moby/pkg/ioutils/fswriters_test.go
Derek McGowan c37bd10f8c Update layer store to sync transaction files before committing
Fixes case where shutdown occurs before content is synced to disked
on layer creation. This case can leave the layer store in an bad
state and require manual recovery. This change ensures all files
are synced to disk before a layer is committed. Any shutdown that
occurs will only cause the layer to not show up but will allow it to
be repulled or recreated without error.

Added generic io logic to ioutils package to abstract it out of
the layer store package.


Signed-off-by: Derek McGowan <derek@mcgstyle.net>
2016-08-09 11:55:17 -07:00

132 lines
3.4 KiB
Go

package ioutils
import (
"bytes"
"io/ioutil"
"os"
"path/filepath"
"runtime"
"testing"
)
var (
testMode os.FileMode = 0640
)
func init() {
// Windows does not support full Linux file mode
if runtime.GOOS == "windows" {
testMode = 0666
}
}
func TestAtomicWriteToFile(t *testing.T) {
tmpDir, err := ioutil.TempDir("", "atomic-writers-test")
if err != nil {
t.Fatalf("Error when creating temporary directory: %s", err)
}
defer os.RemoveAll(tmpDir)
expected := []byte("barbaz")
if err := AtomicWriteFile(filepath.Join(tmpDir, "foo"), expected, testMode); err != nil {
t.Fatalf("Error writing to file: %v", err)
}
actual, err := ioutil.ReadFile(filepath.Join(tmpDir, "foo"))
if err != nil {
t.Fatalf("Error reading from file: %v", err)
}
if bytes.Compare(actual, expected) != 0 {
t.Fatalf("Data mismatch, expected %q, got %q", expected, actual)
}
st, err := os.Stat(filepath.Join(tmpDir, "foo"))
if err != nil {
t.Fatalf("Error statting file: %v", err)
}
if expected := os.FileMode(testMode); st.Mode() != expected {
t.Fatalf("Mode mismatched, expected %o, got %o", expected, st.Mode())
}
}
func TestAtomicWriteSetCommit(t *testing.T) {
tmpDir, err := ioutil.TempDir("", "atomic-writerset-test")
if err != nil {
t.Fatalf("Error when creating temporary directory: %s", err)
}
defer os.RemoveAll(tmpDir)
if err := os.Mkdir(filepath.Join(tmpDir, "tmp"), 0700); err != nil {
t.Fatalf("Error creating tmp directory: %s", err)
}
targetDir := filepath.Join(tmpDir, "target")
ws, err := NewAtomicWriteSet(filepath.Join(tmpDir, "tmp"))
if err != nil {
t.Fatalf("Error creating atomic write set: %s", err)
}
expected := []byte("barbaz")
if err := ws.WriteFile("foo", expected, testMode); err != nil {
t.Fatalf("Error writing to file: %v", err)
}
if _, err := ioutil.ReadFile(filepath.Join(targetDir, "foo")); err == nil {
t.Fatalf("Expected error reading file where should not exist")
}
if err := ws.Commit(targetDir); err != nil {
t.Fatalf("Error committing file: %s", err)
}
actual, err := ioutil.ReadFile(filepath.Join(targetDir, "foo"))
if err != nil {
t.Fatalf("Error reading from file: %v", err)
}
if bytes.Compare(actual, expected) != 0 {
t.Fatalf("Data mismatch, expected %q, got %q", expected, actual)
}
st, err := os.Stat(filepath.Join(targetDir, "foo"))
if err != nil {
t.Fatalf("Error statting file: %v", err)
}
if expected := os.FileMode(testMode); st.Mode() != expected {
t.Fatalf("Mode mismatched, expected %o, got %o", expected, st.Mode())
}
}
func TestAtomicWriteSetCancel(t *testing.T) {
tmpDir, err := ioutil.TempDir("", "atomic-writerset-test")
if err != nil {
t.Fatalf("Error when creating temporary directory: %s", err)
}
defer os.RemoveAll(tmpDir)
if err := os.Mkdir(filepath.Join(tmpDir, "tmp"), 0700); err != nil {
t.Fatalf("Error creating tmp directory: %s", err)
}
ws, err := NewAtomicWriteSet(filepath.Join(tmpDir, "tmp"))
if err != nil {
t.Fatalf("Error creating atomic write set: %s", err)
}
expected := []byte("barbaz")
if err := ws.WriteFile("foo", expected, testMode); err != nil {
t.Fatalf("Error writing to file: %v", err)
}
if err := ws.Cancel(); err != nil {
t.Fatalf("Error committing file: %s", err)
}
if _, err := ioutil.ReadFile(filepath.Join(tmpDir, "target", "foo")); err == nil {
t.Fatalf("Expected error reading file where should not exist")
} else if !os.IsNotExist(err) {
t.Fatalf("Unexpected error reading file: %s", err)
}
}