Files
dolt/go/store/datas/commit_closure.go

453 lines
12 KiB
Go

// Copyright 2022 Dolthub, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package datas
import (
"context"
"errors"
"fmt"
"io"
"github.com/dolthub/dolt/go/gen/fb/serial"
"github.com/dolthub/dolt/go/store/chunks"
"github.com/dolthub/dolt/go/store/hash"
"github.com/dolthub/dolt/go/store/prolly"
"github.com/dolthub/dolt/go/store/prolly/tree"
"github.com/dolthub/dolt/go/store/types"
)
func NewParentsClosure(ctx context.Context, c *Commit, sv types.SerialMessage, vr types.ValueReader, ns tree.NodeStore) (prolly.CommitClosure, error) {
var msg serial.Commit
err := serial.InitCommitRoot(&msg, sv, serial.MessagePrefixSz)
if err != nil {
return prolly.CommitClosure{}, err
}
addr := hash.New(msg.ParentClosureBytes())
if addr.IsEmpty() {
return prolly.CommitClosure{}, nil
}
v, err := vr.ReadValue(ctx, addr)
if err != nil {
return prolly.CommitClosure{}, err
}
if types.IsNull(v) {
return prolly.CommitClosure{}, fmt.Errorf("internal error or data loss: dangling commit parent closure for addr %s or commit %s", addr.String(), c.Addr().String())
}
node, err := tree.NodeFromBytes(v.(types.SerialMessage))
if err != nil {
return prolly.CommitClosure{}, err
}
return prolly.NewCommitClosure(node, ns)
}
func newParentsClosureIterator(ctx context.Context, c *Commit, vr types.ValueReader, ns tree.NodeStore) (parentsClosureIter, error) {
sv := c.NomsValue()
if sm, ok := sv.(types.SerialMessage); ok {
cc, err := NewParentsClosure(ctx, c, sm, vr, ns)
if err != nil {
return nil, err
}
if cc.IsEmpty() {
return nil, nil
}
ci, err := cc.IterAllReverse(ctx)
if err != nil {
return nil, err
}
return &fbParentsClosureIterator{i: ci, curr: prolly.NewCommitClosureKey(ns.Pool(), c.Height(), c.Addr()), err: nil}, nil
}
s, ok := sv.(types.Struct)
if !ok {
return nil, fmt.Errorf("target ref is not struct: %v", sv)
}
if s.Name() != commitName {
return nil, fmt.Errorf("target ref is not commit: %v", sv)
}
fv, ok, err := s.MaybeGet(parentsClosureField)
if err != nil {
return nil, err
}
if !ok {
return nil, nil
}
mr, ok := fv.(types.Ref)
if !ok {
return nil, fmt.Errorf("value of parents_closure field is not Ref: %v", fv)
}
mv, err := mr.TargetValue(ctx, vr)
if err != nil {
return nil, err
}
m, ok := mv.(types.Map)
if !ok {
return nil, fmt.Errorf("target value of parents_closure Ref is not Map: %v", mv)
}
maxKeyTuple, err := types.NewTuple(vr.Format(), types.Uint(18446744073709551615))
if err != nil {
return nil, err
}
mi, err := m.IteratorBackFrom(ctx, maxKeyTuple)
if err != nil {
return nil, err
}
initialCurr, err := commitToMapKeyTuple(vr.Format(), c)
if err != nil {
return nil, err
}
return &parentsClosureIterator{mi, nil, initialCurr}, nil
}
func commitToMapKeyTuple(f *types.NomsBinFormat, c *Commit) (types.Tuple, error) {
h := c.Addr()
ib := make([]byte, len(hash.Hash{}))
copy(ib, h[:])
return types.NewTuple(f, types.Uint(c.Height()), types.InlineBlob(ib))
}
type parentsClosureIter interface {
Err() error
Hash() hash.Hash
Height() uint64
Less(ctx context.Context, nbf *types.NomsBinFormat, itr parentsClosureIter) bool
Next(context.Context) bool
}
type parentsClosureIterator struct {
mi types.MapIterator
err error
curr types.Tuple
}
func (i *parentsClosureIterator) Err() error {
return i.err
}
func (i *parentsClosureIterator) Height() uint64 {
if i.err != nil {
return 0
}
field, err := i.curr.Get(0)
if err != nil {
i.err = err
return 0
}
return uint64(field.(types.Uint))
}
func (i *parentsClosureIterator) Hash() hash.Hash {
if i.err != nil {
return hash.Hash{}
}
var h hash.Hash
field, err := i.curr.Get(1)
if err != nil {
i.err = err
return hash.Hash{}
}
ib, ok := field.(types.InlineBlob)
if !ok {
