TRA-3234 Fetch command (#54)

* preparation to fetch command

* get har as zip from server

* no message

* no message

cli/cmd/fetchRunner.go

@@ -0,0 +1,92 @@
+package cmd
+
+import (
+	"archive/zip"
+	"bytes"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"log"
+	"net/http"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+func RunMizuFetch(fetch *MizuFetchOptions) {
+	resp, err :=  http.Get(fmt.Sprintf("http://localhost:8899/api/har?limit=%v", fetch.Limit))
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	defer func() { _ = resp.Body.Close() }()
+
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	zipReader, err := zip.NewReader(bytes.NewReader(body), int64(len(body)))
+	if err != nil {
+		log.Fatal(err)
+	}
+	_ = Unzip(zipReader, fetch.Directory)
+
+}
+
+func Unzip(reader *zip.Reader, dest string) error {
+	dest, _ = filepath.Abs(dest)
+	_ = os.MkdirAll(dest, os.ModePerm)
+
+	// Closure to address file descriptors issue with all the deferred .Close() methods
+	extractAndWriteFile := func(f *zip.File) error {
+		rc, err := f.Open()
+		if err != nil {
+			return err
+		}
+		defer func() {
+			if err := rc.Close(); err != nil {
+				panic(err)
+			}
+		}()
+
+		path := filepath.Join(dest, f.Name)
+
+		// Check for ZipSlip (Directory traversal)
+		if !strings.HasPrefix(path, filepath.Clean(dest) + string(os.PathSeparator)) {
+			return fmt.Errorf("illegal file path: %s", path)
+		}
+
+		if f.FileInfo().IsDir() {
+			_ = os.MkdirAll(path, f.Mode())
+		} else {
+			_ = os.MkdirAll(filepath.Dir(path), f.Mode())
+			f, err := os.OpenFile(path, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, f.Mode())
+			if err != nil {
+				return err
+			}
+			defer func() {
+				if err := f.Close(); err != nil {
+					panic(err)
+				}
+			}()
+
+			_, err = io.Copy(f, rc)
+			if err != nil {
+				return err
+			}
+		}
+		return nil
+	}
+
+	for _, f := range reader.File {
+		err := extractAndWriteFile(f)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+