Merge branch '19088-s3-properties-tags'
[arvados.git] / sdk / go / arvados / fs_collection.go
index 2b5df76ad6a12d7e8e557efad006f3aa25f128d5..26012e240603d0be43a1019346c4e946e2821790 100644 (file)
@@ -44,8 +44,20 @@ type CollectionFileSystem interface {
 type collectionFileSystem struct {
        fileSystem
        uuid           string
+       savedPDH       atomic.Value
        replicas       int
        storageClasses []string
+       // guessSignatureTTL tracks a lower bound for the server's
+       // configured BlobSigningTTL. The guess is initially zero, and
+       // increases when we come across a signature with an expiry
+       // time further in the future than the previous guess.
+       //
+       // When the guessed TTL is much smaller than the real TTL,
+       // preemptive signature refresh is delayed or missed entirely,
+       // which is OK.
+       guessSignatureTTL time.Duration
+       holdCheckChanges  time.Time
+       lockCheckChanges  sync.Mutex
 }
 
 // FileSystem returns a CollectionFileSystem for the collection.
@@ -62,6 +74,7 @@ func (c *Collection) FileSystem(client apiClient, kc keepClient) (CollectionFile
                        thr:       newThrottle(concurrentWriters),
                },
        }
+       fs.savedPDH.Store(c.PortableDataHash)
        if r := c.ReplicationDesired; r != nil {
                fs.replicas = *r
        }
@@ -72,6 +85,7 @@ func (c *Collection) FileSystem(client apiClient, kc keepClient) (CollectionFile
                                name:    ".",
                                mode:    os.ModeDir | 0755,
                                modTime: modTime,
+                               sys:     func() interface{} { return c },
                        },
                        inodes: make(map[string]inode),
                },
@@ -85,16 +99,112 @@ func (c *Collection) FileSystem(client apiClient, kc keepClient) (CollectionFile
        return fs, nil
 }
 
-func backdateTree(n inode, modTime time.Time) {
+// caller must have lock (or guarantee no concurrent accesses somehow)
+func eachNode(n inode, ffunc func(*filenode), dfunc func(*dirnode)) {
        switch n := n.(type) {
        case *filenode:
-               n.fileinfo.modTime = modTime
+               if ffunc != nil {
+                       ffunc(n)
+               }
        case *dirnode:
-               n.fileinfo.modTime = modTime
+               if dfunc != nil {
+                       dfunc(n)
+               }
                for _, n := range n.inodes {
-                       backdateTree(n, modTime)
+                       eachNode(n, ffunc, dfunc)
+               }
+       }
+}
+
+// caller must have lock (or guarantee no concurrent accesses somehow)
+func backdateTree(n inode, modTime time.Time) {
+       eachNode(n, func(fn *filenode) {
+               fn.fileinfo.modTime = modTime
+       }, func(dn *dirnode) {
+               dn.fileinfo.modTime = modTime
+       })
+}
+
+// Approximate portion of signature TTL remaining, usually between 0
+// and 1, or negative if some signatures have expired.
+func (fs *collectionFileSystem) signatureTimeLeft() (float64, time.Duration) {
+       var (
+               now      = time.Now()
+               earliest = now.Add(time.Hour * 24 * 7 * 365)
+               latest   time.Time
+       )
+       fs.fileSystem.root.RLock()
+       eachNode(fs.root, func(fn *filenode) {
+               fn.Lock()
+               defer fn.Unlock()
+               for _, seg := range fn.segments {
+                       seg, ok := seg.(storedSegment)
+                       if !ok {
+                               continue
+                       }
+                       expiryTime, err := signatureExpiryTime(seg.locator)
+                       if err != nil {
+                               continue
+                       }
+                       if expiryTime.Before(earliest) {
+                               earliest = expiryTime
+                       }
+                       if expiryTime.After(latest) {
+                               latest = expiryTime
+                       }
                }
+       }, nil)
+       fs.fileSystem.root.RUnlock()
+
+       if latest.IsZero() {
+               // No signatures == 100% of TTL remaining.
+               return 1, 1
        }
+
+       ttl := latest.Sub(now)
+       fs.fileSystem.root.Lock()
+       {
+               if ttl > fs.guessSignatureTTL {
+                       // ttl is closer to the real TTL than
+                       // guessSignatureTTL.
+                       fs.guessSignatureTTL = ttl
+               } else {
+                       // Use the previous best guess to compute the
+                       // portion remaining (below, after unlocking
+                       // mutex).
+                       ttl = fs.guessSignatureTTL
+               }
+       }
+       fs.fileSystem.root.Unlock()
+
+       return earliest.Sub(now).Seconds() / ttl.Seconds(), ttl
+}
+
+func (fs *collectionFileSystem) updateSignatures(newmanifest string) {
+       newLoc := map[string]string{}
+       for _, tok := range regexp.MustCompile(`\S+`).FindAllString(newmanifest, -1) {
+               if mBlkRe.MatchString(tok) {
+                       newLoc[stripAllHints(tok)] = tok
+               }
+       }
+       fs.fileSystem.root.Lock()
+       defer fs.fileSystem.root.Unlock()
+       eachNode(fs.root, func(fn *filenode) {
+               fn.Lock()
+               defer fn.Unlock()
+               for idx, seg := range fn.segments {
+                       seg, ok := seg.(storedSegment)
+                       if !ok {
+                               continue
+                       }
+                       loc, ok := newLoc[stripAllHints(seg.locator)]
+                       if !ok {
+                               continue
+                       }
+                       seg.locator = loc
+                       fn.segments[idx] = seg
+               }
+       }, nil)
 }
 
