pkg/shaman/checkout/checkout_test.go

@@ -44,18 +44,31 @@ func TestCheckout(t *testing.T) {
 	assert.FileExists(t, filepath.Join(coPath, "httpstuff.py"))
 	assert.FileExists(t, filepath.Join(coPath, "много ликова.py"))
 
-	storePath := manager.fileStore.StoragePath()
-	assertLinksTo(t, filepath.Join(coPath, "subdir", "replacer.py"),
-		filepath.Join(storePath, "59", "0c148428d5c35fab3ebad2f3365bb469ab9c531b60831f3e826c472027a0b9", "3367.blob"))
-	assertLinksTo(t, filepath.Join(coPath, "feed.py"),
-		filepath.Join(storePath, "80", "b749c27b2fef7255e7e7b3c2029b03b31299c75ff1f1c72732081c70a713a3", "7488.blob"))
-	assertLinksTo(t, filepath.Join(coPath, "httpstuff.py"),
-		filepath.Join(storePath, "91", "4853599dd2c351ab7b82b219aae6e527e51518a667f0ff32244b0c94c75688", "486.blob"))
-	assertLinksTo(t, filepath.Join(coPath, "много ликова.py"),
-		filepath.Join(storePath, "d6", "fc7289b5196cc96748ea72f882a22c39b8833b457fe854ef4c03a01f5db0d3", "7217.blob"))
+	storePath, err := filepath.Rel(
+		manager.checkoutBasePath,
+		manager.fileStore.StoragePath(),
+	)
+	require.NoError(t, err)
+	assertLinksTo(t,
+		// Two extra '..' for 'á hausinn á þér/subdir'.
+		filepath.Join("..", "..", storePath, "59", "0c148428d5c35fab3ebad2f3365bb469ab9c531b60831f3e826c472027a0b9", "3367.blob"),
+		filepath.Join(coPath, "subdir", "replacer.py"),
+	)
+	assertLinksTo(t,
+		filepath.Join("..", storePath, "80", "b749c27b2fef7255e7e7b3c2029b03b31299c75ff1f1c72732081c70a713a3", "7488.blob"),
+		filepath.Join(coPath, "feed.py"),
+	)
+	assertLinksTo(t,
+		filepath.Join("..", storePath, "91", "4853599dd2c351ab7b82b219aae6e527e51518a667f0ff32244b0c94c75688", "486.blob"),
+		filepath.Join(coPath, "httpstuff.py"),
+	)
+	assertLinksTo(t,
+		filepath.Join("..", storePath, "d6", "fc7289b5196cc96748ea72f882a22c39b8833b457fe854ef4c03a01f5db0d3", "7217.blob"),
+		filepath.Join(coPath, "много ликова.py"),
+	)
 }
 
-func assertLinksTo(t *testing.T, linkPath, expectedTarget string) {
+func assertLinksTo(t *testing.T, expectedTarget, linkPath string) {
 	actualTarget, err := os.Readlink(linkPath)
 	require.NoError(t, err)
 	assert.Equal(t, expectedTarget, actualTarget)

pkg/shaman/checkout/manager.go

@@ -202,22 +202,46 @@ func (m *Manager) EraseCheckout(checkoutID string) error {
 // It does *not* do any validation of the validity of the paths!
 func (m *Manager) SymlinkToCheckout(blobPath, checkoutPath, symlinkRelativePath string) error {
 	symlinkPath := filepath.Join(checkoutPath, symlinkRelativePath)
-	logger := log.With().
-		Str("blobPath", blobPath).
-		Str("symlinkPath", symlinkPath).
-		Logger()
+	logger := log.With().Str("symlinkPath", symlinkPath).Logger()
 
-	blobPath, err := filepath.Abs(blobPath)
+	blobAbsolute, err := filepath.Abs(blobPath)
 	if err != nil {
-		logger.Error().Err(err).Msg("shaman: unable to make blobPath absolute")
+		logger.Error().
+			Str("blobPath", blobPath).
+			Err(err).Msg("shaman: unable to make blobPath absolute")
 		return err
 	}
+	if blobAbsolute != blobPath {
+		logger.Trace().
+			Str("input", blobPath).
+			Str("absolute", blobAbsolute).
+			Msg("shaman: made blobpath absolute")
+	}
 
