retry init

main.go

@@ -98,6 +98,8 @@ type CLIArgs struct {
 	bootstrapDNS        *CSVArg
 	refresh             time.Duration
 	refreshRetry        time.Duration
+	initRetries         int
+	initRetryInterval   time.Duration
 	certChainWorkaround bool
 	caFile              string
 }
@@ -140,6 +142,8 @@ func parse_args() *CLIArgs {
 			"Examples: https://1.1.1.1/dns-query,quic://dns.adguard.com")
 	flag.DurationVar(&args.refresh, "refresh", 4*time.Hour, "login refresh interval")
 	flag.DurationVar(&args.refreshRetry, "refresh-retry", 5*time.Second, "login refresh retry interval")
+	flag.IntVar(&args.initRetries, "init-retries", 0, "initialization steps attempts, zero for unlimited retry")
+	flag.DurationVar(&args.initRetryInterval, "init-retry-interval", 5 * time.Second, "delay between initialization retries")
 	flag.BoolVar(&args.certChainWorkaround, "certchain-workaround", true,
 		"add bundled cross-signed intermediate cert to certchain to make it check out on old systems")
 	flag.StringVar(&args.caFile, "cafile", "", "use custom CA certificate bundle file")
@@ -237,39 +241,48 @@ func run() int {
 		TLSHandshakeTimeout:   10 * time.Second,
 		ExpectContinueTimeout: 1 * time.Second,
 	})
-	seclient.Settings.ClientType = args.apiClientType
-	seclient.Settings.ClientVersion = args.apiClientVersion
-	seclient.Settings.UserAgent = args.apiUserAgent
 	if err != nil {
 		mainLogger.Critical("Unable to construct SEClient: %v", err)
 		return 8
 	}
+	seclient.Settings.ClientType = args.apiClientType
+	seclient.Settings.ClientVersion = args.apiClientVersion
+	seclient.Settings.UserAgent = args.apiUserAgent
 
-	ctx, cl := context.WithTimeout(context.Background(), args.timeout)
+	try := retryPolicy(args.initRetries, args.initRetryInterval, mainLogger)
-	err = seclient.AnonRegister(ctx)
+
+	err = try("anonymous registration", func() error {
+		ctx, cl := context.WithTimeout(context.Background(), args.timeout)
+		defer cl()
+		return seclient.AnonRegister(ctx)
+	})
 	if err != nil {
-		mainLogger.Critical("Unable to perform anonymous registration: %v", err)
 		return 9
 	}
-	cl()
 
-	ctx, cl = context.WithTimeout(context.Background(), args.timeout)
+	err = try("device registration", func() error {
-	err = seclient.RegisterDevice(ctx)
+		ctx, cl := context.WithTimeout(context.Background(), args.timeout)
+		defer cl()
+		return seclient.RegisterDevice(ctx)
+	})
 	if err != nil {
-		mainLogger.Critical("Unable to perform device registration: %v", err)
 		return 10
 	}
-	cl()
 
 	if args.listCountries {
-		return printCountries(mainLogger, args.timeout, seclient)
+		return printCountries(try, mainLogger, args.timeout, seclient)
 	}
 
-	ctx, cl = context.WithTimeout(context.Background(), args.timeout)
+	var ips []se.SEIPEntry
-	// TODO: learn about requested_geo value format
+	err = try("discover", func() error {
-	ips, err := seclient.Discover(ctx, fmt.Sprintf("\"%s\",,", args.country))
+		ctx, cl := context.WithTimeout(context.Background(), args.timeout)
+		defer cl()
+		// TODO: learn about requested_geo value format
+		res, err := seclient.Discover(ctx, fmt.Sprintf("\"%s\",,", args.country))
+		ips = res
+		return err
+	})
 	if err != nil {
-		mainLogger.Critical("Endpoint discovery failed: %v", err)
 		return 12
 	}
 
@@ -340,12 +353,16 @@ func run() int {
 	return 0
 }
 
-func printCountries(logger *clog.CondLogger, timeout time.Duration, seclient *se.SEClient) int {
+func printCountries(try func(string, func() error) error, logger *clog.CondLogger, timeout time.Duration, seclient *se.SEClient) int {
-	ctx, cl := context.WithTimeout(context.Background(), timeout)
+	var list []se.SEGeoEntry
-	defer cl()
+	err := try("geolist", func() error {
-	list, err := seclient.GeoList(ctx)
+		ctx, cl := context.WithTimeout(context.Background(), timeout)
+		defer cl()
+		l, err := seclient.GeoList(ctx)
+		list = l
+		return err
+	})
 	if err != nil {
-		logger.Critical("GeoList error: %v", err)
 		return 11
 	}
 
@@ -382,3 +399,24 @@ func printProxies(ips []se.SEIPEntry, seclient *se.SEClient) int {
 func main() {
 	os.Exit(run())
 }
+
+func retryPolicy(retries int, retryInterval time.Duration, logger *clog.CondLogger) func(string, func() error) error {
+	return func(name string, f func() error) error {
+		var err error
+		for i:=1; retries <= 0 || i<=retries; i++ {
+			if i > 1 {
+				logger.Warning("Retrying action %q in %v...", name, retryInterval)
+				time.Sleep(retryInterval)
+			}
+			logger.Info("Attempting action %q, attempt #%d...", name, i)
+			err = f()
+			if err == nil {
+				logger.Info("Action %q succeeded on attempt #%d", name, i)
+				return nil
+			}
+			logger.Warning("Action %q failed: %v", name, err)
+		}
+		logger.Critical("All attempts for action %q have failed. Last error: %v", name, err)
+		return err
+	}
+}