func doGood() {
// goodUIDs are UIDs with type.object.name containing "good".
results := expand(goodUIDs)
directorEdges := results["film.director.film"]
x.AssertTrue(len(directorEdges) > 100)
// Directors are UIDs which go to goodUIDs via "film.director.film".
directorUIDs, _ := uniqueUIDs(directorEdges)
results = expand(directorUIDs)
filmEdges := results["film.film.directed_by"]
x.AssertTrue(len(filmEdges) > 100)
// Films are UIDs which go to directorUIDs via "film.film.directed_by".
filmUIDs, _ := uniqueUIDs(filmEdges)
results = expand(filmUIDs)
directorEdges = results["film.director.film"]
x.AssertTrue(len(directorEdges) > 100)
// Directors are UIDs which go to filmUIDs via "film.director.film".
directorUIDs, counts := uniqueUIDs(directorEdges)
var maxCount int
var maxDirector uint64
for i, c := range counts {
if c > maxCount {
maxCount = c
maxDirector = directorUIDs[i]
}
}
fmt.Printf("maxDirector %d with count %d\n", maxDirector, maxCount)
}
// getPostingList tries to get posting list from l.pbuffer. If it is nil, then
// we query RocksDB. There is no need for lock acquisition here.
func (l *List) getPostingList(loop int) *types.PostingList {
if loop >= 10 {
x.Fatalf("This is over the 10th loop: %v", loop)
}
l.AssertRLock()
// Wait for any previous commits to happen before retrieving posting list again.
l.Wait()
pb := atomic.LoadPointer(&l.pbuffer)
plist := (*types.PostingList)(pb)
if plist == nil {
x.AssertTrue(l.pstore != nil)
plist = new(types.PostingList)
if slice, err := l.pstore.Get(l.key); err == nil && slice != nil {
x.Checkf(plist.Unmarshal(slice.Data()), "Unable to Unmarshal PostingList from store")
slice.Free()
}
if atomic.CompareAndSwapPointer(&l.pbuffer, pb, unsafe.Pointer(plist)) {
return plist
}
// Someone else replaced the pointer in the meantime. Retry recursively.
return l.getPostingList(loop + 1)
}
return plist
}
func parseDefaultConfig(l string) (uint32, error) {
// If we have already seen a default config line, and n has a value then we
// log.Fatal.
if groupConfig.n != 0 {
return 0, fmt.Errorf("Default config can only be defined once: %v", l)
}
l = strings.TrimSpace(l)
conf := strings.Split(l, " ")
// + in (fp % n + k) is optional.
if !(len(conf) == 5 || len(conf) == 3) || conf[0] != "fp" || conf[1] != "%" {
return 0, fmt.Errorf("Default config format should be like: %v", "default: fp % n + k")
}
var err error
var n uint64
n, err = strconv.ParseUint(conf[2], 10, 32)
x.Check(err)
groupConfig.n = uint32(n)
x.AssertTrue(groupConfig.n != 0)
if len(conf) == 5 {
if conf[3] != "+" {
return 0, fmt.Errorf("Default config format should be like: %v", "default: fp % n + k")
}
n, err = strconv.ParseUint(conf[4], 10, 32)
groupConfig.k = uint32(n)
x.Check(err)
}
return groupConfig.k, nil
}
func (p *poolsi) connect(addr string) {
if addr == *myAddr {
return
}
p.RLock()
_, has := p.all[addr]
p.RUnlock()
if has {
return
}
pool := newPool(addr, 5)
query := new(Payload)
query.Data = make([]byte, 10)
x.Check2(rand.Read(query.Data))
conn, err := pool.Get()
x.Checkf(err, "Unable to connect")
c := NewWorkerClient(conn)
resp, err := c.Echo(context.Background(), query)
x.Checkf(err, "Unable to Echo")
x.AssertTrue(bytes.Equal(resp.Data, query.Data))
x.Check(pool.Put(conn))
fmt.Printf("Connection with %q successful.\n", addr)
p.Lock()
defer p.Unlock()
_, has = p.all[addr]
if has {
return
}
p.all[addr] = pool
}
// newQuery creates a Query task and returns it.
