fix(#77): stdin redirect (#78)

README.md

@@ -70,7 +70,7 @@ jlv << EOF
 EOF
 
 kubectl logs pod/POD_NAME -f | jlv
-docker logs 000000000000 | jlv
+docker logs -f 000000000000 2>&1 | jlv
 ```
 
 ### Hotkeys

cmd/jlv/main.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"flag"
 	"fmt"
+	"io/fs"
 	"os"
 	"path"
 
@@ -42,7 +43,7 @@ func main() {
 
 	switch flag.NArg() {
 	case 0:
-		sourceInput, err = getStdinSource(cfg)
+		sourceInput, err = getStdinSource(cfg, os.Stdin)
 		if err != nil {
 			fatalf("Stdin: %s\n", err)
 		}
@@ -60,17 +61,17 @@ func main() {
 	}
 }
 
-func getStdinSource(cfg *config.Config) (source.Input, error) {
-	stat, err := os.Stdin.Stat()
+func getStdinSource(cfg *config.Config, defaultInput fs.File) (source.Input, error) {
+	stat, err := defaultInput.Stat()
 	if err != nil {
 		return nil, fmt.Errorf("stat: %w", err)
 	}
 
-	if stat.Mode()&os.ModeNamedPipe == 0 {
+	if stat.Mode()&os.ModeCharDevice != 0 {
 		return readerinput.New(bytes.NewReader(nil), cfg.StdinReadTimeout), nil
 	}
 
-	return readerinput.New(os.Stdin, cfg.StdinReadTimeout), nil
+	return readerinput.New(defaultInput, cfg.StdinReadTimeout), nil
 }
 
 func fatalf(message string, args ...any) {

cmd/jlv/main_test.go

@@ -0,0 +1,106 @@
+package main
+
+import (
+	"bytes"
+	"context"
+	"errors"
+	"io"
+	"io/fs"
+	"os"
+	"testing"
+
+	"github.com/hedhyw/json-log-viewer/internal/pkg/config"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestGetStdinSource(t *testing.T) {
+	t.Parallel()
+
+	ctx := context.Background()
+
+	t.Run("ModeNamedPipe", func(t *testing.T) {
+		t.Parallel()
+
+		content := t.Name() + "\n"
+
+		file := fakeFile{
+			Reader: bytes.NewReader([]byte(content)),
+			StatFileInfo: fakeFileInfo{
+				FileMode: os.ModeNamedPipe,
+			},
+		}
+
+		input, err := getStdinSource(config.GetDefaultConfig(), file)
+		require.NoError(t, err)
+
+		readCloser, err := input.ReadCloser(ctx)
+		require.NoError(t, err)
+
+		t.Cleanup(func() { assert.NoError(t, readCloser.Close()) })
+
+		data, err := io.ReadAll(readCloser)
+		require.NoError(t, err)
+		assert.Equal(t, content, string(data))
+	})
+
+	t.Run("ModeCharDevice", func(t *testing.T) {
+		t.Parallel()
+
+		file := fakeFile{
+			Reader: bytes.NewReader([]byte(t.Name() + "\n")),
+			StatFileInfo: fakeFileInfo{
+				FileMode: os.ModeCharDevice,
+			},
+		}
+
+		input, err := getStdinSource(config.GetDefaultConfig(), file)
+		require.NoError(t, err)
+
+		readCloser, err := input.ReadCloser(ctx)
+		require.NoError(t, err)
+
+		t.Cleanup(func() { assert.NoError(t, readCloser.Close()) })
+
+		data, err := io.ReadAll(readCloser)
+		require.NoError(t, err)
+		assert.Empty(t, data)
+	})
+
+	t.Run("Stat_error", func(t *testing.T) {
+		t.Parallel()
+
+		// nolint: err113 // Test.
+		errStat := errors.New(t.Name())
+
+		file := fakeFile{ErrStat: errStat}
+
+		_, err := getStdinSource(config.GetDefaultConfig(), file)
+		require.Error(t, err)
+		require.ErrorIs(t, err, errStat)
+	})
+}
+
+type fakeFile struct {
+	io.Closer
+	io.Reader
+
+	StatFileInfo os.FileInfo
+	ErrStat      error
+}
+
+// Stat implements fs.File.
+func (f fakeFile) Stat() (os.FileInfo, error) {
+	return f.StatFileInfo, f.ErrStat
+}
+
+type fakeFileInfo struct {
+	fs.FileInfo
+	FileMode fs.FileMode
+}
+
+// Mode implements fs.FileInfo.
+func (f fakeFileInfo) Mode() fs.FileMode {
+	return f.FileMode
+}