allow the use of a config file instead of manually pasting configs

examples/basic/bot.config.yml

@@ -0,0 +1,5 @@
+verify_token: <verify_token_here>
+access_token: <access_token_here>
+app_secret: <app_secret_here>
+
+# other configs can be added as necessary. For example, the webhook URL and host.

examples/basic/main.go

@@ -8,16 +8,18 @@ import (
 	"os"
 	"time"
 
+	msgs "github.com/messenger"
 	"github.com/paked/messenger"
 )
 
+var vt, acct, appsc = msgs.GetTokens()
 var (
-	verifyToken = flag.String("verify-token", "mad-skrilla", "The token used to verify facebook (required)")
+	verifyToken = flag.String("verify-token", vt, "The token used to verify facebook (required)")
 	verify      = flag.Bool("should-verify", false, "Whether or not the app should verify itself")
-	pageToken   = flag.String("page-token", "not skrilla", "The token that is used to verify the page on facebook")
+	pageToken   = flag.String("page-token", acct, "The token that is used to verify the page on facebook")
-	appSecret   = flag.String("app-secret", "", "The app secret from the facebook developer portal (required)")
+	appSecret   = flag.String("app-secret", appsc, "The app secret from the facebook developer portal (required)")
 	host        = flag.String("host", "localhost", "The host used to serve the messenger bot")
-	port        = flag.Int("port", 8080, "The port used to serve the messenger bot")
+	port        = flag.Int("port", 5000, "The port used to serve the messenger bot")
 )
 
 func main() {

parser.go

@@ -0,0 +1,45 @@
+package messenger
+
+import (
+	"io/ioutil"
+	"log"
+	"os"
+	"path/filepath"
+
+	"gopkg.in/yaml.v2"
+)
+
+//Config is the struct for the configuration file
+type Config struct {
+	VerifyToken string `yaml:"verify_token"`
+	AccessToken string `yaml:"access_token"`
+	AppSecret   string `yaml:"app_secret"`
+}
+
+//ReadYml parses the config yml file and format into the Config struct
+func (x *Config) ReadYml() *Config {
+	configFile, err := filepath.Abs("./bot.config.yml")
+	if err != nil {
+		log.Printf("ERROR READING THE CONFIG FILE: %s", err)
+	}
+
+	yamlFile, err := ioutil.ReadFile(configFile)
+
+	if err != nil {
+		log.Println("Could not find the config file. Please make sure it is created", err)
+		os.Exit(-1)
+	}
+
+	yaml.Unmarshal(yamlFile, &x)
+
+	return x
+}
+
+//GetTokens returns the verifytoken, accesstoken and the appsecret from the config file
+func GetTokens() (string, string, string) {
+	var c Config
+
+	configObj := c.ReadYml()
+	verifyToken, accessToken, appSecret := configObj.VerifyToken, configObj.AccessToken, configObj.AppSecret
+	return verifyToken, accessToken, appSecret
+}