func newQuery(attr string, uids []uint64, srcFunc []string) *task.Query {
x.AssertTrue(uids == nil || srcFunc == nil)
return &task.Query{
Uids: uids,
SrcFunc: srcFunc,
Attr: attr,
}
}
func (n *node) processMembership(e raftpb.Entry, mm *task.Membership) error {
x.AssertTrue(n.gid == 0)
x.Printf("group: %v Addr: %q leader: %v dead: %v\n",
mm.GroupId, mm.Addr, mm.Leader, mm.AmDead)
groups().applyMembershipUpdate(e.Index, mm)
return nil
}
func parsePeer(peer string) (uint64, string) {
x.AssertTrue(len(peer) > 0)
kv := strings.SplitN(peer, ":", 2)
x.AssertTruef(len(kv) == 2, "Invalid peer format: %v", peer)
pid, err := strconv.ParseUint(kv[0], 10, 64)
x.Checkf(err, "Invalid peer id: %v", kv[0])
// TODO: Validate the url kv[1]
return pid, kv[1]
}
// initIndex initializes the index with the given data store.
func initIndex() {
x.AssertTrue(pstore != nil)
// Initialize TokensTables.
indexedFields := schema.IndexedFields()
type resultStruct struct {
attr string
table *TokensTable
}
results := make(chan resultStruct, len(indexedFields))
for _, attr := range indexedFields {
go func(attr string) {
table := &TokensTable{
key: make([]string, 0, 50),
}
pk := x.ParsedKey{
Attr: attr,
}
prefix := pk.IndexPrefix()
it := pstore.NewIterator()
defer it.Close()
for it.Seek(prefix); it.ValidForPrefix(prefix); it.Next() {
pki := x.Parse(it.Key().Data())
x.AssertTrue(pki.IsIndex())
x.AssertTrue(len(pki.Term) > 0)
table.push(pki.Term)
}
results <- resultStruct{attr, table}
}(attr)
}
tables = make(map[string]*TokensTable)
for i := 0; i < len(indexedFields); i++ {
r := <-results
tables[r.attr] = r.table
}
}
// newSort creates a task.Sort for sorting.
func newSort(uids [][]uint64, offset, count int) *task.Sort {
x.AssertTrue(uids != nil)
uidMatrix := make([]*task.List, len(uids))
for i, l := range uids {
uidMatrix[i] = &task.List{Uids: l}
}
return &task.Sort{
Attr: "dob",
Offset: int32(offset),
Count: int32(count),
UidMatrix: uidMatrix,
}
}
// applyWindow applies windowing to sg.sorted.
func (sg *SubGraph) applyPagination(ctx context.Context) error {
params := sg.Params
if params.Count == 0 && params.Offset == 0 { // No pagination.
return nil
}
x.AssertTrue(len(sg.SrcUIDs.Uids) == len(sg.uidMatrix))
for _, l := range sg.uidMatrix {
algo.IntersectWith(l, sg.DestUIDs)
start, end := pageRange(&sg.Params, len(l.Uids))
l.Uids = l.Uids[start:end]
}
// Re-merge the UID matrix.
sg.DestUIDs = algo.MergeSorted(sg.uidMatrix)
return nil
}
// stringHelper does simple DFS to convert FilterTree to string.
func (t *FilterTree) stringHelper(buf *bytes.Buffer) {
x.AssertTrue(t != nil)
if t.Func != nil && len(t.Func.Name) > 0 {
// Leaf node.
_, err := buf.WriteRune('(')
x.Check(err)
_, err = buf.WriteString(t.Func.Name)
x.Check(err)
if len(t.Func.Attr) > 0 {
args := make([]string, len(t.Func.Args)+1)
args[0] = t.Func.Attr
copy(args[1:], t.Func.Args)
for _, arg := range args {
_, err = buf.WriteString(" \"")
x.Check(err)
_, err = buf.WriteString(arg)
x.Check(err)
_, err := buf.WriteRune('"')
x.Check(err)
}
}
_, err = buf.WriteRune(')')
x.Check(err)
return
}
// Non-leaf node.
