Adding common flags

cmd/publisher/main.go

@@ -1,7 +1,13 @@
 package main
 
-import "fmt"
+import (
+	"flag"
+	"fmt"
+
+	"git.runcible.io/learning/learn_mqtt_go/common"
+)
 
 func main() {
-	fmt.Println("MQTT Publisher")
+	flag.Parse()
+	fmt.Printf("MQTT Host: %s\nMQTT Port: %s\n", *common.BrokerHost, *common.BrokerPort)
 }

cmd/subscriber/main.go

@@ -1,7 +1,13 @@
 package main
 
-import "fmt"
+import (
+	"flag"
+	"fmt"
+
+	"git.runcible.io/learning/learn_mqtt_go/common"
+)
 
 func main() {
-	fmt.Println("MQTT Subscriber")
+	flag.Parse()
+	fmt.Printf("MQTT Host: %s\nMQTT Port: %s\n", *common.BrokerHost, *common.BrokerPort)
 }

common/common.go

@@ -1,6 +1,9 @@
 package common
 
-import "os"
+import (
+	"flag"
+	"os"
+)
 
 // GetenvDefault retrieves an environment variable if set, or a provided default
 func GetenvDefault(key string, defaultValue string) string {
@@ -11,3 +14,9 @@ func GetenvDefault(key string, defaultValue string) string {
 		return defaultValue
 	}
 }
+
+// For now just assume all values source from flags are strings
+var (
+	BrokerHost = flag.String("host", GetenvDefault("RUN_MQTT_HOST", "localhost"), "Hostname or IP address to an MQTT broker")
+	BrokerPort = flag.String("port", GetenvDefault("RUN_MQTT_PORT", "1883"), "Port to an MQTT broker")
+)