Cascade errors back up to main(), rather than exiting deep in the stack.

cmd/cli/add.go

@@ -9,10 +9,12 @@ import (
 )
 
 // Add prompts for the required information and creates a new peer
-func Add(hostname, owner, description string, confirm bool) {
+func Add(hostname, owner, description string, confirm bool) error {
 	// TODO accept existing pubkey
 	config, err := LoadConfigFile()
-	check(err, "failed to load configuration file")
+	if err != nil {
+		return wrapError(err, "failed to load configuration file")
+	}
 	server := GetServer(config)
 
 	if owner == "" {
@@ -31,7 +33,9 @@ func Add(hostname, owner, description string, confirm bool) {
 	fmt.Fprintln(os.Stderr)
 
 	peer, err := lib.NewPeer(server, owner, hostname, description)
-	check(err, "failed to get new peer")
+	if err != nil {
+		return wrapError(err, "failed to get new peer")
+	}
 
 	// TODO Some kind of recovery here would be nice, to avoid
 	// leaving things in a potential broken state
@@ -41,12 +45,17 @@ func Add(hostname, owner, description string, confirm bool) {
 	peerType := viper.GetString("output")
 
 	peerConfigBytes, err := lib.AsciiPeerConfig(peer, peerType, *server)
-	check(err, "failed to get peer configuration")
+	if err != nil {
+		return wrapError(err, "failed to get peer configuration")
+	}
 	os.Stdout.Write(peerConfigBytes.Bytes())
 
 	config.MustSave()
 
 	server = GetServer(config)
 	err = server.ConfigureDevice()
-	check(err, "failed to configure device")
+	if err != nil {
+		return wrapError(err, "failed to configure device")
+	}
+	return nil
 }

cmd/cli/regenerate.go

@@ -8,7 +8,7 @@ import (
 	"github.com/spf13/viper"
 )
 
-func Regenerate(hostname string, confirm bool) {
+func Regenerate(hostname string, confirm bool) error {
 	config := MustLoadConfigFile()
 	server := GetServer(config)
 
@@ -21,22 +21,30 @@ func Regenerate(hostname string, confirm bool) {
 	for _, peer := range server.Peers {
 		if peer.Hostname == hostname {
 			privateKey, err := lib.GenerateJSONPrivateKey()
-			check(err, "failed to generate private key")
+			if err != nil {
+				return wrapError(err, "failed to generate private key")
+			}
 
 			preshareKey, err := lib.GenerateJSONKey()
-			check(err, "failed to generate preshared key")
+			if err != nil {
+				return wrapError(err, "failed to generate preshared key")
+			}
 
 			peer.PrivateKey = privateKey
 			peer.PublicKey = privateKey.PublicKey()
 			peer.PresharedKey = preshareKey
 
 			err = config.RemovePeer(hostname)
-			check(err, "failed to regenerate peer")
+			if err != nil {
+				return wrapError(err, "failed to regenerate peer")
+			}
 
 			peerType := viper.GetString("output")
 
 			peerConfigBytes, err := lib.AsciiPeerConfig(peer, peerType, *server)
-			check(err, "failed to get peer configuration")
+			if err != nil {
+				return wrapError(err, "failed to get peer configuration")
+			}
 			os.Stdout.Write(peerConfigBytes.Bytes())
 			found = true
 			config.MustAddPeer(peer)
@@ -46,11 +54,12 @@ func Regenerate(hostname string, confirm bool) {
 	}
 
 	if !found {
-		ExitFail(fmt.Sprintf("unknown hostname: %s", hostname))
+		return fmt.Errorf("unknown hostname: %s", hostname)
 	}
 
 	// Get a new server configuration so we can update the wg interface with the new peer details
 	server = GetServer(config)
 	config.MustSave()
 	server.ConfigureDevice()
+	return nil
 }

cmd/cli/remove.go

@@ -2,11 +2,13 @@ package cli
 
 import "fmt"
 