_, err := buf.WriteRune('(')
x.Check(err)
switch t.Op {
case "&":
_, err = buf.WriteString("AND")
case "|":
_, err = buf.WriteString("OR")
default:
err = x.Errorf("Unknown operator: %q", t.Op)
}
x.Check(err)
for _, c := range t.Child {
_, err = buf.WriteRune(' ')
x.Check(err)
c.stringHelper(buf)
}
_, err = buf.WriteRune(')')
x.Check(err)
}
func main() {
x.Init()
s = &status{
start: time.Now(),
}
filesList := strings.Split(*files, ",")
x.AssertTrue(len(filesList) > 0)
for _, file := range filesList {
processFile(file)
}
fmt.Printf("Number of mutations run : %d\n", s.mutations)
fmt.Printf("Number of RDFs processed : %d\n", s.rdfs)
fmt.Printf("Time spent : %v\n", time.Since(s.start))
fmt.Printf("RDFs processed per second : %d\n", s.rdfs/uint64(time.Since(s.start).Seconds()))
}
func expand(uids []uint64, pred string) []uint64 {
x.AssertTrue(graph != nil)
var out []uint64
for p, m := range graph {
if pred != p {
continue
}
for _, u := range uids {
dst := m[u]
if dst == nil {
continue
}
out = append(out, dst...)
}
}
return out
}
func expand(uids []uint64) map[string]map[uint64][]uint64 {
x.AssertTrue(invGraph != nil)
out := make(map[string]map[uint64][]uint64)
for pred, m := range invGraph {
outM := make(map[uint64][]uint64)
for _, u := range uids { // srcUID.
z := m[u]
if z == nil {
continue
}
outM[u] = z
}
if len(outM) > 0 {
out[pred] = outM
}
}
return out
}
// applyOrderAndPagination orders each posting list by a given attribute
// before applying pagination.
func (sg *SubGraph) applyOrderAndPagination(ctx context.Context) error {
if len(sg.Params.Order) == 0 {
return nil
}
if sg.Params.Count == 0 {
// Only retrieve up to 1000 results by default.
sg.Params.Count = 1000
}
sort := &task.Sort{
Attr: sg.Params.Order,
UidMatrix: sg.uidMatrix,
Offset: int32(sg.Params.Offset),
Count: int32(sg.Params.Count),
Desc: sg.Params.OrderDesc,
}
result, err := worker.SortOverNetwork(ctx, sort)
if err != nil {
return err
}
x.AssertTrue(len(result.UidMatrix) == len(sg.uidMatrix))
sg.uidMatrix = result.GetUidMatrix()
// Update sg.destUID. Iterate over the UID matrix (which is not sorted by
// UID). For each element in UID matrix, we do a binary search in the
// current destUID and mark it. Then we scan over this bool array and
// rebuild destUIDs.
included := make([]bool, len(sg.DestUIDs.Uids))
for _, ul := range sg.uidMatrix {
for _, uid := range ul.Uids {
idx := algo.IndexOf(sg.DestUIDs, uid) // Binary search.
if idx >= 0 {
included[idx] = true
}
}
}
algo.ApplyFilter(sg.DestUIDs,
func(uid uint64, idx int) bool { return included[idx] })
return nil
}
// addIndexMutations adds mutation(s) for a single term, to maintain index.
func addIndexMutations(ctx context.Context, attr string, uid uint64,
p types.Value, del bool) {
x.AssertTrue(uid != 0)
tokens, err := IndexTokens(attr, p)
if err != nil {
// This data is not indexable
return
}
edge := &task.DirectedEdge{
ValueId: uid,
Attr: attr,
Label: "idx",
}
tokensTable := GetTokensTable(attr)
x.AssertTruef(tokensTable != nil, "TokensTable missing for attr %s", attr)
for _, token := range tokens {
addIndexMutation(ctx, attr, token, tokensTable, edge, del)
}
}
func batchCommit() {
var sz int
var waits []*x.SafeWait
var loop uint64
b := pstore.NewWriteBatch()
defer b.Destroy()
for {
select {
case e := <-commitCh:
b.Put(e.key, e.val)
sz++
waits = append(waits, e.sw)
default:
// default is executed if no other case is ready.
start := time.Now()
if sz > 0 {
x.AssertTrue(b != nil)
loop++
fmt.Printf("[%4d] Writing batch of size: %v\n", loop, sz)
x.Checkf(pstore.WriteBatch(b), "Error while writing to RocksDB.")
for _, w := range waits {
w.Done()
}
b.Clear()
sz = 0
waits = waits[:0]
}
// Add a sleep clause to avoid a busy wait loop if there's no input to commitCh.
sleepFor := 10*time.Millisecond - time.Since(start)
if sleepFor > time.Millisecond {
time.Sleep(sleepFor)
}
}
}
}
// NewTokenizer creates a new Tokenizer object from a given input string of bytes.