 func (fs *collectionFileSystem) newNode(name string, perm os.FileMode, modTime time.Time) (node inode, err error) {
@@ -180,7 +290,88 @@ func (fs *collectionFileSystem) Truncate(int64) error {
        return ErrInvalidOperation
 }
 
+// Check for and incorporate upstream changes -- unless that has
+// already been done recently, in which case this func is a no-op.
+func (fs *collectionFileSystem) checkChangesOnServer() error {
+       if fs.uuid == "" && fs.savedPDH.Load() == "" {
+               return nil
+       }
+
+       // First try UUID if any, then last known PDH. Stop if all
+       // signatures are new enough.
+       checkingAll := false
+       for _, id := range []string{fs.uuid, fs.savedPDH.Load().(string)} {
+               if id == "" {
+                       continue
+               }
+
+               fs.lockCheckChanges.Lock()
+               if !checkingAll && fs.holdCheckChanges.After(time.Now()) {
+                       fs.lockCheckChanges.Unlock()
+                       return nil
+               }
+               remain, ttl := fs.signatureTimeLeft()
+               if remain > 0.01 && !checkingAll {
+                       fs.holdCheckChanges = time.Now().Add(ttl / 100)
+               }
+               fs.lockCheckChanges.Unlock()
+
+               if remain >= 0.5 {
+                       break
+               }
+               checkingAll = true
+               var coll Collection
+               err := fs.RequestAndDecode(&coll, "GET", "arvados/v1/collections/"+id, nil, map[string]interface{}{"select": []string{"portable_data_hash", "manifest_text"}})
+               if err != nil {
+                       continue
+               }
+               fs.updateSignatures(coll.ManifestText)
+       }
+       return nil
+}
+
+// Refresh signature on a single locator, if necessary. Assume caller
+// has lock. If an update is needed, and there are any storedSegments
+// whose signatures can be updated, start a background task to update
+// them asynchronously when the caller releases locks.
+func (fs *collectionFileSystem) refreshSignature(locator string) string {
+       exp, err := signatureExpiryTime(locator)
+       if err != nil || exp.Sub(time.Now()) > time.Minute {
+               // Synchronous update is not needed. Start an
+               // asynchronous update if needed.
+               go fs.checkChangesOnServer()
+               return locator
+       }
+       var manifests string
+       for _, id := range []string{fs.uuid, fs.savedPDH.Load().(string)} {
+               if id == "" {
+                       continue
+               }
+               var coll Collection
+               err := fs.RequestAndDecode(&coll, "GET", "arvados/v1/collections/"+id, nil, map[string]interface{}{"select": []string{"portable_data_hash", "manifest_text"}})
+               if err != nil {
+                       continue
+               }
+               manifests += coll.ManifestText
+       }
+       hash := stripAllHints(locator)
+       for _, tok := range regexp.MustCompile(`\S+`).FindAllString(manifests, -1) {
+               if mBlkRe.MatchString(tok) {
+                       if stripAllHints(tok) == hash {
+                               locator = tok
+                               break
+                       }
+               }
+       }
+       go fs.updateSignatures(manifests)
+       return locator
+}
+
 func (fs *collectionFileSystem) Sync() error {
+       err := fs.checkChangesOnServer()
+       if err != nil {
+               return err
+       }
        if fs.uuid == "" {
                return nil
        }
@@ -188,19 +379,34 @@ func (fs *collectionFileSystem) Sync() error {
        if err != nil {
                return fmt.Errorf("sync failed: %s", err)
        }
-       coll := &Collection{
+       if PortableDataHash(txt) == fs.savedPDH.Load() {
+               // No local changes since last save or initial load.
+               return nil
+       }
+       coll := Collection{
                UUID:         fs.uuid,
                ManifestText: txt,
        }
-       err = fs.RequestAndDecode(nil, "PUT", "arvados/v1/collections/"+fs.uuid, nil, map[string]interface{}{
+
+       selectFields := []string{"uuid", "portable_data_hash"}
+       fs.lockCheckChanges.Lock()
+       remain, _ := fs.signatureTimeLeft()
+       fs.lockCheckChanges.Unlock()
+       if remain < 0.5 {
+               selectFields = append(selectFields, "manifest_text")
+       }
+
+       err = fs.RequestAndDecode(&coll, "PUT", "arvados/v1/collections/"+fs.uuid, nil, map[string]interface{}{
                "collection": map[string]string{
                        "manifest_text": coll.ManifestText,
                },
-               "select": []string{"uuid"},
+               "select": selectFields,
        })
        if err != nil {
                return fmt.Errorf("sync failed: update %s: %s", fs.uuid, err)
        }
+       fs.updateSignatures(coll.ManifestText)
+       fs.savedPDH.Store(coll.PortableDataHash)
        return nil
 }
 
