add code and binary programs

Author: ligongxiang

README.md

@@ -1,2 +1,16 @@
 # timestampHelper
-small tool for convert timestamp to string or convert string to timestamp
+
+Small tool for convert timestamp to string or convert string to timestamp.
+
+## Useage
+
+`> timehelper 2019-01-01 1546300800`
+
+timehelper [formatted string date or timestamp] ...
+
+![show](https://ws2.sinaimg.cn/large/006tNc79ly1fyzcyjyqwjj30qo02ugm5.jpg)
+
+##Warning
+
+* formatted date string must be YYYY-MM-DD
+* timestamp must only 10 bits, 13 bits must convert to 10 bits timestamp

go.mod

@@ -0,0 +1 @@
+module timehelper

main.go

@@ -0,0 +1,36 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+	"time"
+)
+
+func main() {
+	list := os.Args
+	if len(list) == 1 {
+		fmt.Println("missing args")
+		os.Exit(1)
+	}
+	result := ""
+	for index, value := range list {
+		//filter script self
+		if index == 0 {
+			continue
+		}
+		//convert to int
+		intValue, err := strconv.Atoi(value)
+		//convert str to timestamp
+		if err != nil {
+			timeStamp, _ := time.Parse("2006-01-02", value)
+			result = strconv.FormatInt(timeStamp.Unix(), 10)
+		} else {
+			//convert timestamp to str
+			tm := time.Unix(int64(intValue), 0)
+			result = tm.Format("2006-01-02 15:04:05")
+		}
+		output := value + " => " + result
+		fmt.Println(output)
+	}
+}