i.err = fmt.Errorf("second field of tuple key parents closure should have been InlineBlob")
return hash.Hash{}
}
copy(h[:], []byte(ib))
return h
}
func (i *parentsClosureIterator) Less(ctx context.Context, nbf *types.NomsBinFormat, otherI parentsClosureIter) bool {
other := otherI.(*parentsClosureIterator)
if i.err != nil || other.err != nil {
return false
}
ret, err := i.curr.Less(ctx, nbf, other.curr)
if err != nil {
i.err = err
other.err = err
return false
}
return ret
}
func (i *parentsClosureIterator) Next(ctx context.Context) bool {
if i.err != nil {
return false
}
n, _, err := i.mi.Next(ctx)
if err != nil {
i.err = err
return false
}
if n == nil || types.IsNull(n) {
return false
}
t, ok := n.(types.Tuple)
if !ok {
i.err = fmt.Errorf("key value of parents closure map should have been Tuple")
return false
}
i.curr = t
return true
}
type fbParentsClosureIterator struct {
i prolly.CommitClosureIter
curr prolly.CommitClosureKey
err error
}
func (i *fbParentsClosureIterator) Err() error {
return i.err
}
func (i *fbParentsClosureIterator) Height() uint64 {
if i.err != nil {
return 0
}
return i.curr.Height()
}
func (i *fbParentsClosureIterator) Hash() hash.Hash {
if i.err != nil {
return hash.Hash{}
}
return i.curr.Addr()
}
func (i *fbParentsClosureIterator) Next(ctx context.Context) bool {
if i.err != nil {
return false
}
i.curr, _, i.err = i.i.Next(ctx)
if i.err == io.EOF {
i.err = nil
return false
}
return true
}
func (i *fbParentsClosureIterator) Less(ctx context.Context, nbf *types.NomsBinFormat, otherI parentsClosureIter) bool {
other := otherI.(*fbParentsClosureIterator)
return i.curr.Less(other.curr)
}
func writeTypesCommitParentClosure(ctx context.Context, vrw types.ValueReadWriter, parentRefsL types.List) (types.Ref, bool, error) {
parentRefs := make([]types.Ref, int(parentRefsL.Len()))
parents := make([]types.Struct, len(parentRefs))
if len(parents) == 0 {
return types.Ref{}, false, nil
}
err := parentRefsL.IterAll(ctx, func(v types.Value, i uint64) error {
r, ok := v.(types.Ref)
if !ok {
return errors.New("parentsRef element was not a Ref")
}
parentRefs[int(i)] = r
tv, err := r.TargetValue(ctx, vrw)
if err != nil {
return err
}
s, ok := tv.(types.Struct)
if !ok {
return errors.New("parentRef target value was not a Struct")
}
parents[int(i)] = s
return nil
})
if err != nil {
return types.Ref{}, false, err
}
parentMaps := make([]types.Map, len(parents))
parentParentLists := make([]types.List, len(parents))
for i, p := range parents {
v, ok, err := p.MaybeGet(parentsClosureField)
if err != nil {
return types.Ref{}, false, err
}
if !ok || types.IsNull(v) {
empty, err := types.NewMap(ctx, vrw)
if err != nil {
return types.Ref{}, false, err
}
parentMaps[i] = empty
} else {
r, ok := v.(types.Ref)
if !ok {
return types.Ref{}, false, errors.New("unexpected field value type for parents_closure in commit struct")
}
tv, err := r.TargetValue(ctx, vrw)
if err != nil {
return types.Ref{}, false, err
}
parentMaps[i], ok = tv.(types.Map)
if !ok {
return types.Ref{}, false, fmt.Errorf("unexpected target value type for parents_closure in commit struct: %v", tv)
}
}
v, ok, err = p.MaybeGet(parentsListField)
if err != nil {
return types.Ref{}, false, err
}
if !ok || types.IsNull(v) {
empty, err := types.NewList(ctx, vrw)
if err != nil {
return types.Ref{}, false, err
}
parentParentLists[i] = empty
} else {
parentParentLists[i], ok = v.(types.List)
if !ok {
return types.Ref{}, false, errors.New("unexpected field value or type for parents_list in commit struct")
}
}
if parentMaps[i].Len() == 0 && parentParentLists[i].Len() != 0 {
// If one of the commits has an empty parents_closure, but non-empty parents, we will not record
// a parents_closure here.