func NewTokenizer(s []byte) (*Tokenizer, error) {
x.AssertTrue(s != nil)
if disableICU {
// ICU is disabled. Return a dummy tokenizer.
return &Tokenizer{}, nil
}
sNorm, terr := normalize(s)
if terr != nil {
return nil, terr
}
sNorm = append(sNorm, 0) // Null-terminate this for ICU's C functions.
var err C.UErrorCode
c := C.NewTokenizer(byteToChar(sNorm), C.int(len(s)), maxTokenSize, &err)
if int(err) > 0 {
return nil, x.Errorf("ICU new tokenizer error %d", int(err))
}
if c == nil {
return nil, x.Errorf("NewTokenizer returns nil")
}
return &Tokenizer{c, C.TokenizerToken(c)}, nil
}
func (l *List) updateMutationLayer(mpost *types.Posting) bool {
l.AssertLock()
x.AssertTrue(mpost.Op == Set || mpost.Op == Del)
// First check the mutable layer.
midx := sort.Search(len(l.mlayer), func(idx int) bool {
mp := l.mlayer[idx]
return mpost.Uid <= mp.Uid
})
// This block handles the case where mpost.UID is found in mutation layer.
if midx < len(l.mlayer) && l.mlayer[midx].Uid == mpost.Uid {
// mp is the posting found in mlayer.
oldPost := l.mlayer[midx]
// Note that mpost.Op is either Set or Del, whereas oldPost.Op can be
// either Set or Del or Add.
msame := samePosting(oldPost, mpost)
if msame && ((mpost.Op == Del) == (oldPost.Op == Del)) {
// This posting has similar content as what is found in mlayer. If the
// ops are similar, then we do nothing. Note that Add and Set are
// considered similar, and the second clause is true also when
// mpost.Op==Add and oldPost.Op==Set.
return false
}
if !msame && mpost.Op == Del {
// Invalid Del as contents do not match.
return false
}
// Here are the remaining cases.
// Del, Set: Replace with new post.
// Del, Del: Replace with new post.
// Set, Del: Replace with new post.
// Set, Set: Replace with new post.
// Add, Del: Undo by removing oldPost.
// Add, Set: Replace with new post. Need to set mpost.Op to Add.
if oldPost.Op == Add {
if mpost.Op == Del {
// Undo old post.
copy(l.mlayer[midx:], l.mlayer[midx+1:])
l.mlayer[len(l.mlayer)-1] = nil
l.mlayer = l.mlayer[:len(l.mlayer)-1]
return true
}
// Add followed by Set is considered an Add. Hence, mutate mpost.Op.
mpost.Op = Add
}
l.mlayer[midx] = mpost
return true
}
// Didn't find it in mutable layer. Now check the immutable layer.
pl := l.getPostingList(0)
pidx := sort.Search(len(pl.Postings), func(idx int) bool {
p := pl.Postings[idx]
return mpost.Uid <= p.Uid
})
var uidFound, psame bool
if pidx < len(pl.Postings) {
p := pl.Postings[pidx]
uidFound = mpost.Uid == p.Uid
if uidFound {
psame = samePosting(p, mpost)
}
}
if mpost.Op == Set {
if psame {
return false
}
if !uidFound {
// Posting not found in PL. This is considered an Add operation.
mpost.Op = Add
}
} else if !psame { // mpost.Op==Del
// Either we fail to find UID in immutable PL or contents don't match.
return false
}
// Doesn't match what we already have in immutable layer. So, add to mutable layer.
if midx >= len(l.mlayer) {
// Add it at the end.
l.mlayer = append(l.mlayer, mpost)
return true
}
// Otherwise, add it where midx is pointing to.
l.mlayer = append(l.mlayer, nil)
copy(l.mlayer[midx+1:], l.mlayer[midx:])
l.mlayer[midx] = mpost
return true
}
func main() {
x.Init()
fin, err := os.Open(filename)
x.Check(err)
defer fin.Close()
scanner := bufio.NewScanner(fin)
var numLines, numValues, numNames, numReleaseDates int
invGraph = make(map[string]map[uint64][]uint64)
for scanner.Scan() {
numLines++
tokens := strings.Split(scanner.Text(), "\t")
x.AssertTruef(len(tokens) == 4, scanner.Text())
src := tokens[0]
x.AssertTrue(bracketed(src))
src = removeFirstLast(src)
srcUID := farm.Fingerprint64([]byte(src))
pred := tokens[1]
x.AssertTrue(bracketed(pred))
pred = removeFirstLast(pred)
value := tokens[2]
if bracketed(value) {
// Normal edge.
