From 2facce8a43f4f6e17296544647a20a527506860e Mon Sep 17 00:00:00 2001
From: Christian Claus <c.claus@micromata.de>
Date: Wed, 11 Apr 2018 13:30:28 +0200
Subject: [PATCH] Add abilities for config live reload and user updates

---
 app/config.go   | 34 ++++++++++++++++++++++++++++++++++
 app/security.go |  2 +-
 2 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/app/config.go b/app/config.go
index 9e79738..622ca70 100644
--- a/app/config.go
+++ b/app/config.go
@@ -5,6 +5,7 @@ import (
 	"github.com/spf13/viper"
 	"log"
 	"os"
+	"github.com/fsnotify/fsnotify"
 )
 
 // Config represents the configuration of the server application.
@@ -57,6 +58,39 @@ func ParseConfig() *Config {
 		}
 	}
 
+	viper.WatchConfig()
+	viper.OnConfigChange(func(e fsnotify.Event) {
+		fmt.Println("Config file changed:", e.Name)
+
+		file, err := os.Open(e.Name)
+		if err != nil {
+			fmt.Println("Error reloading config", e.Name)
+		}
+
+		var updatedCfg = &Config{}
+		viper.ReadConfig(file)
+		viper.Unmarshal(&updatedCfg)
+
+		for k, _ := range cfg.Users {
+			if updatedCfg.Users[k] == nil {
+				fmt.Printf("Removed User from configuration: %s\n", k)
+				cfg.Users[k] = nil
+			}
+		}
+
+		for k, v := range updatedCfg.Users {
+			if cfg.Users[k] == nil {
+				fmt.Printf("Added User to configuration: %s\n", k)
+				cfg.Users[k] = v
+			} else {
+				if cfg.Users[k].Password != v.Password {
+					fmt.Printf("Updated password of user: %s\n", k)
+					cfg.Users[k].Password = v.Password
+				}
+			}
+		}
+	})
+
 	return cfg
 }
 
diff --git a/app/security.go b/app/security.go
index 81d78d7..357c738 100644
--- a/app/security.go
+++ b/app/security.go
@@ -16,7 +16,7 @@ func Authorize(config *Config) auth.SecretProvider {
 			return user.Password
 		}
 
-		fmt.Printf("Username not found: %s", username)
+		fmt.Printf("Username not found: %s\n", username)
 		return ""
 	}
 }