From a839b41ee4fcc91633293622dd171ca9d552b0d6 Mon Sep 17 00:00:00 2001
From: Janez Troha <dz0ny@ubuntu.si>
Date: Thu, 16 Apr 2020 14:40:17 +0200
Subject: [PATCH] Add support fo skipping files by date

---
 main.go | 21 +++++++++++++++++++--
 tar.go  | 12 ++++++++++--
 2 files changed, 29 insertions(+), 4 deletions(-)

diff --git a/main.go b/main.go
index ee5fa14..6703e71 100644
--- a/main.go
+++ b/main.go
@@ -2,9 +2,11 @@ package main
 
 import (
 	"os"
+	"time"
 
 	"github.com/woocart/targz/logger"
 	"github.com/woocart/targz/version"
+	"go.uber.org/zap"
 	kingpin "gopkg.in/alecthomas/kingpin.v2"
 )
 
@@ -14,14 +16,29 @@ var app = kingpin.New("targz", "Compress data to Tar using gzip compression.")
 var from = app.Arg("from", "Directory or file to compress").Required().ExistingFileOrDir()
 var to = app.Arg("to", "Where to write to [path or stdout]").Required().String()
 var exclude = app.Flag("exclude", "Exclude files matching PATTERN, a glob(3)-style wildcard pattern.").Strings()
+var afterString = app.Flag("afterDate", "Exclude files created before date (RFC3339).").String()
 
 func main() {
 	app.Author("dz0ny")
 	app.Version(version.String())
 	kingpin.MustParse(app.Parse(os.Args[1:]))
+	after := time.Unix(0, 0) // from start of counting
+	if *afterString != "" {
+		if *afterString == "now" {
+			after = time.Now()
+		} else {
+			afterParsed, err := time.Parse(time.RFC3339, *afterString)
+			if err != nil {
+				log.Fatal("Could not parse afterDate", err)
+			}
+			after = afterParsed
+		}
+
+		log.Infow("Only including files create or modified", zap.String("afterDate", after.Format(time.RFC3339)))
+	}
 
 	if *to == "stdout" {
-		err := Tar(*from, os.Stdout, *exclude)
+		err := Tar(*from, os.Stdout, *exclude, after)
 		if err != nil {
 			log.Fatal(err)
 		}
@@ -30,7 +47,7 @@ func main() {
 		if err != nil {
 			log.Fatal(err)
 		}
-		err = Tar(*from, f, *exclude)
+		err = Tar(*from, f, *exclude, after)
 		if err != nil {
 			log.Fatal(err)
 		}
diff --git a/tar.go b/tar.go
index 3f6d933..4b13835 100644
--- a/tar.go
+++ b/tar.go
@@ -9,6 +9,7 @@ import (
 	"path/filepath"
 	"regexp"
 	"strings"
+	"time"
 
 	"go.uber.org/zap"
 )
@@ -16,7 +17,7 @@ import (
 // Tar takes a source and variable writers and walks 'source' writing each file
 // found to the tar writer; the purpose for accepting multiple writers is to allow
 // for multiple outputs (for example a file, or md5 hash)
-func Tar(src string, writer io.Writer, excludes []string) error {
+func Tar(src string, writer io.Writer, excludes []string, after time.Time) error {
 
 	source, err := filepath.Abs(src)
 	if err != nil {
@@ -52,7 +53,7 @@ func Tar(src string, writer io.Writer, excludes []string) error {
 
 		for _, exclude := range excludes {
 			if matched, _ := regexp.MatchString(exclude, filePath); matched {
-				log.Infow("Skipped", zap.String("file", filePath))
+				log.Debugw("Skipped", zap.String("file", filePath))
 				return nil
 			}
 		}
@@ -66,6 +67,13 @@ func Tar(src string, writer io.Writer, excludes []string) error {
 			return err
 		}
 
+		// To use AccessTime or ChangeTime, specify the Format as PAX or GNU.
+		// To use sub-second resolution, specify the Format as PAX.
+		if header.ModTime.Before(after) {
+			log.Debugw("Skipped due modified-date", zap.String("file", filePath))
+			return nil
+		}
+
 		// update the name to correctly reflect the desired destination when untaring
 		header.Name = filePath
 		header.Gid = 0