lotus/chain/events/events_called.go
Jakub Sztandera 96ade5f2dd
Cleanup more lint warnings
Signed-off-by: Jakub Sztandera <kubuxu@protocol.ai>
2020-06-02 18:38:41 +02:00

358 lines
9.2 KiB
Go

package events
import (
"context"
"math"
"sync"
"github.com/filecoin-project/specs-actors/actors/abi"
"github.com/ipfs/go-cid"
"golang.org/x/xerrors"
"github.com/filecoin-project/lotus/chain/types"
)
const NoTimeout = math.MaxInt64
type triggerID = uint64
// msgH is the block height at which a message was present / event has happened
type msgH = abi.ChainEpoch
// triggerH is the block height at which the listener will be notified about the
// message (msgH+confidence)
type triggerH = abi.ChainEpoch
// CalledHandler arguments:
// `ts` is the tipset, in which the `msg` is included.
// `curH`-`ts.Height` = `confidence`
type CalledHandler func(msg *types.Message, rec *types.MessageReceipt, ts *types.TipSet, curH abi.ChainEpoch) (more bool, err error)
// CheckFunc is used for atomicity guarantees. If the condition the callbacks
// wait for has already happened in tipset `ts`
//
// If `done` is true, timeout won't be triggered
// If `more` is false, no messages will be sent to CalledHandler (RevertHandler
// may still be called)
type CheckFunc func(ts *types.TipSet) (done bool, more bool, err error)
type MatchFunc func(msg *types.Message) (bool, error)
type callHandler struct {
confidence int
timeout abi.ChainEpoch
disabled bool // TODO: GC after gcConfidence reached
handle CalledHandler
revert RevertHandler
}
type queuedEvent struct {
trigger triggerID
h abi.ChainEpoch
msg *types.Message
called bool
}
type calledEvents struct {
cs eventAPI
tsc *tipSetCache
ctx context.Context
gcConfidence uint64
at abi.ChainEpoch
lk sync.Mutex
ctr triggerID
triggers map[triggerID]*callHandler
matchers map[triggerID][]MatchFunc
// maps block heights to events
// [triggerH][msgH][event]
confQueue map[triggerH]map[msgH][]*queuedEvent
// [msgH][triggerH]
revertQueue map[msgH][]triggerH
// [timeoutH+confidence][triggerID]{calls}
timeouts map[abi.ChainEpoch]map[triggerID]int
}
func (e *calledEvents) headChangeCalled(rev, app []*types.TipSet) error {
for _, ts := range rev {
e.handleReverts(ts)
e.at = ts.Height()
}
for _, ts := range app {
// called triggers
e.checkNewCalls(ts)
for ; e.at <= ts.Height(); e.at++ {
e.applyWithConfidence(ts, e.at)
e.applyTimeouts(ts)
}
}
return nil
}
func (e *calledEvents) handleReverts(ts *types.TipSet) {
reverts, ok := e.revertQueue[ts.Height()]
if !ok {
return // nothing to do
}
for _, triggerH := range reverts {
toRevert := e.confQueue[triggerH][ts.Height()]
for _, event := range toRevert {
if !event.called {
continue // event wasn't apply()-ied yet
}
trigger := e.triggers[event.trigger]
if err := trigger.revert(e.ctx, ts); err != nil {
log.Errorf("reverting chain trigger (call %s.%d() @H %d, called @ %d) failed: %s", event.msg.To, event.msg.Method, ts.Height(), triggerH, err)
}
}
delete(e.confQueue[triggerH], ts.Height())
}
delete(e.revertQueue, ts.Height())
}
func (e *calledEvents) checkNewCalls(ts *types.TipSet) {
pts, err := e.cs.ChainGetTipSet(e.ctx, ts.Parents()) // we actually care about messages in the parent tipset here
if err != nil {
log.Errorf("getting parent tipset in checkNewCalls: %s", err)
return
}
e.messagesForTs(pts, func(msg *types.Message) {
// TODO: provide receipts
for tid, matchFns := range e.matchers {
var matched bool
for _, matchFn := range matchFns {
ok, err := matchFn(msg)
if err != nil {
log.Errorf("event matcher failed: %s", err)
continue
}
matched = ok
if matched {
break
}
}
if matched {
e.queueForConfidence(tid, msg, ts)
break
}
}
})
}
func (e *calledEvents) queueForConfidence(trigID uint64, msg *types.Message, ts *types.TipSet) {
trigger := e.triggers[trigID]
appliedH := ts.Height()
triggerH := appliedH + abi.ChainEpoch(trigger.confidence)
byOrigH, ok := e.confQueue[triggerH]
if !ok {
byOrigH = map[abi.ChainEpoch][]*queuedEvent{}
e.confQueue[triggerH] = byOrigH
}
byOrigH[appliedH] = append(byOrigH[appliedH], &queuedEvent{
trigger: trigID,
h: appliedH,
msg: msg,
})
e.revertQueue[appliedH] = append(e.revertQueue[appliedH], triggerH)
}
func (e *calledEvents) applyWithConfidence(ts *types.TipSet, height abi.ChainEpoch) {
byOrigH, ok := e.confQueue[height]
if !ok {
return // no triggers at thin height
}
for origH, events := range byOrigH {
triggerTs, err := e.tsc.get(origH)
if err != nil {
log.Errorf("events: applyWithConfidence didn't find tipset for event; wanted %d; current %d", origH, height)
