X-Git-Url: https://git.arvados.org/arvados.git/blobdiff_plain/18c8fa2337a2db04ee6060184885731f4b5c7d7b..13c69930bbec6f691100e4374ba272905fd83f3e:/sdk/go/arvados/fs_collection.go

diff --git a/sdk/go/arvados/fs_collection.go b/sdk/go/arvados/fs_collection.go
index fc00335ce5..b996542abd 100644
--- a/sdk/go/arvados/fs_collection.go
+++ b/sdk/go/arvados/fs_collection.go
@@ -8,7 +8,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"log"
 	"os"
 	"path"
 	"regexp"
@@ -21,28 +20,6 @@ import (
 
 var maxBlockSize = 1 << 26
 
-type fsBackend interface {
-	keepClient
-	apiClient
-}
-
-// Ideally *Client would do everything; meanwhile keepBackend
-// implements fsBackend by merging the two kinds of arvados client.
-type keepBackend struct {
-	keepClient
-	apiClient
-}
-
-type keepClient interface {
-	ReadAt(locator string, p []byte, off int) (int, error)
-	PutB(p []byte) (string, int, error)
-}
-
-type apiClient interface {
-	RequestAndDecode(dst interface{}, method, path string, body io.Reader, params interface{}) error
-	UpdateBody(rsc resource) io.Reader
-}
-
 // A CollectionFileSystem is a FileSystem that can be serialized as a
 // manifest and stored as a collection.
 type CollectionFileSystem interface {
@@ -53,6 +30,14 @@ type CollectionFileSystem interface {
 	// Prefix (normally ".") is a top level directory, effectively
 	// prepended to all paths in the returned manifest.
 	MarshalManifest(prefix string) (string, error)
+
+	// Total data bytes in all files.
+	Size() int64
+}
+
+type collectionFileSystem struct {
+	fileSystem
+	uuid string
 }
 
 // FileSystem returns a CollectionFileSystem for the collection.
@@ -64,14 +49,14 @@ func (c *Collection) FileSystem(client apiClient, kc keepClient) (CollectionFile
 		modTime = *c.ModifiedAt
 	}
 	fs := &collectionFileSystem{
+		uuid: c.UUID,
 		fileSystem: fileSystem{
 			fsBackend: keepBackend{apiClient: client, keepClient: kc},
 		},
-		uuid: c.UUID,
 	}
-	dn := &dirnode{
+	root := &dirnode{
+		fs: fs,
 		treenode: treenode{
-			fs: fs,
 			fileinfo: fileinfo{
 				name:    ".",
 				mode:    os.ModeDir | 0755,
@@ -80,28 +65,62 @@ func (c *Collection) FileSystem(client apiClient, kc keepClient) (CollectionFile
 			inodes: make(map[string]inode),
 		},
 	}
-	dn.parent = dn
-	fs.fileSystem.root = dn
-	if err := dn.loadManifest(c.ManifestText); err != nil {
+	root.SetParent(root, ".")
+	if err := root.loadManifest(c.ManifestText); err != nil {
 		return nil, err
 	}
+	backdateTree(root, modTime)
+	fs.root = root
 	return fs, nil
 }
 
-type collectionFileSystem struct {
-	fileSystem
-	uuid string
+func backdateTree(n inode, modTime time.Time) {
+	switch n := n.(type) {
+	case *filenode:
+		n.fileinfo.modTime = modTime
+	case *dirnode:
+		n.fileinfo.modTime = modTime
+		for _, n := range n.inodes {
+			backdateTree(n, modTime)
+		}
+	}
+}
+
+func (fs *collectionFileSystem) newNode(name string, perm os.FileMode, modTime time.Time) (node inode, err error) {
+	if name == "" || name == "." || name == ".." {
+		return nil, ErrInvalidArgument
+	}
+	if perm.IsDir() {
+		return &dirnode{
+			fs: fs,
+			treenode: treenode{
+				fileinfo: fileinfo{
+					name:    name,
+					mode:    perm | os.ModeDir,
+					modTime: modTime,
+				},
+				inodes: make(map[string]inode),
+			},
+		}, nil
+	} else {
+		return &filenode{
+			fs: fs,
+			fileinfo: fileinfo{
+				name:    name,
+				mode:    perm & ^os.ModeDir,
+				modTime: modTime,
+			},
+		}, nil
+	}
 }
 
