added configuration via json config-file and logging

.gitignore

@@ -13,3 +13,4 @@
 
 # IDEA
 .idea/
+config.json

main/config.go

@@ -0,0 +1,29 @@
+package main
+
+import (
+	"encoding/json"
+	"io/ioutil"
+	"log"
+)
+
+// configuration of the client
+type Config struct {
+	Tenant   string `json:"tenant"`
+	Password string `json:"password"`
+}
+
+func (c *Config) Load(filename string) {
+	// read the configuration file
+	contextBytes, err := ioutil.ReadFile(filename)
+	if err != nil {
+		log.Fatalf("ERROR: unable to read configuration: %v", err)
+	}
+
+	// parse json configuration
+	err = json.Unmarshal(contextBytes, c)
+	if err != nil {
+		log.Fatalf("ERROR: unable to parse configuration: %v", err)
+	}
+
+	log.Printf("configuration found")
+}

main/main.go

@@ -3,15 +3,27 @@ package main
 import (
 	"fmt"
 	"github.com/ubirch/ubirch-go-c8y-client/c8y"
+	"log"
 )
 
+const ConfigFile = "config.json"
+
 func main() {
-	tenant := "ubirch"
-	c8yPassword := "---"
+	log.Println("UBIRCH Golang Cumulocity client")
+
+	// read configuration
+	conf := Config{}
+	conf.Load(ConfigFile)
+
+	tenant := conf.Tenant
+	c8yPassword := conf.Password
+
+	// bootstrap
 	c8yAuth, err := c8y.C8yBootstrap(tenant, c8yPassword)
 	if err != nil {
-		panic(fmt.Sprintf("unable to bootstrap device: %v", err))
+		fmt.Printf(tenant + " : " + c8yPassword)
+		log.Fatalf("unable to bootstrap device: %v", err)
 	}
 
-	fmt.Printf(c8yAuth)
+	fmt.Printf(tenant + " : " + c8yPassword + " : " + c8yAuth)
 }