}
for _, event := range events {
if event.called {
continue
}
trigger := e.triggers[event.trigger]
if trigger.disabled {
continue
}
rec, err := e.cs.StateGetReceipt(e.ctx, event.msg.Cid(), ts.Key())
if err != nil {
log.Error(err)
return
}
more, err := trigger.handle(event.msg, rec, triggerTs, height)
if err != nil {
log.Errorf("chain trigger (call %s.%d() @H %d, called @ %d) failed: %s", event.msg.To, event.msg.Method, origH, height, err)
continue // don't revert failed calls
}
event.called = true
touts, ok := e.timeouts[trigger.timeout]
if ok {
touts[event.trigger]++
}
trigger.disabled = !more
}
}
}
func (e *calledEvents) applyTimeouts(ts *types.TipSet) {
triggers, ok := e.timeouts[ts.Height()]
if !ok {
return // nothing to do
}
for triggerID, calls := range triggers {
if calls > 0 {
continue // don't timeout if the method was called
}
trigger := e.triggers[triggerID]
if trigger.disabled {
continue
}
timeoutTs, err := e.tsc.get(ts.Height() - abi.ChainEpoch(trigger.confidence))
if err != nil {
log.Errorf("events: applyTimeouts didn't find tipset for event; wanted %d; current %d", ts.Height()-abi.ChainEpoch(trigger.confidence), ts.Height())
}
more, err := trigger.handle(nil, nil, timeoutTs, ts.Height())
if err != nil {
log.Errorf("chain trigger (call @H %d, called @ %d) failed: %s", timeoutTs.Height(), ts.Height(), err)
continue // don't revert failed calls
}
trigger.disabled = !more // allows messages after timeout
}
}
func (e *calledEvents) messagesForTs(ts *types.TipSet, consume func(*types.Message)) {
seen := map[cid.Cid]struct{}{}
for _, tsb := range ts.Blocks() {
msgs, err := e.cs.ChainGetBlockMessages(context.TODO(), tsb.Cid())
if err != nil {
log.Errorf("messagesForTs MessagesForBlock failed (ts.H=%d, Bcid:%s, B.Mcid:%s): %s", ts.Height(), tsb.Cid(), tsb.Messages, err)
// this is quite bad, but probably better than missing all the other updates
continue
}
for _, m := range msgs.BlsMessages {
_, ok := seen[m.Cid()]
if ok {
continue
}
seen[m.Cid()] = struct{}{}
consume(m)
}
for _, m := range msgs.SecpkMessages {
_, ok := seen[m.Message.Cid()]
if ok {
continue
}
seen[m.Message.Cid()] = struct{}{}
consume(&m.Message)
}
}
}
// Called registers a callbacks which are triggered when a specified method is
// called on an actor, or a timeout is reached.
//
// * `CheckFunc` callback is invoked immediately with a recent tipset, it
// returns two booleans - `done`, and `more`.
//
// * `done` should be true when some on-chain action we are waiting for has
// happened. When `done` is set to true, timeout trigger is disabled.
//
// * `more` should be false when we don't want to receive new notifications
// through CalledHandler. Note that notifications may still be delivered to
// RevertHandler
//
// * `CalledHandler` is called when the specified event was observed on-chain,
// and a confidence threshold was reached, or the specified `timeout` height
// was reached with no events observed. When this callback is invoked on a
// timeout, `msg` is set to nil. This callback returns a boolean specifying
// whether further notifications should be sent, like `more` return param
// from `CheckFunc` above.
//
// * `RevertHandler` is called after apply handler, when we drop the tipset
// containing the message. The tipset passed as the argument is the tipset
// that is being dropped. Note that the message dropped may be re-applied
// in a different tipset in small amount of time.
func (e *calledEvents) Called(check CheckFunc, hnd CalledHandler, rev RevertHandler, confidence int, timeout abi.ChainEpoch, mf MatchFunc) error {
e.lk.Lock()
defer e.lk.Unlock()
ts := e.tsc.best()
done, more, err := check(ts)
if err != nil {
return xerrors.Errorf("called check error (h: %d): %w", ts.Height(), err)
}
if done {
timeout = NoTimeout
}
id := e.ctr
e.ctr++
e.triggers[id] = &callHandler{
confidence: confidence,
timeout: timeout + abi.ChainEpoch(confidence),
disabled: !more,
handle: hnd,
revert: rev,
}
e.matchers[id] = append(e.matchers[id], mf)
if timeout != NoTimeout {
if e.timeouts[timeout+abi.ChainEpoch(confidence)] == nil {
e.timeouts[timeout+abi.ChainEpoch(confidence)] = map[uint64]int{}
}
e.timeouts[timeout+abi.ChainEpoch(confidence)][id] = 0
}
return nil
}
func (e *calledEvents) CalledMsg(ctx context.Context, hnd CalledHandler, rev RevertHandler, confidence int, timeout abi.ChainEpoch, msg types.ChainMsg) error {
return e.Called(e.CheckMsg(ctx, msg, hnd), hnd, rev, confidence, timeout, e.MatchMsg(msg.VMMessage()))
}