CMD: Time-based UUID Generator & Parser

LICENSE

@@ -1,4 +1,5 @@
 Copyright (c) 2009,2014 Google Inc. All rights reserved.
+Copyright (c) 2021 Pedro Albanese. All rights reserved.
 
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions are

cmd/uuid/main.go

@@ -0,0 +1,54 @@
+// Package main is the main package for the UUID generator application.
+package main
+
+import (
+	"bytes"
+	"flag"
+	"fmt"
+	"io"
+	"os"
+	"strings"
+	"time"
+
+	"github.com/google/uuid"
+)
+
+// parse is a command-line flag to parse the given UUID. ('-' for STDIN)
+var (
+	parse = flag.String("d", "", "Parse given UUID. ('-' for STDIN)")
+)
+
+func main() {
+	flag.Parse()
+	var lreader io.Reader
+
+	// If no UUID is given as input, generate a new UUID and print it.
+	if *parse == "" {
+		u, _ := uuid.NewUUID()
+		fmt.Printf("%s\n", u)
+	} else if *parse != "" { // If a UUID is provided as input, parse and process it.
+		if *parse == "-" { // If input is "-", read from STDIN.
+			lreader = os.Stdin
+		} else { // Otherwise, read from the provided input string.
+			lreader = strings.NewReader(*parse)
+		}
+
+		buf := new(bytes.Buffer)
+		buf.ReadFrom(lreader)
+		s := buf.String()
+		s = strings.TrimSuffix(s, "\n")
+
+		// Parse the UUID string to a UUID object.
+		uuid, _ := uuid.Parse(s)
+		fmt.Printf("UUID= %s\n", uuid)
+
+		// Get the timestamp information from the parsed UUID.
+		id := uuid
+		t := id.Time()
+		sec, nsec := t.UnixTime()
+		timeStamp := time.Unix(sec, nsec)
+
+		// Print the timestamp in a formatted date string.
+		fmt.Printf("DATE= %v \n", timeStamp.Format("2006-01-02 Mon 15:04:05.00000Z -0700"))
+	}
+}

go.mod

@@ -1 +1 @@
-module github.com/google/uuid
+module github.com/pedroalbanese/uuid