 func (fs *collectionFileSystem) Sync() error {
-	log.Printf("cfs.Sync()")
 	if fs.uuid == "" {
 		return nil
 	}
 	txt, err := fs.MarshalManifest(".")
 	if err != nil {
-		log.Printf("WARNING: (collectionFileSystem)Sync() failed: %s", err)
-		return err
+		return fmt.Errorf("sync failed: %s", err)
 	}
 	coll := &Collection{
 		UUID:         fs.uuid,
@@ -109,28 +128,9 @@ func (fs *collectionFileSystem) Sync() error {
 	}
 	err = fs.RequestAndDecode(nil, "PUT", "arvados/v1/collections/"+fs.uuid, fs.UpdateBody(coll), map[string]interface{}{"select": []string{"uuid"}})
 	if err != nil {
-		log.Printf("WARNING: (collectionFileSystem)Sync() failed: %s", err)
+		return fmt.Errorf("sync failed: update %s: %s", fs.uuid, err)
 	}
-	return err
-}
-
-func (fs *collectionFileSystem) Child(name string, replace func(inode) inode) inode {
-	if name == ".arvados#collection" {
-		return &getternode{Getter: func() ([]byte, error) {
-			var coll Collection
-			var err error
-			coll.ManifestText, err = fs.MarshalManifest(".")
-			if err != nil {
-				return nil, err
-			}
-			data, err := json.Marshal(&coll)
-			if err == nil {
-				data = append(data, 10)
-			}
-			return data, err
-		}}
-	}
-	return fs.fileSystem.root.Child(name, replace)
+	return nil
 }
 
 func (fs *collectionFileSystem) MarshalManifest(prefix string) (string, error) {
@@ -139,6 +139,10 @@ func (fs *collectionFileSystem) MarshalManifest(prefix string) (string, error) {
 	return fs.fileSystem.root.(*dirnode).marshalManifest(prefix)
 }
 
+func (fs *collectionFileSystem) Size() int64 {
+	return fs.fileSystem.root.(*dirnode).TreeSize()
+}
+
 // filenodePtr is an offset into a file that is (usually) efficient to
 // seek to. Specifically, if filenode.repacked==filenodePtr.repacked
 // then
@@ -232,6 +236,13 @@ func (fn *filenode) appendSegment(e segment) {
 	fn.fileinfo.size += int64(e.Len())
 }
 
+func (fn *filenode) SetParent(p inode, name string) {
+	fn.Lock()
+	defer fn.Unlock()
+	fn.parent = p
+	fn.fileinfo.name = name
+}
+
 func (fn *filenode) Parent() inode {
 	fn.RLock()
 	defer fn.RUnlock()
@@ -487,7 +498,7 @@ func (fn *filenode) pruneMemSegments() {
 		if !ok || seg.Len() < maxBlockSize {
 			continue
 		}
-		locator, _, err := fn.parent.(fsBackend).PutB(seg.buf)
+		locator, _, err := fn.FS().PutB(seg.buf)
 		if err != nil {
 			// TODO: stall (or return errors from)
 			// subsequent writes until flushing
@@ -496,7 +507,7 @@ func (fn *filenode) pruneMemSegments() {
 		}
 		fn.memsize -= int64(seg.Len())
 		fn.segments[idx] = storedSegment{
-			kc:      fn.parent.(fsBackend),
+			kc:      fn.FS(),
 			locator: locator,
 			size:    seg.Len(),
 			offset:  0,
@@ -506,12 +517,40 @@ func (fn *filenode) pruneMemSegments() {
 }
 