value = removeFirstLast(value)
destUID := farm.Fingerprint64([]byte(value))
m, found := invGraph[pred]
if !found {
m = make(map[uint64][]uint64)
invGraph[pred] = m
}
// We are building an inverse map!
m[destUID] = append(m[destUID], srcUID)
} else {
// A value.
numValues++
value = removeFirstLast(value)
if pred == "type.object.name" {
numNames++
// Do some custom processing here.
value = strings.ToLower(value)
vTokens := strings.Split(value, " ")
var found bool
for _, t := range vTokens {
if t == "the" {
found = true
break
}
}
if found {
goodUIDs = append(goodUIDs, srcUID)
}
} else if pred == "film.film.initial_release_date" {
numReleaseDates++
}
}
}
fmt.Printf("Num lines read: %d\n", numLines)
fmt.Printf("Num predicates: %d\n", len(invGraph))
fmt.Printf("Num values read: %d\n", numValues)
fmt.Printf("Num names read: %d\n", numNames)
fmt.Printf("Num release dates read: %d\n", numReleaseDates)
fmt.Printf("Num good UIDs: %d\n", len(goodUIDs))
x.AssertTrue(numLines > 0)
x.AssertTrue(len(invGraph) > 0)
x.AssertTrue(numValues > 0)
x.AssertTrue(numNames > 0)
x.AssertTrue(numReleaseDates > 0)
x.AssertTrue(len(goodUIDs) > 0)
doGood()
}
// Backup creates a backup of data by exporting it as an RDF gzip.
func backup(gid uint32, bdir string) error {
// Use a goroutine to write to file.
err := os.MkdirAll(bdir, 0700)
if err != nil {
return err
}
fpath := path.Join(bdir, fmt.Sprintf("dgraph-%d-%s.rdf.gz", gid,
time.Now().Format("2006-01-02-15-04")))
fmt.Printf("Backing up at: %v\n", fpath)
chb := make(chan []byte, 1000)
errChan := make(chan error, 1)
go func() {
errChan <- writeToFile(fpath, chb)
}()
// Use a bunch of goroutines to convert to RDF format.
chkv := make(chan kv, 1000)
var wg sync.WaitGroup
wg.Add(numBackupRoutines)
for i := 0; i < numBackupRoutines; i++ {
go func() {
buf := new(bytes.Buffer)
buf.Grow(50000)
for item := range chkv {
toRDF(buf, item)
if buf.Len() >= 40000 {
tmp := make([]byte, buf.Len())
copy(tmp, buf.Bytes())
chb <- tmp
buf.Reset()
}
}
if buf.Len() > 0 {
tmp := make([]byte, buf.Len())
copy(tmp, buf.Bytes())
chb <- tmp
}
wg.Done()
}()
}
// Iterate over rocksdb.
it := pstore.NewIterator()
defer it.Close()
var lastPred string
for it.SeekToFirst(); it.Valid(); {
key := it.Key().Data()
pk := x.Parse(key)
if pk.IsIndex() {
// Seek to the end of index keys.
it.Seek(pk.SkipRangeOfSameType())
continue
}
if pk.Attr == "_uid_" {
// Skip the UID mappings.
it.Seek(pk.SkipPredicate())
continue
}
x.AssertTrue(pk.IsData())
pred, uid := pk.Attr, pk.Uid
if pred != lastPred && group.BelongsTo(pred) != gid {
it.Seek(pk.SkipPredicate())
continue
}
prefix := fmt.Sprintf("<_uid_:%#x> <%s> ", uid, pred)
pl := &types.PostingList{}
x.Check(pl.Unmarshal(it.Value().Data()))
chkv <- kv{
prefix: prefix,
list: pl,
}
lastPred = pred
it.Next()
}
close(chkv) // We have stopped output to chkv.
wg.Wait() // Wait for numBackupRoutines to finish.
close(chb) // We have stopped output to chb.
