FAB-7769 if FABRIC_CFG_PATH invalid, peer panic

if FABRIC_CFG_PATH set to non existant directory,
peer panics

Change-Id: Ia162dd7f9c49fcec25005f27a87a839f6fddb75a
Signed-off-by: John D Sheehan <john.d.sheehan@gmail.com>

core/config/config.go

@@ -140,6 +140,11 @@ func InitViper(v *viper.Viper, configName string) error {
 	if altPath != "" {
 		// If the user has overridden the path with an envvar, its the only path
 		// we will consider
+
+		if !dirExists(altPath) {
+			return fmt.Errorf("FABRIC_CFG_PATH %s does not exist", altPath)
+		}
+
 		addConfigPath(v, altPath)
 	} else {
 		// If we get here, we should use the default paths in priority order:

peer/common/common.go

@@ -70,10 +70,13 @@ func init() {
 
 //InitConfig initializes viper config
 func InitConfig(cmdRoot string) error {
-	config.InitViper(nil, cmdRoot)
+	err := config.InitViper(nil, cmdRoot)
+	if err != nil {
+		return err
+	}
 
-	err := viper.ReadInConfig() // Find and read the config file
-	if err != nil {             // Handle errors reading the config file
+	err = viper.ReadInConfig() // Find and read the config file
+	if err != nil {            // Handle errors reading the config file
 		return errors.WithMessage(err, fmt.Sprintf("error when reading %s config file", cmdRoot))
 	}
 

peer/main.go

@@ -72,17 +72,18 @@ func main() {
 	mainFlags.String("logging-level", "", "Default logging level and overrides, see core.yaml for full syntax")
 	viper.BindPFlag("logging_level", mainFlags.Lookup("logging-level"))
 
-	err := common.InitConfig(cmdRoot)
-	if err != nil { // Handle errors reading the config file
-		panic(fmt.Errorf("Fatal error when initializing %s config : %s\n", cmdRoot, err))
-	}
-
 	mainCmd.AddCommand(version.Cmd())
 	mainCmd.AddCommand(node.Cmd())
 	mainCmd.AddCommand(chaincode.Cmd(nil))
 	mainCmd.AddCommand(clilogging.Cmd(nil))
 	mainCmd.AddCommand(channel.Cmd(nil))
 
+	err := common.InitConfig(cmdRoot)
+	if err != nil { // Handle errors reading the config file
+		logger.Errorf("Fatal error when initializing %s config : %s", cmdRoot, err)
+		os.Exit(1)
+	}
+
 	runtime.GOMAXPROCS(viper.GetInt("peer.gomaxprocs"))
 
 	// setup system-wide logging backend based on settings from core.yaml