.
   3. Node is rebooted, connection to the controller is still missing.
   4. Config is being fetched from a file, but modification time has not
      been updated for a while, thus config is rejected and applications
      do not show up.

Although the default setting for the timer is 7 days, it is not enough
for the node which constantly has problems with the internet and which
up-time is minimum, so it is not uncommon to have a last saved config
with the modification time dated several weeks from now.

This is not safe and having outdated config (basically this is always
the case, because there is always a time gap between actual config on
controller and config on EVE) is better, than to have no config at all.

This patch deprecates the 'timer.use.config.checkpoint' and config
is being always read from the file regardless of the modification time.

Kudos to Siddharth and Daniel for debugging this.

Signed-off-by: Roman Penyaev <[email protected]>

Author: rouming

pkg/pillar/cmd/zedagent/handleProfile.go

@@ -97,8 +97,7 @@ func parseLocalProfile(localProfileBytes []byte) (*profile.LocalProfile, error)
 // read saved local profile in case of particular reboot reason
 func readSavedLocalProfile(getconfigCtx *getconfigContext) (*profile.LocalProfile, error) {
 	localProfileMessage, ts, err := readSavedConfig(
-		getconfigCtx.zedagentCtx.globalConfig.GlobalValueInt(types.StaleConfigTime),
-		filepath.Join(checkpointDirname, savedLocalProfileFile), false)
+		filepath.Join(checkpointDirname, savedLocalProfileFile))
 	if err != nil {
 		return nil, fmt.Errorf("readSavedLocalProfile: %v", err)
 	}

pkg/pillar/cmd/zedagent/handleconfig.go

@@ -540,9 +540,7 @@ func getLatestConfig(getconfigCtx *getconfigContext, url string,
 					ctx.bootReason)
 			} else {
 				config, ts, err := readSavedProtoMessageConfig(
-					zedcloudCtx, url,
-					ctx.globalConfig.GlobalValueInt(types.StaleConfigTime),
-					checkpointDirname+"/lastconfig", false)
+					zedcloudCtx, url, checkpointDirname+"/lastconfig")
 				if err != nil {
 					log.Errorf("getconfig: %v", err)
 					return invalidConfig
@@ -709,8 +707,8 @@ func existsSavedConfig(filename string) bool {
 // If the file exists then read the config, and return is modify time
 // Ignore if older than StaleConfigTime seconds
 func readSavedProtoMessageConfig(zedcloudCtx *zedcloud.ZedCloudContext, URL string,
-	staleConfigTime uint32, filename string, force bool) (*zconfig.EdgeDevConfig, time.Time, error) {
-	contents, ts, err := readSavedConfig(staleConfigTime, filename, force)
+	filename string) (*zconfig.EdgeDevConfig, time.Time, error) {
+	contents, ts, err := readSavedConfig(filename)
 	if err != nil {
 		log.Errorln("readSavedProtoMessageConfig", err)
 		return nil, ts, err
@@ -733,24 +731,10 @@ func readSavedProtoMessageConfig(zedcloudCtx *zedcloud.ZedCloudContext, URL stri
 }
 
 // If the file exists then read the config content from it, and return its modify time.
-// Ignore if older than staleTime seconds.
-func readSavedConfig(staleTime uint32,
-	filename string, force bool) ([]byte, time.Time, error) {
+func readSavedConfig(filename string) ([]byte, time.Time, error) {
 	info, err := os.Stat(filename)
 	if err != nil {
-		if os.IsNotExist(err) && !force {
-			return nil, time.Time{}, nil
-		} else {
-			return nil, time.Time{}, err
-		}
-	}
-	age := time.Since(info.ModTime())
-	staleLimit := time.Second * time.Duration(staleTime)
-	if !force && age > staleLimit {
-		errStr := fmt.Sprintf("saved config too old: age %v limit %d\n",
-			age, staleLimit)
-		log.Errorln(errStr)
-		return nil, info.ModTime(), nil
+		return nil, time.Time{}, err
 	}
 	contents, err := ioutil.ReadFile(filename)
 	if err != nil {