 type dirnode struct {
+	fs *collectionFileSystem
 	treenode
 }
 
-// sync flushes in-memory data (for all files in the tree rooted at
-// dn) to persistent storage. Caller must hold dn.Lock().
-func (dn *dirnode) sync() error {
+func (dn *dirnode) FS() FileSystem {
+	return dn.fs
+}
+
+func (dn *dirnode) Child(name string, replace func(inode) (inode, error)) (inode, error) {
+	if dn == dn.fs.rootnode() && name == ".arvados#collection" {
+		gn := &getternode{Getter: func() ([]byte, error) {
+			var coll Collection
+			var err error
+			coll.ManifestText, err = dn.fs.MarshalManifest(".")
+			if err != nil {
+				return nil, err
+			}
+			data, err := json.Marshal(&coll)
+			if err == nil {
+				data = append(data, '\n')
+			}
+			return data, err
+		}}
+		gn.SetParent(dn, name)
+		return gn, nil
+	}
+	return dn.treenode.Child(name, replace)
+}
+
+// sync flushes in-memory data and remote block references (for the
+// children with the given names, which must be children of dn) to
+// local persistent storage. Caller must have write lock on dn and the
+// named children.
+func (dn *dirnode) sync(names []string) error {
 	type shortBlock struct {
 		fn  *filenode
 		idx int
@@ -547,45 +586,51 @@ func (dn *dirnode) sync() error {
 		return nil
 	}
 
-	names := make([]string, 0, len(dn.inodes))
-	for name := range dn.inodes {
-		names = append(names, name)
-	}
-	sort.Strings(names)
-
+	localLocator := map[string]string{}
 	for _, name := range names {
 		fn, ok := dn.inodes[name].(*filenode)
 		if !ok {
 			continue
 		}
-		fn.Lock()
-		defer fn.Unlock()
 		for idx, seg := range fn.segments {
-			seg, ok := seg.(*memSegment)
-			if !ok {
-				continue
-			}
-			if seg.Len() > maxBlockSize/2 {
-				if err := flush([]shortBlock{{fn, idx}}); err != nil {
-					return err
+			switch seg := seg.(type) {
+			case storedSegment:
+				loc, ok := localLocator[seg.locator]
+				if !ok {
+					var err error
+					loc, err = dn.fs.LocalLocator(seg.locator)
+					if err != nil {
+						return err
+					}
+					localLocator[seg.locator] = loc
 				}
-				continue
-			}
-			if pendingLen+seg.Len() > maxBlockSize {
-				if err := flush(pending); err != nil {
-					return err
+				seg.locator = loc
+				fn.segments[idx] = seg
+			case *memSegment:
+				if seg.Len() > maxBlockSize/2 {
+					if err := flush([]shortBlock{{fn, idx}}); err != nil {
+						return err
+					}
+					continue
+				}
+				if pendingLen+seg.Len() > maxBlockSize {
+					if err := flush(pending); err != nil {
+						return err
+					}
+					pending = nil
+					pendingLen = 0
 				}
-				pending = nil
-				pendingLen = 0
+				pending = append(pending, shortBlock{fn, idx})
+				pendingLen += seg.Len()
+			default:
+				panic(fmt.Sprintf("can't sync segment type %T", seg))
 			}
-			pending = append(pending, shortBlock{fn, idx})
-			pendingLen += seg.Len()
 		}
 	}
 	return flush(pending)
 }
 
-// caller must have read lock.
+// caller must have write lock.
 func (dn *dirnode) marshalManifest(prefix string) (string, error) {
 	var streamLen int64
 	type filepart struct {
@@ -597,18 +642,30 @@ func (dn *dirnode) marshalManifest(prefix string) (string, error) {
 	var subdirs string
 	var blocks []string
 
-	if err := dn.sync(); err != nil {
-		return "", err
+	if len(dn.inodes) == 0 {
+		if prefix == "." {
+			return "", nil
+		}
+		// Express the existence of an empty directory by
+		// adding an empty file named `\056`, which (unlike
+		// the more obvious spelling `.`) is accepted by the
+		// API's manifest validator.
+		return manifestEscape(prefix) + " d41d8cd98f00b204e9800998ecf8427e+0 0:0:\\056\n", nil
 	}
 
