Import source: handler/fs/path

Import the existing local project snapshot. This commit organizes existing files; it does not represent newly developed functionality.

handler/fs/path.go

@@ -0,0 +1,94 @@
+package fs
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"io/fs"
+	"os"
+	"path"
+	"path/filepath"
+)
+
+var (
+	// ErrNoCurrentDir returned on creating the content file before the current
+	// directory was created.
+	ErrNoCurrentDir = errors.New("current dir was not created")
+
+	// ErrInvalidDest returned when provided save path is not a valid directory.
+	ErrInvalidDest = errors.New("invalid destination path")
+)
+
+type PathResolver struct {
+	// Dest contains a base directory for all folders that will be created.
+	// It should be a valid absolute or relative path and must already exist.
+	Dest string
+
+	absDest     string
+	currentDest string
+}
+
+// NewPathResolver returns new *PathResolver along with resolving provided dest
+// value. If an incorrect dest value is provided an error will be returned.
+func NewPathResolver(dest string) (*PathResolver, error) {
+	absDest, err := filepath.Abs(dest)
+	if err != nil {
+		return nil, ErrInvalidDest
+	}
+
+	stat, err := os.Stat(absDest)
+	if err != nil || !stat.IsDir() {
+		return nil, ErrInvalidDest
+	}
+
+	return &PathResolver{
+		Dest:    dest,
+		absDest: absDest,
+	}, nil
+}
+
+// CreateFolder creates a new dir with the provided name within PathResolver.Dest dir.
+// Created dir will be marked as current dir. If dir already exists the creation
+// step will be skipped.
+func (p *PathResolver) CreateFolder(name string) error {
+	err := os.Chdir(p.absDest)
+	if err != nil {
+		return fmt.Errorf("cannot resolve path for folder %s: %w", name, err)
+	}
+
+	p.currentDest = path.Join(p.absDest, name)
+
+	err = os.Mkdir(name, fs.ModePerm)
+	if err != nil {
+		if os.IsExist(err) {
+			return nil
+		}
+		return fmt.Errorf("cannot create folder %s: %w", p.currentDest, err)
+	}
+
+	return nil
+}
+
+// CreateFile creates a new file with the corresponding name and returns its
+// io.WriteCloser. If FSResolver.currentDest wasn't created before, then an error
+// will be returned.
+func (p *PathResolver) CreateFile(name string) (io.WriteCloser, error) {
+	if p.currentDest == "" {
+		return nil, ErrNoCurrentDir
+	}
+
+	filePath := path.Join(p.currentDest, name)
+
+	f, err := os.Create(filePath)
+	if err != nil {
+		return nil, fmt.Errorf("cannot create file %s: %w", filePath, err)
+	}
+
+	return f, nil
+}
+
+// Remove removes file or dir by its name. If the provided path wasn't found the
+// deletion step will be skipped.
+func (p *PathResolver) Remove(name string) {
+	_ = os.Remove(name)
+}

handler/fs/path_test.go

@@ -0,0 +1,82 @@
+//go:build unit
+// +build unit
+
+package fs_test
+
+import (
+	"os"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"reactor-crw/handler/fs"
+)
+
+func TestNewPathResolver(t *testing.T) {
+	paths := []struct {
+		name        string
+		msg         string
+		errExpected bool
+	}{
+		{" ", "Expected an error during resolving empty path", true},
+		{"invalid_path", "Expected an error during resolving non-existent dir", true},
+		{os.TempDir(), "Wasn't expected an error", false},
+	}
+
+	for _, path := range paths {
+		_, err := fs.NewPathResolver(path.name)
+		if path.errExpected {
+			require.Errorf(t, err, path.msg)
+		}
+
+		if !path.errExpected {
+			require.NoError(t, err, path.msg)
+		}
+	}
+}
+
+func TestPathResolver_CreateFolder(t *testing.T) {
+	p, _ := fs.NewPathResolver(os.TempDir())
+
+	folders := []struct {
+		name        string
+		errExpected bool
+	}{
+		{name: "test"},
+		{name: "_123_test"},
+		{name: "109483___"},
+	}
+
+	for _, folder := range folders {
+		err := p.CreateFolder(folder.name)
+		if !folder.errExpected {
+			require.NoError(t, err, "Wasn't expected an error during creating %s", folder.name)
+		}
+
+		if folder.errExpected {
+			require.Error(t, err, "Expected an error during creating %s", folder.name)
+		}
+
+		p.Remove(folder.name)
+	}
+
+	p = &fs.PathResolver{}
+	err := p.CreateFolder("test")
+	require.Error(t, err, "Expected an error during creating folder")
+}
+
+func TestPathResolver_CreateFile(t *testing.T) {
+	p, _ := fs.NewPathResolver(os.TempDir())
+	_, err := p.CreateFile("filename")
+	require.Error(t, err, "Expected an error during file. Folder wasn't created yet.")
+
+	_ = p.CreateFolder("test")
+
+	_, err = p.CreateFile("filename")
+	require.NoError(t, err, "Wasn't expected an error during creating filename")
+
+	filePath := "./test/filename"
+	_, err = os.Stat(filePath)
+	require.NoError(t, err, "File %s wasn't created", filePath)
+
+	p.Remove(filePath)
+}