Add unit test for cio

Signed-off-by: Daniel Nephin <dnephin@gmail.com>

cio/io_test.go

@@ -0,0 +1,132 @@
+// +build !windows
+
+package cio
+
+import (
+	"bytes"
+	"context"
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"syscall"
+	"testing"
+
+	"github.com/containerd/fifo"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func assertHasPrefix(t *testing.T, s, prefix string) {
+	t.Helper()
+	if !strings.HasPrefix(s, prefix) {
+		t.Fatalf("expected %s to start with %s", s, prefix)
+	}
+}
+
+func TestNewFIFOSetInDir(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		t.Skip("NewFIFOSetInDir has different behaviour on windows")
+	}
+
+	root, err := ioutil.TempDir("", "test-new-fifo-set")
+	require.NoError(t, err)
+	defer os.RemoveAll(root)
+
+	fifos, err := NewFIFOSetInDir(root, "theid", true)
+	require.NoError(t, err)
+
+	assertHasPrefix(t, fifos.Stdin, root)
+	assertHasPrefix(t, fifos.Stdout, root)
+	assertHasPrefix(t, fifos.Stderr, root)
+	assert.Equal(t, "theid-stdin", filepath.Base(fifos.Stdin))
+	assert.Equal(t, "theid-stdout", filepath.Base(fifos.Stdout))
+	assert.Equal(t, "theid-stderr", filepath.Base(fifos.Stderr))
+	assert.Equal(t, true, fifos.Terminal)
+
+	files, err := ioutil.ReadDir(root)
+	require.NoError(t, err)
+	assert.Len(t, files, 1)
+
+	require.NoError(t, fifos.Close())
+	files, err = ioutil.ReadDir(root)
+	require.NoError(t, err)
+	assert.Len(t, files, 0)
+}
+
+func TestNewAttach(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		t.Skip("setupFIFOProducers not yet implemented on windows")
+	}
+	var (
+		expectedStdin  = "this is the stdin"
+		expectedStdout = "this is the stdout"
+		expectedStderr = "this is the stderr"
+		stdin          = bytes.NewBufferString(expectedStdin)
+		stdout         = new(bytes.Buffer)
+		stderr         = new(bytes.Buffer)
+	)
+
+	withBytesBuffers := func(streams *Streams) {
+		*streams = Streams{Stdin: stdin, Stdout: stdout, Stderr: stderr}
+	}
+	attacher := NewAttach(withBytesBuffers)
+
+	fifos, err := NewFIFOSetInDir("", "theid", false)
+	require.NoError(t, err)
+
+	io, err := attacher(fifos)
+	require.NoError(t, err)
+	defer io.Close()
+
+	producers := setupFIFOProducers(t, io.Config())
+	initProducers(t, producers, expectedStdout, expectedStderr)
+
+	actualStdin, err := ioutil.ReadAll(producers.Stdin)
+	require.NoError(t, err)
+
+	io.Cancel()
+	io.Wait()
+	assert.NoError(t, io.Close())
+
+	assert.Equal(t, expectedStdout, stdout.String())
+	assert.Equal(t, expectedStderr, stderr.String())
+	assert.Equal(t, expectedStdin, string(actualStdin))
+}
+
+type producers struct {
+	Stdin  io.ReadCloser
+	Stdout io.WriteCloser
+	Stderr io.WriteCloser
+}
+
+func setupFIFOProducers(t *testing.T, fifos Config) producers {
+	var (
+		err   error
+		pipes producers
+		ctx   = context.Background()
+	)
+
+	pipes.Stdin, err = fifo.OpenFifo(ctx, fifos.Stdin, syscall.O_RDONLY, 0)
+	require.NoError(t, err)
+
+	pipes.Stdout, err = fifo.OpenFifo(ctx, fifos.Stdout, syscall.O_WRONLY, 0)
+	require.NoError(t, err)
+
+	pipes.Stderr, err = fifo.OpenFifo(ctx, fifos.Stderr, syscall.O_WRONLY, 0)
+	require.NoError(t, err)
+
+	return pipes
+}
+
+func initProducers(t *testing.T, producers producers, stdout, stderr string) {
+	_, err := producers.Stdout.Write([]byte(stdout))
+	require.NoError(t, err)
+	require.NoError(t, producers.Stdout.Close())
+
+	_, err = producers.Stderr.Write([]byte(stderr))
+	require.NoError(t, err)
+	require.NoError(t, producers.Stderr.Close())
+}