term/event/nats/nats.go

126 lines
2.8 KiB
Go

package nats
import (
"context"
"encoding/json"
"fmt"
nats "github.com/nats-io/nats.go"
"github.com/nats-io/nats.go/jetstream"
geEvent "github.com/grassrootseconomics/eth-tracker/pkg/event"
"git.defalsify.org/vise.git/logging"
"git.defalsify.org/vise.git/db"
"git.grassecon.net/urdt/ussd/common"
"git.grassecon.net/term/event"
"git.grassecon.net/term/config"
)
var (
logg = logging.NewVanilla().WithDomain("term-nats")
)
type NatsSubscription struct {
event.Router
ctx context.Context
conn *nats.Conn
js jetstream.JetStream
cs jetstream.Consumer
cctx jetstream.ConsumeContext
}
func NewNatsSubscription(store db.Db) *NatsSubscription {
return &NatsSubscription{
Router: event.Router{
Store: &common.UserDataStore{
Db: store,
},
},
}
}
func toServerInfo(conn *nats.Conn) string {
return fmt.Sprintf("%s@%s (v%s)", conn.ConnectedServerName(), conn.ConnectedUrlRedacted(), conn.ConnectedServerVersion())
}
func disconnectHandler(conn *nats.Conn, err error) {
logg.Errorf("nats disconnected", "status", conn.Status(), "reconnects", conn.Stats().Reconnects, "err", err)
}
func reconnectHandler(conn *nats.Conn) {
serverInfo := toServerInfo(conn)
logg.Errorf("nats reconnected", "status", conn.Status(), "reconnects", conn.Stats().Reconnects, "server", serverInfo)
}
func(n *NatsSubscription) Connect(ctx context.Context, connStr string) error {
var err error
n.conn, err = nats.Connect(connStr)
if err != nil {
return err
}
n.conn.SetDisconnectErrHandler(disconnectHandler)
n.conn.SetReconnectHandler(reconnectHandler)
n.js, err = jetstream.New(n.conn)
if err != nil {
return err
}
n.cs, err = n.js.CreateConsumer(ctx, "TRACKER", jetstream.ConsumerConfig{
Name: config.JetstreamClientName,
Durable: config.JetstreamClientName,
FilterSubjects: []string{"TRACKER.*"},
})
if err != nil {
return err
}
serverInfo := toServerInfo(n.conn)
logg.DebugCtxf(ctx, "nats connected, starting consumer", "status", n.conn.Status(), "server", serverInfo)
n.ctx = ctx
n.cctx, err = n.cs.Consume(n.handleEvent)
if err != nil {
return err
}
return nil
}
func(n *NatsSubscription) Close() error {
n.cctx.Stop()
select {
case <-n.cctx.Closed():
n.conn.Close()
}
return nil
}
func fail(m jetstream.Msg) {
err := m.Nak()
if err != nil {
logg.Errorf("nats nak fail", "err", err)
}
}
func(n *NatsSubscription) handleEvent(m jetstream.Msg) {
var ev geEvent.Event
logg.DebugCtxf(n.ctx, "have msg", "err", m)
b := m.Data()
err := json.Unmarshal(b, &ev)
if err != nil {
logg.ErrorCtxf(n.ctx, "nats msg deserialize fail", "err", err)
//fail(m)
} else {
err = n.Route(n.ctx, &ev)
if err != nil {
logg.ErrorCtxf(n.ctx, "handler route fail", "err", err)
//fail(m)
}
}
err = m.Ack()
if err != nil {
logg.ErrorCtxf(n.ctx, "ack fail", "err", err)
panic("ack fail")
}
logg.DebugCtxf(n.ctx, "handle msg complete")
}