pkg/pillar/cmd/zedagent/localinfo.go

@@ -457,8 +457,7 @@ func findAppInstance(
 func readSavedLocalCommands(ctx *getconfigContext) (*types.LocalCommands, error) {
 	commands := &types.LocalCommands{}
 	contents, ts, err := readSavedConfig(
-		ctx.zedagentCtx.globalConfig.GlobalValueInt(types.StaleConfigTime),
-		filepath.Join(checkpointDirname, savedLocalCommandsFile), false)
+		filepath.Join(checkpointDirname, savedLocalCommandsFile))
 	if err != nil {
 		return commands, err
 	}

pkg/pillar/cmd/zedagent/radiosilence.go

@@ -228,8 +228,7 @@ func getRadioConfig(ctx *getconfigContext, radioStatus *profile.RadioStatus) *pr
 // read saved radio config in case of a reboot
 func readSavedRadioConfig(ctx *getconfigContext) (*profile.RadioConfig, error) {
 	radioConfigBytes, ts, err := readSavedConfig(
-		ctx.zedagentCtx.globalConfig.GlobalValueInt(types.StaleConfigTime),
-		filepath.Join(checkpointDirname, savedRadioConfigFile), false)
+		filepath.Join(checkpointDirname, savedRadioConfigFile))
 	if err != nil {
 		return nil, fmt.Errorf("readSavedRadioConfig: %v", err)
 	}

pkg/pillar/cmd/zedagent/validate.go

@@ -10,10 +10,9 @@ import (
 	zconfig "github.com/lf-edge/eve/api/go/config"
 )
 
-func readValidateConfig(staleConfigTime uint32,
-	validateFile string) (bool, *zconfig.EdgeDevConfig) {
+func readValidateConfig(validateFile string) (bool, *zconfig.EdgeDevConfig) {
 	config, _, err := readSavedProtoMessageConfig(zedcloudCtx, "https://",
-		staleConfigTime, validateFile, true)
+		validateFile)
 	if err != nil {
 		fmt.Printf("getconfig: %v\n", err)
 		return false, nil

pkg/pillar/cmd/zedagent/zedagent.go

@@ -257,8 +257,7 @@ func Run(ps *pubsub.PubSub, loggerArg *logrus.Logger, logArg *base.LogObject, ar
 		return 1
 	}
 	if parse != "" {
-		res, config := readValidateConfig(
-			types.DefaultConfigItemValueMap().GlobalValueInt(types.StaleConfigTime), parse)
+		res, config := readValidateConfig(parse)
 		if !res {
 			fmt.Printf("Failed to parse %s\n", parse)
 			return 1

pkg/pillar/types/global.go

@@ -167,6 +167,7 @@ const (
 	// MintimeUpdateSuccess global setting key
 	MintimeUpdateSuccess GlobalSettingKey = "timer.test.baseimage.update"
 	// StaleConfigTime global setting key
+	// DEPRECATED! Saved config never expires!
 	StaleConfigTime GlobalSettingKey = "timer.use.config.checkpoint"
 	// VdiskGCTime global setting key
 	VdiskGCTime GlobalSettingKey = "timer.gc.vdisk"
@@ -789,6 +790,7 @@ func NewConfigItemSpecMap() ConfigItemSpecMap {
 	configItemSpecMap.AddIntItem(ResetIfCloudGoneTime, 7*24*3600, 120, 0xFFFFFFFF)
 	configItemSpecMap.AddIntItem(FallbackIfCloudGoneTime, 300, 60, 0xFFFFFFFF)
 	configItemSpecMap.AddIntItem(MintimeUpdateSuccess, 600, 30, HourInSec)
+	// DEPRECATED
 	configItemSpecMap.AddIntItem(StaleConfigTime, 7*24*3600, 0, 0xFFFFFFFF)
 	configItemSpecMap.AddIntItem(VdiskGCTime, 3600, 60, 0xFFFFFFFF)
 	configItemSpecMap.AddIntItem(DeferContentDelete, 0, 0, 24*3600)

pkg/pillar/types/globalconfigold.go

@@ -107,7 +107,7 @@ var globalConfigDefaults = OldGlobalConfig{
 	UsbAccess:           true, // Controller likely to default to false
 	SshAccess:           true, // Controller likely to default to false
 	SshAuthorizedKeys:   "",
-	StaleConfigTime:     600,  // Use stale config for up to 10 minutes
+	StaleConfigTime:     600,  // DEPRECATED!
 	DownloadGCTime:      600,  // 10 minutes
 	VdiskGCTime:         3600, // 1 hour
 	DownloadRetryTime:   600,  // 10 minutes