frostfs-node/pkg/services/object/get/assemble.go
Alex Vanin 20de74a505 Rename package name
Due to source code relocation from GitHub.

Signed-off-by: Alex Vanin <a.vanin@yadro.com>
2023-03-07 16:38:26 +03:00

254 lines
6.3 KiB
Go

package getsvc
import (
apistatus "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/client/status"
objectSDK "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object"
oid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/id"
"go.uber.org/zap"
)
func (exec *execCtx) assemble() {
if !exec.canAssemble() {
exec.log.Debug("can not assemble the object")
return
}
// Any access tokens are not expected to be used in the assembly process:
// - there is no requirement to specify child objects in session/bearer
// token for `GET`/`GETRANGE`/`RANGEHASH` requests in the API protocol,
// and, therefore, their missing in the original request should not be
// considered as error; on the other hand, without session for every child
// object, it is impossible to attach bearer token in the new generated
// requests correctly because the token has not been issued for that node's
// key;
// - the assembly process is expected to be handled on a container node
// only since the requests forwarding mechanism presentation; such the
// node should have enough rights for getting any child object by design.
exec.prm.common.ForgetTokens()
// Do not use forwarding during assembly stage.
// Request forwarding closure inherited in produced
// `execCtx` so it should be disabled there.
exec.disableForwarding()
exec.log.Debug("trying to assemble the object...")
splitInfo := exec.splitInfo()
childID, ok := splitInfo.Link()
if !ok {
childID, ok = splitInfo.LastPart()
if !ok {
exec.log.Debug("neither linking nor last part of split-chain is presented in split info")
return
}
}
prev, children := exec.initFromChild(childID)
if len(children) > 0 {
if exec.ctxRange() == nil {
if ok := exec.writeCollectedHeader(); ok {
exec.overtakePayloadDirectly(children, nil, true)
}
} else {
// TODO: #1155 choose one-by-one restoring algorithm according to size
// * if size > MAX => go right-to-left with HEAD and back with GET
// * else go right-to-left with GET and compose in single object before writing
if ok := exec.overtakePayloadInReverse(children[len(children)-1]); ok {
// payload of all children except the last are written, write last payload
exec.writeObjectPayload(exec.collectedObject)
}
}
} else if prev != nil {
if ok := exec.writeCollectedHeader(); ok {
// TODO: #1155 choose one-by-one restoring algorithm according to size
// * if size > MAX => go right-to-left with HEAD and back with GET
// * else go right-to-left with GET and compose in single object before writing
if ok := exec.overtakePayloadInReverse(*prev); ok {
// payload of all children except the last are written, write last payloa
exec.writeObjectPayload(exec.collectedObject)
}
}
} else {
exec.log.Debug("could not init parent from child")
}
}
func (exec *execCtx) initFromChild(obj oid.ID) (prev *oid.ID, children []oid.ID) {
log := exec.log.With(zap.Stringer("child ID", obj))
log.Debug("starting assembling from child")
child, ok := exec.getChild(obj, nil, true)
if !ok {
return
}
par := child.Parent()
if par == nil {
exec.status = statusUndefined
log.Debug("received child with empty parent")
return
}
exec.collectedObject = par
var payload []byte
if rng := exec.ctxRange(); rng != nil {
seekOff := rng.GetOffset()
seekLen := rng.GetLength()
seekTo := seekOff + seekLen
parSize := par.PayloadSize()
if seekTo < seekOff || parSize < seekOff || parSize < seekTo {
var errOutOfRange apistatus.ObjectOutOfRange
exec.err = &errOutOfRange
exec.status = statusOutOfRange
return
}
childSize := child.PayloadSize()
exec.curOff = parSize - childSize
from := uint64(0)
if exec.curOff < seekOff {
from = seekOff - exec.curOff
}
to := uint64(0)
if seekOff+seekLen > exec.curOff+from {
to = seekOff + seekLen - exec.curOff
}
payload = child.Payload()[from:to]
rng.SetLength(rng.GetLength() - to + from)
} else {
payload = child.Payload()
}
exec.collectedObject.SetPayload(payload)
idPrev, ok := child.PreviousID()
if ok {
return &idPrev, child.Children()
}
return nil, child.Children()
}
func (exec *execCtx) overtakePayloadDirectly(children []oid.ID, rngs []objectSDK.Range, checkRight bool) {
withRng := len(rngs) > 0 && exec.ctxRange() != nil
for i := range children {
var r *objectSDK.Range
if withRng {
r = &rngs[i]
}
child, ok := exec.getChild(children[i], r, !withRng && checkRight)
if !ok {
return
}
if ok := exec.writeObjectPayload(child); !ok {
return
}
}
exec.status = statusOK
exec.err = nil
}
func (exec *execCtx) overtakePayloadInReverse(prev oid.ID) bool {
chain, rngs, ok := exec.buildChainInReverse(prev)
if !ok {
return false
}
reverseRngs := len(rngs) > 0
// reverse chain
for left, right := 0, len(chain)-1; left < right; left, right = left+1, right-1 {
chain[left], chain[right] = chain[right], chain[left]
if reverseRngs {
rngs[left], rngs[right] = rngs[right], rngs[left]
}
}
exec.overtakePayloadDirectly(chain, rngs, false)
return exec.status == statusOK
}
func (exec *execCtx) buildChainInReverse(prev oid.ID) ([]oid.ID, []objectSDK.Range, bool) {
var (
chain = make([]oid.ID, 0)
rngs = make([]objectSDK.Range, 0)
seekRng = exec.ctxRange()
from = seekRng.GetOffset()
to = from + seekRng.GetLength()
withPrev = true
)
// fill the chain end-to-start
for withPrev {
// check that only for "range" requests,
// for `GET` it stops via the false `withPrev`
if seekRng != nil && exec.curOff <= from {
break
}
head, ok := exec.headChild(prev)
if !ok {
return nil, nil, false
}
if seekRng != nil {
sz := head.PayloadSize()
exec.curOff -= sz
if exec.curOff < to {
off := uint64(0)
if from > exec.curOff {
off = from - exec.curOff
sz -= from - exec.curOff
}
if to < exec.curOff+off+sz {
sz = to - off - exec.curOff
}
index := len(rngs)
rngs = append(rngs, objectSDK.Range{})
rngs[index].SetOffset(off)
rngs[index].SetLength(sz)
id, _ := head.ID()
chain = append(chain, id)
}
} else {
id, _ := head.ID()
chain = append(chain, id)
}
prev, withPrev = head.PreviousID()
}
return chain, rngs, true
}
func equalAddresses(a, b oid.Address) bool {
return a.Container().Equals(b.Container()) && a.Object().Equals(b.Object())
}