mirror of https://github.com/hashicorp/consul
110 lines
2.8 KiB
Go
110 lines
2.8 KiB
Go
package submatview
|
|
|
|
import (
|
|
"context"
|
|
"errors"
|
|
|
|
"github.com/hashicorp/consul/acl"
|
|
"github.com/hashicorp/consul/agent/consul/state"
|
|
"github.com/hashicorp/consul/agent/consul/stream"
|
|
"github.com/hashicorp/consul/lib/retry"
|
|
"github.com/hashicorp/consul/proto/pbsubscribe"
|
|
)
|
|
|
|
// LocalMaterializer is a materializer for a stream of events
|
|
// and manages the local subscription to the event publisher
|
|
// until the cache result is discarded when its TTL expires.
|
|
type LocalMaterializer struct {
|
|
deps Deps
|
|
backend LocalBackend
|
|
retryWaiter *retry.Waiter
|
|
handler eventHandler
|
|
|
|
mat *materializer
|
|
}
|
|
|
|
var _ Materializer = (*LocalMaterializer)(nil)
|
|
|
|
type LocalBackend interface {
|
|
Subscribe(req *stream.SubscribeRequest) (*stream.Subscription, error)
|
|
}
|
|
|
|
func NewLocalMaterializer(backend LocalBackend, deps Deps) *LocalMaterializer {
|
|
m := LocalMaterializer{
|
|
backend: backend,
|
|
deps: deps,
|
|
mat: newMaterializer(deps.Logger, deps.View, deps.Waiter),
|
|
}
|
|
return &m
|
|
}
|
|
|
|
// Query implements Materializer
|
|
func (m *LocalMaterializer) Query(ctx context.Context, minIndex uint64) (Result, error) {
|
|
return m.mat.query(ctx, minIndex)
|
|
}
|
|
|
|
// Run receives events from a local subscription backend and sends them to the View.
|
|
// It runs until ctx is cancelled, so it is expected to be run in a goroutine.
|
|
// Mirrors implementation of RPCMaterializer.
|
|
//
|
|
// Run implements Materializer
|
|
func (m *LocalMaterializer) Run(ctx context.Context) {
|
|
for {
|
|
req := m.deps.Request(m.mat.currentIndex())
|
|
err := m.subscribeOnce(ctx, req)
|
|
if ctx.Err() != nil {
|
|
return
|
|
}
|
|
m.mat.handleError(req, err)
|
|
|
|
if err := m.mat.retryWaiter.Wait(ctx); err != nil {
|
|
return
|
|
}
|
|
}
|
|
}
|
|
|
|
// subscribeOnce opens a new subscription to a local backend and runs
|
|
// for its lifetime or until the view is closed.
|
|
func (m *LocalMaterializer) subscribeOnce(ctx context.Context, req *pbsubscribe.SubscribeRequest) error {
|
|
ctx, cancel := context.WithCancel(ctx)
|
|
defer cancel()
|
|
|
|
m.handler = initialHandler(req.Index)
|
|
|
|
entMeta := acl.NewEnterpriseMetaWithPartition(req.Partition, req.Namespace)
|
|
sub, err := m.backend.Subscribe(state.PBToStreamSubscribeRequest(req, entMeta))
|
|
if err != nil {
|
|
return err
|
|
}
|
|
defer sub.Unsubscribe()
|
|
|
|
for {
|
|
event, err := sub.Next(ctx)
|
|
switch {
|
|
case errors.Is(err, stream.ErrSubForceClosed):
|
|
m.deps.Logger.Trace("subscription reset by server")
|
|
return err
|
|
|
|
case err != nil:
|
|
return err
|
|
}
|
|
|
|
e := event.Payload.ToSubscriptionEvent(event.Index)
|
|
m.handler, err = m.handler(m, e)
|
|
if err != nil {
|
|
m.mat.reset()
|
|
return err
|
|
}
|
|
}
|
|
}
|
|
|
|
// updateView implements viewState
|
|
func (m *LocalMaterializer) updateView(events []*pbsubscribe.Event, index uint64) error {
|
|
return m.mat.updateView(events, index)
|
|
}
|
|
|
|
// reset implements viewState
|
|
func (m *LocalMaterializer) reset() {
|
|
m.mat.reset()
|
|
}
|