+	// Try and make blobAbsolute relative to the symlink target directory, so that
+	// mounting the symlinked storage at a different prefix works as well.
+	symlinkDir := filepath.Dir(symlinkPath)
+	blobRelativeToCheckout, err := filepath.Rel(symlinkDir, blobAbsolute)
+	if err != nil {
+		logger.Warn().
+			Str("blobPath", blobAbsolute).
+			AnErr("cause", err).
+			Msg("shaman: unable to make blobPath relative, will use absolute path")
+		blobRelativeToCheckout = blobAbsolute
+	}
+
+	logger.Trace().
+		Str("absolute", blobAbsolute).
+		Str("relative", blobRelativeToCheckout).
+		Str("symlinkDir", symlinkDir).
+		Msg("shaman: made blobpath relative")
+
+	logger = logger.With().Str("blobPath", blobRelativeToCheckout).Logger()
 	logger.Debug().Msg("shaman: creating symlink")
 
 	// This is expected to fail sometimes, because we don't create parent directories yet.
 	// We only create those when we get a failure from symlinking.
-	err = os.Symlink(blobPath, symlinkPath)
+	err = os.Symlink(blobRelativeToCheckout, symlinkPath)
 	switch {
 	case err == nil:
 		return nil
@@ -232,7 +256,7 @@ func (m *Manager) SymlinkToCheckout(blobPath, checkoutPath, symlinkRelativePath
 				Msg("shaman: unable to create symlink as it already exists, but also it cannot be read")
 			return err
 		}
-		if linkTarget != blobPath {
+		if linkTarget != blobRelativeToCheckout {
 			logger.Error().
 				AnErr("symlinkError", err).
 				Str("alreadyLinkedFrom", linkTarget).
@@ -251,7 +275,7 @@ func (m *Manager) SymlinkToCheckout(blobPath, checkoutPath, symlinkRelativePath
 			logger.Error().Err(err).Msg("shaman: unable to create parent directory")
 			return err
 		}
-		if err := os.Symlink(blobPath, symlinkPath); err != nil {
+		if err := os.Symlink(blobRelativeToCheckout, symlinkPath); err != nil {
 			logger.Error().Err(err).Msg("shaman: unable to create symlink, after creating parent directory")
 			return err
 		}
@@ -263,7 +287,7 @@ func (m *Manager) SymlinkToCheckout(blobPath, checkoutPath, symlinkRelativePath
 	// Change the modification time of the blob to mark it as 'referenced' just now.
 	m.wg.Add(1)
 	go func() {
-		if err := touchFile(blobPath); err != nil {
+		if err := touchFile(blobAbsolute); err != nil {
 			logger.Warn().Err(err).Msg("shaman: unable to touch blob path")
 		}
 		m.wg.Done()

pkg/shaman/checkout/manager_test.go

@@ -59,7 +59,7 @@ func TestSymlinkToCheckout(t *testing.T) {
 	defer cleanup()
 
 	// Fake an older file.
-	blobPath := filepath.Join(manager.checkoutBasePath, "jemoeder.blob")
+	blobPath := filepath.Join(manager.fileStore.StoragePath(), "opjehoofd.blob")
 	err := os.WriteFile(blobPath, []byte("op je hoofd"), 0600)
 	require.NoError(t, err)
 
@@ -67,14 +67,14 @@ func TestSymlinkToCheckout(t *testing.T) {
 	err = os.Chtimes(blobPath, wayBackWhen, wayBackWhen)
 	require.NoError(t, err)
 
-	symlinkRelativePath := "path/to/jemoeder.txt"
+	symlinkRelativePath := "path/to/opjehoofd.txt"
 	err = manager.SymlinkToCheckout(blobPath, manager.checkoutBasePath, symlinkRelativePath)
 	require.NoError(t, err)
 
 	err = manager.SymlinkToCheckout(blobPath, manager.checkoutBasePath, symlinkRelativePath)
 	require.NoError(t, err, "symlinking a file twice should not be an issue")
 
-	// Wait for touch() calls to be done.
+	// Wait for the manager to be done updating mtimes.
 	manager.wg.Wait()
 
 	// The blob should have been touched to indicate it was referenced just now.
@@ -89,6 +89,10 @@ func TestSymlinkToCheckout(t *testing.T) {
 	require.NoError(t, err)
 	assert.True(t, stat.Mode()&os.ModeType == os.ModeSymlink,
 		"%v should be a symlink", symlinkPath)
+
+	contents, err := os.ReadFile(symlinkPath)
+	require.NoError(t, err)
+	assert.Equal(t, string(contents), "op je hoofd")
 }
 
 func TestPrepareCheckout(t *testing.T) {