err = <-errChan
return err
}
func intersectBucket(ts *task.Sort, attr, token string, out []intersectedList) error {
count := int(ts.Count)
sType := schema.TypeOf(attr)
if !sType.IsScalar() {
return x.Errorf("Cannot sort attribute %s of type object.", attr)
}
scalar := sType.(types.Scalar)
key := x.IndexKey(attr, token)
pl, decr := posting.GetOrCreate(key)
defer decr()
for i, ul := range ts.UidMatrix {
il := &out[i]
if count > 0 && len(il.ulist.Uids) >= count {
continue
}
// Intersect index with i-th input UID list.
listOpt := posting.ListOptions{Intersect: ul}
result := pl.Uids(listOpt)
n := len(result.Uids)
// Check offsets[i].
if il.offset >= n {
// We are going to skip the whole intersection. No need to do actual
// sorting. Just update offsets[i].
il.offset -= n
continue
}
// Sort results by value before applying offset.
sortByValue(attr, result, scalar, ts.Desc)
if il.offset > 0 {
result.Uids = result.Uids[il.offset:n]
il.offset = 0
n = len(result.Uids)
}
// n is number of elements to copy from result to out.
if count > 0 {
slack := count - len(il.ulist.Uids)
if slack < n {
n = slack
}
}
// Copy from result to out.
for j := 0; j < n; j++ {
il.ulist.Uids = append(il.ulist.Uids, result.Uids[j])
}
} // end for loop
// Check out[i] sizes for all i.
for i := 0; i < len(ts.UidMatrix); i++ { // Iterate over UID lists.
if len(out[i].ulist.Uids) < count {
return errContinue
}
x.AssertTrue(len(out[i].ulist.Uids) == count)
}
return errDone
}
// processTask processes the query, accumulates and returns the result.
func processTask(q *task.Query) (*task.Result, error) {
attr := q.Attr
useFunc := len(q.SrcFunc) != 0
var n int
var tokens []string
var geoQuery *geo.QueryData
var err error
var intersectDest bool
var ineqValue types.Value
var ineqValueToken string
var isGeq, isLeq bool
if useFunc {
f := q.SrcFunc[0]
isGeq = f == "geq"
isLeq = f == "leq"
switch {
case isGeq:
fallthrough
case isLeq:
if len(q.SrcFunc) != 2 {
return nil, x.Errorf("Function requires 2 arguments, but got %d %v",
len(q.SrcFunc), q.SrcFunc)
}
ineqValue, err = getValue(attr, q.SrcFunc[1])
if err != nil {
return nil, err
}
// Tokenizing RHS value of inequality.
ineqTokens, err := posting.IndexTokens(attr, ineqValue)
if err != nil {
return nil, err
}
if len(ineqTokens) != 1 {
return nil, x.Errorf("Expected only 1 token but got: %v", ineqTokens)
}
ineqValueToken = ineqTokens[0]
// Get tokens geq / leq ineqValueToken.
tokens, err = getInequalityTokens(attr, ineqValueToken, isGeq)
if err != nil {
return nil, err
}
case geo.IsGeoFunc(q.SrcFunc[0]):
// For geo functions, we get extra information used for filtering.
tokens, geoQuery, err = geo.GetTokens(q.SrcFunc)
if err != nil {
return nil, err
}
default:
tokens, err = getTokens(q.SrcFunc)
if err != nil {
return nil, err
}
intersectDest = (strings.ToLower(q.SrcFunc[0]) == "allof")
}
n = len(tokens)
} else {
n = len(q.Uids)
}
var out task.Result
for i := 0; i < n; i++ {
var key []byte
if useFunc {
key = x.IndexKey(attr, tokens[i])
} else {
key = x.DataKey(attr, q.Uids[i])
}
// Get or create the posting list for an entity, attribute combination.
pl, decr := posting.GetOrCreate(key)
defer decr()
// If a posting list contains a value, we store that or else we store a nil
// byte so that processing is consistent later.
vbytes, vtype, err := pl.Value()
newValue := &task.Value{ValType: uint32(vtype)}
if err == nil {
newValue.Val = vbytes
} else {
newValue.Val = x.Nilbyte
}
out.Values = append(out.Values, newValue)
if q.DoCount {
out.Counts = append(out.Counts, uint32(pl.Length(0)))
// Add an empty UID list to make later processing consistent
out.UidMatrix = append(out.UidMatrix, &emptyUIDList)
continue
}
// The more usual case: Getting the UIDs.
opts := posting.ListOptions{
AfterUID: uint64(q.AfterUid),
}
// If we have srcFunc and Uids, it means its a filter. So we intersect.