return types.Ref{}, false, nil
}
}
// Convert parent lists to List<Ref<Value>>
for i, l := range parentParentLists {
newRefs := make([]types.Value, int(l.Len()))
err := l.IterAll(ctx, func(v types.Value, i uint64) error {
r, ok := v.(types.Ref)
if !ok {
return errors.New("unexpected entry type for parents_list in commit struct")
}
newRefs[int(i)], err = types.ToRefOfValue(r, vrw.Format())
if err != nil {
return err
}
return nil
})
if err != nil {
return types.Ref{}, false, err
}
parentParentLists[i], err = types.NewList(ctx, vrw, newRefs...)
if err != nil {
return types.Ref{}, false, err
}
}
editor := parentMaps[0].Edit()
for i, r := range parentRefs {
h := r.TargetHash()
key, err := types.NewTuple(vrw.Format(), types.Uint(r.Height()), types.InlineBlob(h[:]))
if err != nil {
editor.Close(ctx)
return types.Ref{}, false, err
}
editor.Set(key, parentParentLists[i])
}
for i := 1; i < len(parentMaps); i++ {
changes := make(chan types.ValueChanged)
var derr error
go func() {
defer close(changes)
derr = parentMaps[1].Diff(ctx, parentMaps[0], changes)
}()
for c := range changes {
if c.ChangeType == types.DiffChangeAdded {
editor.Set(c.Key, c.NewValue)
}
}
if derr != nil {
editor.Close(ctx)
return types.Ref{}, false, derr
}
}
m, err := editor.Map(ctx)
if err != nil {
return types.Ref{}, false, err
}
r, err := vrw.WriteValue(ctx, m)
if err != nil {
return types.Ref{}, false, err
}
r, err = types.ToRefOfValue(r, vrw.Format())
if err != nil {
return types.Ref{}, false, err
}
return r, true, nil
}
func writeFbCommitParentClosure(ctx context.Context, cs chunks.ChunkStore, vrw types.ValueReadWriter, ns tree.NodeStore, parents []*serial.Commit, parentAddrs []hash.Hash) (hash.Hash, error) {
if len(parents) == 0 {
// We write an empty hash for parent-less commits of height 1.
return hash.Hash{}, nil
}
// Fetch the parent closures of our parents.
addrs := make([]hash.Hash, len(parents))
for i := range parents {
addrs[i] = hash.New(parents[i].ParentClosureBytes())
}
vs, err := vrw.ReadManyValues(ctx, addrs)
if err != nil {
return hash.Hash{}, fmt.Errorf("writeCommitParentClosure: ReadManyValues: %w", err)
}
// Load them as ProllyTrees.
closures := make([]prolly.CommitClosure, len(parents))
for i := range addrs {
if !types.IsNull(vs[i]) {
node, err := tree.NodeFromBytes(vs[i].(types.SerialMessage))
if err != nil {
return hash.Hash{}, err
}
closures[i], err = prolly.NewCommitClosure(node, ns)
if err != nil {
return hash.Hash{}, err
}
} else {
closures[i], err = prolly.NewEmptyCommitClosure(ns)
if err != nil {
return hash.Hash{}, err
}
}
}
// Add all the missing entries from [1, ...) maps to the 0th map.
editor := closures[0].Editor()
for i := 1; i < len(closures); i++ {
err = prolly.DiffCommitClosures(ctx, closures[0], closures[i], func(ctx context.Context, diff tree.Diff) error {
if diff.Type == tree.AddedDiff {
return editor.Add(ctx, prolly.CommitClosureKey(diff.Key))
}
return nil
})
if err != nil && !errors.Is(err, io.EOF) {
return hash.Hash{}, fmt.Errorf("writeCommitParentClosure: DiffCommitClosures: %w", err)
}
}
// Add the parents themselves to the new map.
for i := 0; i < len(parents); i++ {
err = editor.Add(ctx, prolly.NewCommitClosureKey(ns.Pool(), parents[i].Height(), parentAddrs[i]))
if err != nil {
return hash.Hash{}, fmt.Errorf("writeCommitParentClosure: MutableCommitClosure.Put: %w", err)
}
}
// This puts the closure in the NodeStore as well.
res, err := editor.Flush(ctx)
if err != nil {
return hash.Hash{}, fmt.Errorf("writeCommitParentClosure: MutableCommitClosure.Flush: %w", err)
}
return res.HashOf(), nil
}