64 lines
1.8 KiB
Go
64 lines
1.8 KiB
Go
package mkcw
|
|
|
|
import (
|
|
"crypto/rand"
|
|
"os"
|
|
"path/filepath"
|
|
"testing"
|
|
|
|
"github.com/stretchr/testify/require"
|
|
)
|
|
|
|
func TestReadWriteWorkloadConfig(t *testing.T) {
|
|
t.Parallel()
|
|
// Create a temporary file to stand in for a disk image.
|
|
temp := filepath.Join(t.TempDir(), "disk.img")
|
|
f, err := os.OpenFile(temp, os.O_CREATE|os.O_RDWR, 0o600)
|
|
require.NoError(t, err)
|
|
err = f.Truncate(0x1000000)
|
|
require.NoError(t, err)
|
|
defer f.Close()
|
|
|
|
// Generate a random "encoded workload config".
|
|
workloadConfig := make([]byte, 0x100)
|
|
n, err := rand.Read(workloadConfig)
|
|
require.NoError(t, err)
|
|
require.Equal(t, len(workloadConfig), n)
|
|
|
|
// Read the size of our temporary file.
|
|
st, err := f.Stat()
|
|
require.NoError(t, err)
|
|
originalSize := st.Size()
|
|
|
|
// Should get an error, since there's no workloadConfig in there to read.
|
|
_, err = ReadWorkloadConfigFromImage(f.Name())
|
|
require.Error(t, err)
|
|
|
|
// File should grow, even though we looked for an old config to overwrite.
|
|
err = WriteWorkloadConfigToImage(f, workloadConfig, true)
|
|
require.NoError(t, err)
|
|
st, err = f.Stat()
|
|
require.NoError(t, err)
|
|
require.Greater(t, st.Size(), originalSize)
|
|
originalSize = st.Size()
|
|
|
|
// File shouldn't grow, even overwriting the config with a slightly larger one.
|
|
err = WriteWorkloadConfigToImage(f, append([]byte("slightly longer"), workloadConfig...), true)
|
|
require.NoError(t, err)
|
|
st, err = f.Stat()
|
|
require.NoError(t, err)
|
|
require.Equal(t, originalSize, st.Size())
|
|
originalSize = st.Size()
|
|
|
|
// File should grow if we're not trying to replace an old one config with a new one.
|
|
err = WriteWorkloadConfigToImage(f, []byte("{\"comment\":\"quite a bit shorter\"}"), false)
|
|
require.NoError(t, err)
|
|
st, err = f.Stat()
|
|
require.NoError(t, err)
|
|
require.Greater(t, st.Size(), originalSize)
|
|
|
|
// Should read successfully.
|
|
_, err = ReadWorkloadConfigFromImage(f.Name())
|
|
require.NoError(t, err)
|
|
}
|