Add firebase support

util/util.go

@@ -0,0 +1,29 @@
+package util
+
+import (
+	"math/rand"
+	"os"
+	"time"
+)
+
+const (
+	randomStringCharset = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
+)
+
+var (
+	random = rand.New(rand.NewSource(time.Now().UnixNano()))
+)
+
+func FileExists(filename string) bool {
+	stat, _ := os.Stat(filename)
+	return stat != nil
+}
+
+// RandomString returns a random string with a given length
+func RandomString(length int) string {
+	b := make([]byte, length)
+	for i := range b {
+		b[i] = randomStringCharset[random.Intn(len(randomStringCharset))]
+	}
+	return string(b)
+}