package v2
|
|
|
|
import (
|
|
"fmt"
|
|
"strings"
|
|
"sync/atomic"
|
|
|
|
"github.com/Workiva/go-datastructures/queue"
|
|
|
|
"github.com/tendermint/tendermint/libs/log"
|
|
)
|
|
|
|
type handleFunc = func(event Event) (Event, error)
|
|
|
|
const historySize = 25
|
|
|
|
// Routine is a structure that models a finite state machine as serialized
|
|
// stream of events processed by a handle function. This Routine structure
|
|
// handles the concurrency and messaging guarantees. Events are sent via
|
|
// `send` are handled by the `handle` function to produce an iterator
|
|
// `next()`. Calling `stop()` on a routine will conclude processing of all
|
|
// sent events and produce `final()` event representing the terminal state.
|
|
type Routine struct {
|
|
name string
|
|
handle handleFunc
|
|
queue *queue.PriorityQueue
|
|
history []Event
|
|
out chan Event
|
|
fin chan error
|
|
rdy chan struct{}
|
|
running *uint32
|
|
logger log.Logger
|
|
metrics *Metrics
|
|
}
|
|
|
|
func newRoutine(name string, handleFunc handleFunc, bufferSize int) *Routine {
|
|
return &Routine{
|
|
name: name,
|
|
handle: handleFunc,
|
|
queue: queue.NewPriorityQueue(bufferSize, true),
|
|
history: make([]Event, 0, historySize),
|
|
out: make(chan Event, bufferSize),
|
|
rdy: make(chan struct{}, 1),
|
|
fin: make(chan error, 1),
|
|
running: new(uint32),
|
|
logger: log.NewNopLogger(),
|
|
metrics: NopMetrics(),
|
|
}
|
|
}
|
|
|
|
func (rt *Routine) setLogger(logger log.Logger) {
|
|
rt.logger = logger
|
|
}
|
|
|
|
// nolint:unused
|
|
func (rt *Routine) setMetrics(metrics *Metrics) {
|
|
rt.metrics = metrics
|
|
}
|
|
|
|
func (rt *Routine) start() {
|
|
rt.logger.Info(fmt.Sprintf("%s: run", rt.name))
|
|
running := atomic.CompareAndSwapUint32(rt.running, uint32(0), uint32(1))
|
|
if !running {
|
|
panic(fmt.Sprintf("%s is already running", rt.name))
|
|
}
|
|
close(rt.rdy)
|
|
defer func() {
|
|
if r := recover(); r != nil {
|
|
var (
|
|
b strings.Builder
|
|
j int
|
|
)
|
|
for i := len(rt.history) - 1; i >= 0; i-- {
|
|
fmt.Fprintf(&b, "%d: %+v\n", j, rt.history[i])
|
|
j++
|
|
}
|
|
panic(fmt.Sprintf("%v\nlast events:\n%v", r, b.String()))
|
|
}
|
|
stopped := atomic.CompareAndSwapUint32(rt.running, uint32(1), uint32(0))
|
|
if !stopped {
|
|
panic(fmt.Sprintf("%s is failed to stop", rt.name))
|
|
}
|
|
}()
|
|
|
|
for {
|
|
events, err := rt.queue.Get(1)
|
|
if err == queue.ErrDisposed {
|
|
rt.terminate(nil)
|
|
return
|
|
} else if err != nil {
|
|
rt.terminate(err)
|
|
return
|
|
}
|
|
oEvent, err := rt.handle(events[0].(Event))
|
|
rt.metrics.EventsHandled.With("routine", rt.name).Add(1)
|
|
if err != nil {
|
|
rt.terminate(err)
|
|
return
|
|
}
|
|
rt.metrics.EventsOut.With("routine", rt.name).Add(1)
|
|
rt.logger.Debug(fmt.Sprintf("%s: produced %T %+v", rt.name, oEvent, oEvent))
|
|
|
|
// Skip rTrySchedule and rProcessBlock events as they clutter the history
|
|
// due to their frequency.
|
|
switch events[0].(type) {
|
|
case rTrySchedule:
|
|
case rProcessBlock:
|
|
default:
|
|
rt.history = append(rt.history, events[0].(Event))
|
|
if len(rt.history) > historySize {
|
|
rt.history = rt.history[1:]
|
|
}
|
|
}
|
|
|
|
rt.out <- oEvent
|
|
}
|
|
}
|
|
|
|
// XXX: look into returning OpError in the net package
|
|
func (rt *Routine) send(event Event) bool {
|
|
rt.logger.Debug(fmt.Sprintf("%s: received %T %+v", rt.name, event, event))
|
|
if !rt.isRunning() {
|
|
return false
|
|
}
|
|
err := rt.queue.Put(event)
|
|
if err != nil {
|
|
rt.metrics.EventsShed.With("routine", rt.name).Add(1)
|
|
rt.logger.Error(fmt.Sprintf("%s: send failed, queue was full/stopped", rt.name))
|
|
return false
|
|
}
|
|
|
|
rt.metrics.EventsSent.With("routine", rt.name).Add(1)
|
|
return true
|
|
}
|
|
|
|
func (rt *Routine) isRunning() bool {
|
|
return atomic.LoadUint32(rt.running) == 1
|
|
}
|
|
|
|
func (rt *Routine) next() chan Event {
|
|
return rt.out
|
|
}
|
|
|
|
func (rt *Routine) ready() chan struct{} {
|
|
return rt.rdy
|
|
}
|
|
|
|
func (rt *Routine) stop() {
|
|
if !rt.isRunning() { // XXX: this should check rt.queue.Disposed()
|
|
return
|
|
}
|
|
|
|
rt.logger.Info(fmt.Sprintf("%s: stop", rt.name))
|
|
rt.queue.Dispose() // this should block until all queue items are free?
|
|
}
|
|
|
|
func (rt *Routine) final() chan error {
|
|
return rt.fin
|
|
}
|
|
|
|
// XXX: Maybe get rid of this
|
|
func (rt *Routine) terminate(reason error) {
|
|
// We don't close the rt.out channel here, to avoid spinning on the closed channel
|
|
// in the event loop.
|
|
rt.fin <- reason
|
|
}
|