You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
112 lines
3.6 KiB
112 lines
3.6 KiB
package core
|
|
|
|
import (
|
|
"context"
|
|
"fmt"
|
|
"time"
|
|
|
|
tmpubsub "github.com/tendermint/tendermint/libs/pubsub"
|
|
tmquery "github.com/tendermint/tendermint/libs/pubsub/query"
|
|
ctypes "github.com/tendermint/tendermint/rpc/core/types"
|
|
rpctypes "github.com/tendermint/tendermint/rpc/jsonrpc/types"
|
|
)
|
|
|
|
const (
|
|
// Buffer on the Tendermint (server) side to allow some slowness in clients.
|
|
subBufferSize = 100
|
|
)
|
|
|
|
// Subscribe for events via WebSocket.
|
|
// More: https://docs.tendermint.com/master/rpc/#/Websocket/subscribe
|
|
func Subscribe(ctx *rpctypes.Context, query string) (*ctypes.ResultSubscribe, error) {
|
|
addr := ctx.RemoteAddr()
|
|
|
|
if env.EventBus.NumClients() >= env.Config.MaxSubscriptionClients {
|
|
return nil, fmt.Errorf("max_subscription_clients %d reached", env.Config.MaxSubscriptionClients)
|
|
} else if env.EventBus.NumClientSubscriptions(addr) >= env.Config.MaxSubscriptionsPerClient {
|
|
return nil, fmt.Errorf("max_subscriptions_per_client %d reached", env.Config.MaxSubscriptionsPerClient)
|
|
}
|
|
|
|
env.Logger.Info("Subscribe to query", "remote", addr, "query", query)
|
|
|
|
q, err := tmquery.New(query)
|
|
if err != nil {
|
|
return nil, fmt.Errorf("failed to parse query: %w", err)
|
|
}
|
|
|
|
subCtx, cancel := context.WithTimeout(ctx.Context(), SubscribeTimeout)
|
|
defer cancel()
|
|
|
|
sub, err := env.EventBus.Subscribe(subCtx, addr, q, subBufferSize)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
// Capture the current ID, since it can change in the future.
|
|
subscriptionID := ctx.JSONReq.ID
|
|
go func() {
|
|
for {
|
|
select {
|
|
case msg := <-sub.Out():
|
|
var (
|
|
resultEvent = &ctypes.ResultEvent{Query: query, Data: msg.Data(), Events: msg.Events()}
|
|
resp = rpctypes.NewRPCSuccessResponse(subscriptionID, resultEvent)
|
|
)
|
|
writeCtx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
|
|
defer cancel()
|
|
if err := ctx.WSConn.WriteRPCResponse(writeCtx, resp); err != nil {
|
|
env.Logger.Info("Can't write response (slow client)",
|
|
"to", addr, "subscriptionID", subscriptionID, "err", err)
|
|
}
|
|
case <-sub.Canceled():
|
|
if sub.Err() != tmpubsub.ErrUnsubscribed {
|
|
var reason string
|
|
if sub.Err() == nil {
|
|
reason = "Tendermint exited"
|
|
} else {
|
|
reason = sub.Err().Error()
|
|
}
|
|
var (
|
|
err = fmt.Errorf("subscription was canceled (reason: %s)", reason)
|
|
resp = rpctypes.RPCServerError(subscriptionID, err)
|
|
)
|
|
if ok := ctx.WSConn.TryWriteRPCResponse(resp); !ok {
|
|
env.Logger.Info("Can't write response (slow client)",
|
|
"to", addr, "subscriptionID", subscriptionID, "err", err)
|
|
}
|
|
}
|
|
return
|
|
}
|
|
}
|
|
}()
|
|
|
|
return &ctypes.ResultSubscribe{}, nil
|
|
}
|
|
|
|
// Unsubscribe from events via WebSocket.
|
|
// More: https://docs.tendermint.com/master/rpc/#/Websocket/unsubscribe
|
|
func Unsubscribe(ctx *rpctypes.Context, query string) (*ctypes.ResultUnsubscribe, error) {
|
|
addr := ctx.RemoteAddr()
|
|
env.Logger.Info("Unsubscribe from query", "remote", addr, "query", query)
|
|
q, err := tmquery.New(query)
|
|
if err != nil {
|
|
return nil, fmt.Errorf("failed to parse query: %w", err)
|
|
}
|
|
err = env.EventBus.Unsubscribe(context.Background(), addr, q)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return &ctypes.ResultUnsubscribe{}, nil
|
|
}
|
|
|
|
// UnsubscribeAll from all events via WebSocket.
|
|
// More: https://docs.tendermint.com/master/rpc/#/Websocket/unsubscribe_all
|
|
func UnsubscribeAll(ctx *rpctypes.Context) (*ctypes.ResultUnsubscribe, error) {
|
|
addr := ctx.RemoteAddr()
|
|
env.Logger.Info("Unsubscribe from all", "remote", addr)
|
|
err := env.EventBus.UnsubscribeAll(context.Background(), addr)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return &ctypes.ResultUnsubscribe{}, nil
|
|
}
|