@@ -252,6 +458,14 @@ func (fs *collectionFileSystem) Size() int64 {
        return fs.fileSystem.root.(*dirnode).TreeSize()
 }
 
+func (fs *collectionFileSystem) Snapshot() (inode, error) {
+       return fs.fileSystem.root.Snapshot()
+}
+
+func (fs *collectionFileSystem) Splice(r inode) error {
+       return fs.fileSystem.root.Splice(r)
+}
+
 // filenodePtr is an offset into a file that is (usually) efficient to
 // seek to. Specifically, if filenode.repacked==filenodePtr.repacked
 // then
@@ -375,6 +589,10 @@ func (fn *filenode) Read(p []byte, startPtr filenodePtr) (n int, ptr filenodePtr
                err = io.EOF
                return
        }
+       if ss, ok := fn.segments[ptr.segmentIdx].(storedSegment); ok {
+               ss.locator = fn.fs.refreshSignature(ss.locator)
+               fn.segments[ptr.segmentIdx] = ss
+       }
        n, err = fn.segments[ptr.segmentIdx].ReadAt(p, int64(ptr.segmentOff))
        if n > 0 {
                ptr.off += int64(n)
@@ -667,6 +885,47 @@ func (fn *filenode) waitPrune() {
        }
 }
 
+func (fn *filenode) Snapshot() (inode, error) {
+       fn.RLock()
+       defer fn.RUnlock()
+       segments := make([]segment, 0, len(fn.segments))
+       for _, seg := range fn.segments {
+               segments = append(segments, seg.Slice(0, seg.Len()))
+       }
+       return &filenode{
+               fileinfo: fn.fileinfo,
+               segments: segments,
+       }, nil
+}
+
+func (fn *filenode) Splice(repl inode) error {
+       repl, err := repl.Snapshot()
+       if err != nil {
+               return err
+       }
+       fn.parent.Lock()
+       defer fn.parent.Unlock()
+       fn.Lock()
+       defer fn.Unlock()
+       _, err = fn.parent.Child(fn.fileinfo.name, func(inode) (inode, error) { return repl, nil })
+       if err != nil {
+               return err
+       }
+       switch repl := repl.(type) {
+       case *dirnode:
+               repl.parent = fn.parent
+               repl.fileinfo.name = fn.fileinfo.name
+               repl.setTreeFS(fn.fs)
+       case *filenode:
+               repl.parent = fn.parent
+               repl.fileinfo.name = fn.fileinfo.name
+               repl.fs = fn.fs
+       default:
+               return fmt.Errorf("cannot splice snapshot containing %T: %w", repl, ErrInvalidArgument)
+       }
+       return nil
+}
+
 type dirnode struct {
        fs *collectionFileSystem
        treenode
@@ -901,15 +1160,17 @@ func (dn *dirnode) MemorySize() (size int64) {
                case *dirnode:
                        size += node.MemorySize()
                case *filenode:
+                       size += 64
                        for _, seg := range node.segments {
                                switch seg := seg.(type) {
                                case *memSegment:
                                        size += int64(seg.Len())
                                }
+                               size += 64
                        }
                }
        }
-       return
+       return 64 + size
 }
 
 // caller must have write lock.
@@ -1280,6 +1541,86 @@ func (dn *dirnode) TreeSize() (bytes int64) {
        return
 }
 
