feat(util): add util function implements

with #22357426

Signed-off-by: Cloudstriff <chenjiongwendao@qq.com>

blobstore/util/util.go

@@ -0,0 +1,77 @@
+// Copyright 2023 The Cuber Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+// implied. See the License for the specific language governing
+// permissions and limitations under the License.
+
+package util
+
+import (
+	"errors"
+	"net"
+	"os"
+	"unsafe"
+
+	"github.com/google/uuid"
+)
+
+// GenTmpPath create a temporary path
+func GenTmpPath() (string, error) {
+	id := uuid.NewString()
+	path := os.TempDir() + "/" + id
+	if err := os.RemoveAll(path); err != nil {
+		return "", err
+	}
+	if err := os.MkdirAll(path, 0o755); err != nil {
+		return "", err
+	}
+	return path, nil
+}
+
+func StringToBytes(s string) []byte {
+	return unsafe.Slice(unsafe.StringData(s), len(s))
+}
+
+func BytesToString(b []byte) string {
+	return unsafe.String(unsafe.SliceData(b), len(b))
+}
+
+func GetLocalIP() (string, error) {
+	addresses, err := net.InterfaceAddrs()
+	if err != nil {
+		return "", err
+	}
+
+	for _, address := range addresses {
+		if ipnet, ok := address.(*net.IPNet); ok && !ipnet.IP.IsLoopback() {
+			if ipnet.IP.To4() != nil {
+				return ipnet.IP.String(), nil
+			}
+		}
+	}
+
+	return "", errors.New("can not find the local ip address")
+}
+
+func GenUnusedPort() int {
+	addr, err := net.ResolveTCPAddr("tcp", "localhost:0")
+	if err != nil {
+		return 0
+	}
+
+	l, err := net.ListenTCP("tcp", addr)
+	if err != nil {
+		return 0
+	}
+	defer l.Close()
+
+	return l.Addr().(*net.TCPAddr).Port
+}

blobstore/util/util_test.go

@@ -0,0 +1,41 @@
+// Copyright 2023 The Cuber Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+// implied. See the License for the specific language governing
+// permissions and limitations under the License.
+
+package util
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestGenTmpPath(t *testing.T) {
+	path, err := GenTmpPath()
+	require.NoError(t, err)
+	require.NotEqual(t, "", path)
+}
+
+func TestStringsToBytes(t *testing.T) {
+	str := "test"
+	b := StringToBytes(str)
+	require.Equal(t, str, string(b))
+	require.Equal(t, 0, len(StringToBytes("")))
+}
+
+func TestBytesToString(t *testing.T) {
+	b := []byte("test")
+	str := BytesToString(b)
+	require.Equal(t, str, string(b))
+	require.Equal(t, "", BytesToString(nil))
+}