if useFunc && len(q.Uids) > 0 {
opts.Intersect = &task.List{Uids: q.Uids}
}
out.UidMatrix = append(out.UidMatrix, pl.Uids(opts))
}
if (isGeq || isLeq) && len(tokens) > 0 && ineqValueToken == tokens[0] {
// Need to evaluate inequality for entries in the first bucket.
typ := schema.TypeOf(attr)
if typ == nil || !typ.IsScalar() {
return nil, x.Errorf("Attribute not scalar: %s %v", attr, typ)
}
scalarType := typ.(types.Scalar)
x.AssertTrue(len(out.UidMatrix) > 0)
// Filter the first row of UidMatrix. Since ineqValue != nil, we may
// assume that ineqValue is equal to the first token found in TokensTable.
algo.ApplyFilter(out.UidMatrix[0], func(uid uint64, i int) bool {
key := x.DataKey(attr, uid)
sv := getPostingValue(key, scalarType)
if sv == nil {
return false
}
if isGeq {
return !scalarType.Less(*sv, ineqValue)
}
return !scalarType.Less(ineqValue, *sv)
})
}
// If geo filter, do value check for correctness.
var values []*task.Value
if geoQuery != nil {
uids := algo.MergeSorted(out.UidMatrix)
for _, uid := range uids.Uids {
key := x.DataKey(attr, uid)
pl, decr := posting.GetOrCreate(key)
vbytes, vtype, err := pl.Value()
newValue := &task.Value{ValType: uint32(vtype)}
if err == nil {
newValue.Val = vbytes
} else {
newValue.Val = x.Nilbyte
}
values = append(values, newValue)
decr() // Decrement the reference count of the pl.
}
filtered := geo.FilterUids(uids, values, geoQuery)
for i := 0; i < len(out.UidMatrix); i++ {
out.UidMatrix[i] = algo.IntersectSorted([]*task.List{out.UidMatrix[i], filtered})
}
}
out.IntersectDest = intersectDest
return &out, nil
}
func main() {
x.Init()
fin, err := os.Open(filename)
x.Check(err)
defer fin.Close()
scanner := bufio.NewScanner(fin)
var numLines, numValues, numNames, numReleaseDates int
graph = make(map[string]map[uint64][]uint64)
gNames = make(map[uint64]string)
gReleaseDates = make(map[uint64]string)
for scanner.Scan() {
numLines++
tokens := strings.Split(scanner.Text(), "\t")
x.AssertTruef(len(tokens) == 4, scanner.Text())
src := tokens[0]
x.AssertTrue(bracketed(src))
src = removeFirstLast(src)
srcUID := farm.Fingerprint64([]byte(src))
pred := tokens[1]
x.AssertTrue(bracketed(pred))
pred = removeFirstLast(pred)
value := tokens[2]
if bracketed(value) {
// Normal edge.
value = removeFirstLast(value)
destUID := farm.Fingerprint64([]byte(value))
m, found := graph[pred]
if !found {
m = make(map[uint64][]uint64)
graph[pred] = m
}
m[srcUID] = append(m[srcUID], destUID)
} else {
numValues++
// Check for "@".
pos := strings.LastIndex(value, "@")
if pos >= 0 {
pred = pred + "." + value[pos+1:]
value = removeFirstLast(value[:pos])
}
if pred == "type.object.name.en" {
numNames++
gNames[srcUID] = value
} else if pred == "film.film.initial_release_date" {
numReleaseDates++
gReleaseDates[srcUID] = value
}
}
}
fmt.Printf("Num lines read: %d\n", numLines)
fmt.Printf("Num predicates: %d\n", len(graph))
fmt.Printf("Num values read: %d\n", numValues)
fmt.Printf("Num names read: %d\n", numNames)
fmt.Printf("Num release dates read: %d\n", numReleaseDates)
x.AssertTrue(numLines > 0)
x.AssertTrue(len(graph) > 0)
x.AssertTrue(numValues > 0)
x.AssertTrue(numNames > 0)
x.AssertTrue(numReleaseDates > 0)
// doFilterString()
// doSortRelease()
doGen()
}
// ProcessGraph processes the SubGraph instance accumulating result for the query
// from different instances. Note: taskQuery is nil for root node.
func ProcessGraph(ctx context.Context, sg, parent *SubGraph, rch chan error) {
var err error
if len(sg.Attr) == 0 {
// If we have a filter SubGraph which only contains an operator,
// it won't have any attribute to work on.