-func Remove(hostname string, confirm bool) {
+func Remove(hostname string, confirm bool) error {
 	conf := MustLoadConfigFile()
 
 	err := conf.RemovePeer(hostname)
-	check(err, "failed to update config")
+	if err != nil {
+		return wrapError(err, "failed to update config")
+	}
 
 	if !confirm {
 		ConfirmOrAbort("Do you really want to remove %s?", hostname)
@@ -16,5 +18,8 @@ func Remove(hostname string, confirm bool) {
 	server := GetServer(conf)
 
 	err = server.ConfigureDevice()
-	check(err, fmt.Sprintf("failed to sync server config to wg interface: %s", server.InterfaceName))
+	if err != nil {
+		return wrapError(err, fmt.Sprintf("failed to sync server config to wg interface: %s", server.InterfaceName))
+	}
+	return nil
 }

cmd/cli/report.go

@@ -2,6 +2,7 @@ package cli
 
 import (
 	"encoding/json"
+	"fmt"
 	"io/ioutil"
 	"net"
 	"os"
@@ -69,7 +70,7 @@ type PeerReport struct {
 	TransmitBytesSI   string
 }
 
-func GenerateReport() {
+func GenerateReport() error {
 	conf := MustLoadConfigFile()
 
 	wg, err := wgctrl.New()
@@ -79,12 +80,13 @@ func GenerateReport() {
 	dev, err := wg.Device(conf.InterfaceName)
 
 	if err != nil {
-		ExitFail("Could not retrieve device '%s' (%v)", conf.InterfaceName, err)
+		return wrapError(err, fmt.Sprintf("Could not retrieve device '%s'", conf.InterfaceName))
 	}
 
 	oldReport := MustLoadDsnetReport()
 	report := GetReport(dev, conf, oldReport)
 	report.MustSave()
+	return nil
 }
 
 func GetReport(dev *wgtypes.Device, conf *DsnetConfig, oldReport *DsnetReport) DsnetReport {

cmd/cli/sync.go

@@ -1,10 +1,15 @@
 package cli
 
-func Sync() {
+func Sync() error {
 	// TODO check device settings first
 	conf, err := LoadConfigFile()
-	check(err, "failed to load configuration file")
+	if err != nil {
+		return wrapError(err, "failed to load configuration file")
+	}
 	server := GetServer(conf)
 	err = server.ConfigureDevice()
-	check(err, "failed to sync device configuration")
+	if err != nil {
+		return wrapError(err, "failed to sync device configuration")
+	}
+	return nil
 }

cmd/cli/util.go

@@ -42,6 +42,10 @@ func ExitFail(format string, a ...interface{}) {
 	os.Exit(1)
 }
 
+func wrapError(err error, s string) error {
+	return fmt.Errorf("\033[31m%s - %s\033[0m\n", err, s)
+}
+
 func MustPromptString(prompt string, required bool) string {
 	reader := bufio.NewReader(os.Stdin)
 	var text string

cmd/root.go

@@ -76,8 +76,8 @@ var (
 			}
 			return nil
 		},
-		Run: func(cmd *cobra.Command, args []string) {
-			cli.Add(args[0], owner, description, confirm)
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return cli.Add(args[0], owner, description, confirm)
 		},
 	}
 
@@ -90,24 +90,24 @@ var (
 			}
 			return nil
 		},
-		Run: func(cmd *cobra.Command, args []string) {
-			cli.Regenerate(args[0], confirm)
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return cli.Regenerate(args[0], confirm)
 		},
 	}
 
 	syncCmd = &cobra.Command{
 		Use:   "sync",
 		Short: fmt.Sprintf("Update wireguard configuration from %s after validating", viper.GetString("config_file")),
-		Run: func(cmd *cobra.Command, args []string) {
-			cli.Sync()
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return cli.Sync()
 		},
 	}
 
 	reportCmd = &cobra.Command{
 		Use:   "report",
 		Short: fmt.Sprintf("Generate a JSON status report to the location configured in %s.", viper.GetString("config_file")),
-		Run: func(cmd *cobra.Command, args []string) {
-			cli.GenerateReport()
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return cli.GenerateReport()
 		},
 	}
 
@@ -122,8 +122,8 @@ var (
 
 			return nil
 		},
-		Run: func(cmd *cobra.Command, args []string) {
-			cli.Remove(args[0], confirm)
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return cli.Remove(args[0], confirm)
 		},
 	}
 
@@ -181,8 +181,5 @@ func main() {
 	if err := rootCmd.Execute(); err != nil {
 		cli.ExitFail(err.Error())
 	}
-	if error_encountered {
-		os.Exit(1)
-	}
 	os.Exit(0)
 }