3 files changed, 171 insertions, 0 deletions
diff --git a/fileop/fileop.go b/fileop/fileop.go
new file mode 100644
index 0000000..d08cb82
--- /dev/null
+++ b/fileop/fileop.go
@@ -0,0 +1,66 @@
+package fileop
+
+import (
+	"crypto/sha256"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+)
+
+func WalkFolder(folder string) <-chan string {
+	c := make(chan string)
+
+	go func(folder string, c chan string) {
+		filepath.Walk(folder, func(path string, info os.FileInfo, err error) error {
+			file, _ := os.Open(path)
+			defer file.Close()
+			fileInfo, _ := file.Stat()
+			if !fileInfo.IsDir() {
+				c <- path
+			}
+			return nil
+		})
+		close(c)
+
+	}(folder, c)
+
+	return c
+}
+
+func CalculateSHA256(file string) (string, error) {
+	f, err := os.Open(file)
+	if err != nil {
+		return "", err
+	}
+	defer f.Close()
+
+	h := sha256.New()
+	if _, err := io.Copy(h, f); err != nil {
+		return "", err
+	}
+
+	shaString := fmt.Sprintf("%x", h.Sum(nil))
+
+	return shaString, nil
+}
+
+type MoveCommand struct {
+	Source      string
+	Destination string
+}
+
+func Move() chan<- *MoveCommand {
+	c := make(chan *MoveCommand)
+	go func(chan *MoveCommand) {
+		for cmd := range c {
+			// TODO: add error handling
+			err := os.Rename(cmd.Source, cmd.Destination)
+			if err != nil {
+				fmt.Println(err.Error())
+			}
+		}
+	}(c)
+
+	return c
+}
diff --git a/fileop/fileop_test.go b/fileop/fileop_test.go
new file mode 100644
index 0000000..f2ab864
--- /dev/null
+++ b/fileop/fileop_test.go
@@ -0,0 +1,97 @@
+package fileop
+
+import (
+	"fmt"
+	"math/rand"
+	"os"
+	"testing"
+	"time"
+)
+
+func init() {
+	rand.Seed(time.Now().UnixNano())
+}
+
+func RandomString(n int) string {
+	var letters = []rune("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789")
+	s := make([]rune, n)
+	for i := range s {
+		s[i] = letters[rand.Intn(len(letters))]
+	}
+	return string(s)
+}
+
+func createFolder() (tmp string) {
+	tmp = fmt.Sprintf("/tmp/%s", RandomString(10))
+
+	err := os.Mkdir(tmp, 0755)
+
+	if err != nil {
+		fmt.Println(err.Error())
+	}
+
+	return
+}
+
+func appendEmptyFile(path string) (fullPath string) {
+	fullPath = fmt.Sprintf("%s/%s", path, RandomString(10))
+	os.OpenFile(fullPath, os.O_RDONLY|os.O_CREATE, 0666)
+
+	return
+}
+
+func createEmptyFile(path string) {
+	os.OpenFile(path, os.O_RDONLY|os.O_CREATE, 0666)
+}
+
+func createTmpFile() (fullPath string) {
+	path := createFolder()
+	fullPath = appendEmptyFile(path)
+	return
+}
+
+func TestMove(t *testing.T) {
+	src := createTmpFile()
+	dest := fmt.Sprintf("/tmp/%s", RandomString(10))
+
+	c := Move()
+
+	c <- &MoveCommand{Source: src, Destination: dest}
+	close(c)
+
+	if _, err := os.Stat(dest); err != nil {
+		t.Errorf("File %s not moved to %s", src, dest)
+	}
+
+}
+
+func TestWalk(t *testing.T) {
+	fileCount := 1000
+	folder := createFolder()
+	files := map[string]struct{}{}
+	walkedFiles := map[string]struct{}{}
+
+	for i := 0; i < fileCount; i++ {
+		files[appendEmptyFile(folder)] = struct{}{}
+	}
+
+	c := WalkFolder(folder)
+	for file := range c {
+		walkedFiles[file] = struct{}{}
+	}
+
+	for k := range files {
+		_, ok := walkedFiles[k]
+		if !ok {
+			t.Errorf("File %s was not walked", k)
+		}
+	}
+}
+
+func TestCalculateSHA256(t *testing.T) {
+	sh256, _ := CalculateSHA256("test_file.txt")
+
+	if sh256 != "027cc886f9b8c866f932ef8b8da9a32f0857ef8e16ec98dd2797021b34623b88" {
+		t.Errorf("Wrong sh256 hash, given %s", sh256)
+	}
+}
diff --git a/fileop/test_file.txt b/fileop/test_file.txt
new file mode 100644
index 0000000..db88e33
--- /dev/null
+++ b/fileop/test_file.txt
@@ -0,0 +1,8 @@
+Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod
+tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At
+vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd
+gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum
+dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor
+invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero
+eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no
+sea takimata sanctus est Lorem ipsum dolor sit amet.