// This is to allow providing SrcUIDs to the filter children.
sg.DestUIDs = sg.SrcUIDs
} else if parent == nil && len(sg.SrcFunc) == 0 {
// I am root. I don't have any function to execute, and my
// result has been prepared for me already.
sg.DestUIDs = algo.MergeSorted(sg.uidMatrix) // Could also be = sg.SrcUIDs
} else {
taskQuery := createTaskQuery(sg)
result, err := worker.ProcessTaskOverNetwork(ctx, taskQuery)
if err != nil {
x.TraceError(ctx, x.Wrapf(err, "Error while processing task"))
rch <- err
return
}
sg.uidMatrix = result.UidMatrix
sg.values = result.Values
if len(sg.values) > 0 {
v := sg.values[0]
x.Trace(ctx, "Sample value for attr: %v Val: %v", sg.Attr, string(v.Val))
}
sg.counts = result.Counts
if sg.Params.DoCount && len(sg.Filters) == 0 {
// If there is a filter, we need to do more work to get the actual count.
x.Trace(ctx, "Zero uids. Only count requested")
rch <- nil
return
}
if result.IntersectDest {
sg.DestUIDs = algo.IntersectSorted(result.UidMatrix)
} else {
sg.DestUIDs = algo.MergeSorted(result.UidMatrix)
}
}
if len(sg.DestUIDs.Uids) == 0 {
// Looks like we're done here. Be careful with nil srcUIDs!
x.Trace(ctx, "Zero uids for %q. Num attr children: %v", sg.Attr, len(sg.Children))
rch <- nil
return
}
// Apply filters if any.
if len(sg.Filters) > 0 {
// Run all filters in parallel.
filterChan := make(chan error, len(sg.Filters))
for _, filter := range sg.Filters {
filter.SrcUIDs = sg.DestUIDs
go ProcessGraph(ctx, filter, sg, filterChan)
}
for _ = range sg.Filters {
select {
case err = <-filterChan:
if err != nil {
x.TraceError(ctx, x.Wrapf(err, "Error while processing filter task"))
rch <- err
return
}
case <-ctx.Done():
x.TraceError(ctx, x.Wrapf(ctx.Err(), "Context done before full execution"))
rch <- ctx.Err()
return
}
}
// Now apply the results from filter.
var lists []*task.List
for _, filter := range sg.Filters {
lists = append(lists, filter.DestUIDs)
}
if sg.FilterOp == "|" {
sg.DestUIDs = algo.MergeSorted(lists)
} else {
sg.DestUIDs = algo.IntersectSorted(lists)
}
}
if len(sg.Params.Order) == 0 {
// There is no ordering. Just apply pagination and return.
if err = sg.applyPagination(ctx); err != nil {
rch <- err
return
}
} else {
// We need to sort first before pagination.
if err = sg.applyOrderAndPagination(ctx); err != nil {
rch <- err
return
}
}
// Here we consider handling _count_ with filtering. We do this after
// pagination because otherwise, we need to do the count with pagination
// taken into account. For example, a PL might have only 50 entries but the
// user wants to skip 100 entries and return 10 entries. In this case, you
// should return a count of 0, not 10.
if sg.Params.DoCount {
x.AssertTrue(len(sg.Filters) > 0)
sg.counts = make([]uint32, len(sg.uidMatrix))
for i, ul := range sg.uidMatrix {
// A possible optimization is to return the size of the intersection
// without forming the intersection.
algo.IntersectWith(ul, sg.DestUIDs)
sg.counts[i] = uint32(len(ul.Uids))
}
rch <- nil
return
}
childChan := make(chan error, len(sg.Children))
for i := 0; i < len(sg.Children); i++ {
child := sg.Children[i]
child.SrcUIDs = sg.DestUIDs // Make the connection.
go ProcessGraph(ctx, child, sg, childChan)
}
// Now get all the results back.
for _ = range sg.Children {
select {
case err = <-childChan:
if err != nil {
x.TraceError(ctx, x.Wrapf(err, "Error while processing child task"))
rch <- err
return
}
case <-ctx.Done():
x.TraceError(ctx, x.Wrapf(ctx.Err(), "Context done before full execution"))
rch <- ctx.Err()
return
}
}
rch <- nil
}