 	names := make([]string, 0, len(dn.inodes))
-	for name, node := range dn.inodes {
+	for name := range dn.inodes {
 		names = append(names, name)
+	}
+	sort.Strings(names)
+	for _, name := range names {
+		node := dn.inodes[name]
 		node.Lock()
 		defer node.Unlock()
 	}
-	sort.Strings(names)
-
+	if err := dn.sync(names); err != nil {
+		return "", err
+	}
 	for _, name := range names {
 		switch node := dn.inodes[name].(type) {
 		case *dirnode:
@@ -724,8 +781,14 @@ func (dn *dirnode) loadManifest(txt string) error {
 			}
 			name := dirname + "/" + manifestUnescape(toks[2])
 			fnode, err := dn.createFileAndParents(name)
-			if err != nil {
-				return fmt.Errorf("line %d: cannot use path %q: %s", lineno, name, err)
+			if fnode == nil && err == nil && length == 0 {
+				// Special case: an empty file used as
+				// a marker to preserve an otherwise
+				// empty directory in a manifest.
+				continue
+			}
+			if err != nil || (fnode == nil && length != 0) {
+				return fmt.Errorf("line %d: cannot use path %q with length %d: %s", lineno, name, length, err)
 			}
 			// Map the stream offset/range coordinates to
 			// block/offset/range coordinates and add
@@ -783,15 +846,14 @@ func (dn *dirnode) loadManifest(txt string) error {
 	return nil
 }
 
-// only safe to call from loadManifest -- no locking
+// only safe to call from loadManifest -- no locking.
+//
+// If path is a "parent directory exists" marker (the last path
+// component is "."), the returned values are both nil.
 func (dn *dirnode) createFileAndParents(path string) (fn *filenode, err error) {
 	var node inode = dn
 	names := strings.Split(path, "/")
 	basename := names[len(names)-1]
-	if basename == "" || basename == "." || basename == ".." {
-		err = fmt.Errorf("invalid filename")
-		return
-	}
 	for _, name := range names[:len(names)-1] {
 		switch name {
 		case "", ".":
@@ -801,44 +863,69 @@ func (dn *dirnode) createFileAndParents(path string) (fn *filenode, err error) {
 				// can't be sure parent will be a *dirnode
 				return nil, ErrInvalidArgument
 			}
-			node = node.Parent().(*dirnode)
+			node = node.Parent()
 			continue
 		}
-		node.Child(name, func(child inode) inode {
+		node, err = node.Child(name, func(child inode) (inode, error) {
 			if child == nil {
-				node, err = node.FS().newDirnode(node, name, 0755|os.ModeDir, node.Parent().FileInfo().ModTime())
-				child = node
+				child, err := node.FS().newNode(name, 0755|os.ModeDir, node.Parent().FileInfo().ModTime())
+				if err != nil {
+					return nil, err
+				}
+				child.SetParent(node, name)
+				return child, nil
 			} else if !child.IsDir() {
-				err = ErrFileExists
+				return child, ErrFileExists
 			} else {
-				node = child
+				return child, nil
 			}
-			return child
 		})
 		if err != nil {
 			return
 		}
 	}
-	node.Child(basename, func(child inode) inode {
+	if basename == "." {
+		return
+	} else if !permittedName(basename) {
+		err = fmt.Errorf("invalid file part %q in path %q", basename, path)
+		return
+	}
+	_, err = node.Child(basename, func(child inode) (inode, error) {
 		switch child := child.(type) {
 		case nil:
-			child, err = node.FS().newFilenode(node, basename, 0755, node.FileInfo().ModTime())
+			child, err = node.FS().newNode(basename, 0755, node.FileInfo().ModTime())
+			if err != nil {
+				return nil, err
+			}
+			child.SetParent(node, basename)
 			fn = child.(*filenode)
-			return child
+			return child, nil
 		case *filenode:
 			fn = child
-			return child
+			return child, nil
 		case *dirnode:
-			err = ErrIsDirectory
-			return child
+			return child, ErrIsDirectory
 		default:
-			err = ErrInvalidOperation
-			return child
+			return child, ErrInvalidArgument
 		}
 	})
 	return
 }
 
+func (dn *dirnode) TreeSize() (bytes int64) {
+	dn.RLock()
+	defer dn.RUnlock()
+	for _, i := range dn.inodes {
+		switch i := i.(type) {
+		case *filenode:
+			bytes += i.Size()
+		case *dirnode:
+			bytes += i.TreeSize()
+		}
+	}
+	return
+}
+
 type segment interface {
 	io.ReaderAt
 	Len() int