+func (dn *dirnode) Snapshot() (inode, error) {
+       return dn.snapshot()
+}
+
+func (dn *dirnode) snapshot() (*dirnode, error) {
+       dn.RLock()
+       defer dn.RUnlock()
+       snap := &dirnode{
+               treenode: treenode{
+                       inodes:   make(map[string]inode, len(dn.inodes)),
+                       fileinfo: dn.fileinfo,
+               },
+       }
+       for name, child := range dn.inodes {
+               dupchild, err := child.Snapshot()
+               if err != nil {
+                       return nil, err
+               }
+               snap.inodes[name] = dupchild
+               dupchild.SetParent(snap, name)
+       }
+       return snap, nil
+}
+
+func (dn *dirnode) Splice(repl inode) error {
+       repl, err := repl.Snapshot()
+       if err != nil {
+               return fmt.Errorf("cannot copy snapshot: %w", err)
+       }
+       switch repl := repl.(type) {
+       default:
+               return fmt.Errorf("cannot splice snapshot containing %T: %w", repl, ErrInvalidArgument)
+       case *dirnode:
+               dn.Lock()
+               defer dn.Unlock()
+               dn.inodes = repl.inodes
+               dn.setTreeFS(dn.fs)
+       case *filenode:
+               dn.parent.Lock()
+               defer dn.parent.Unlock()
+               removing, err := dn.parent.Child(dn.fileinfo.name, nil)
+               if err != nil {
+                       return fmt.Errorf("cannot use Splice to replace a top-level directory with a file: %w", ErrInvalidOperation)
+               } else if removing != dn {
+                       // If ../thisdirname is not this dirnode, it
+                       // must be an inode that wraps a dirnode, like
+                       // a collectionFileSystem or deferrednode.
+                       if deferred, ok := removing.(*deferrednode); ok {
+                               // More useful to report the type of
+                               // the wrapped node rather than just
+                               // *deferrednode. (We know the real
+                               // inode is already loaded because dn
+                               // is inside it.)
+                               removing = deferred.realinode()
+                       }
+                       return fmt.Errorf("cannot use Splice to attach a file at top level of %T: %w", removing, ErrInvalidOperation)
+               }
+               dn.Lock()
+               defer dn.Unlock()
+               _, err = dn.parent.Child(dn.fileinfo.name, func(inode) (inode, error) { return repl, nil })
+               if err != nil {
+                       return fmt.Errorf("error replacing filenode: dn.parent.Child(): %w", err)
+               }
+               repl.fs = dn.fs
+       }
+       return nil
+}
+
+func (dn *dirnode) setTreeFS(fs *collectionFileSystem) {
+       dn.fs = fs
+       for _, child := range dn.inodes {
+               switch child := child.(type) {
+               case *dirnode:
+                       child.setTreeFS(fs)
+               case *filenode:
+                       child.fs = fs
+               }
+       }
+}
+
 type segment interface {
        io.ReaderAt
        Len() int