Generic example publish does not work on 1.28.0 go client

[boskiv]

I have run nats server, from docker and local
With 1.28.0 message does not publish to subject

package main

import (
	"github.com/nats-io/nats.go"
	"github.com/sirupsen/logrus"
)

func main() {
	// Connect to a server
	nc, err := nats.Connect(nats.DefaultURL)
	if err != nil {
		logrus.WithError(err).Error("Error connecting")
	}

	// Simple Publisher
	err = nc.Publish("foo", []byte("Hello World"))
	if err != nil {
		logrus.WithError(err).Error("Error publishing")
	}
}

With NATS Cli (1.19.0) it is working well

[32654] 2023/08/13 12:45:01.770872 [TRC] [::1]:49491 - cid:27 - <<- [CONNECT {"verbose":false,"pedantic":false,"user":"crypto","pass":"[REDACTED]","tls_required":false,"name":"NATS CLI Version 0.0.35","lang":"go","version":"1.19.0","protocol":1,"echo":true,"headers":true,"no_responders":true}]
[32654] 2023/08/13 12:45:01.770905 [TRC] [::1]:49491 - cid:27 - <<- [PING]
[32654] 2023/08/13 12:45:01.770908 [TRC] [::1]:49491 - cid:27 - ->> [PONG]
[32654] 2023/08/13 12:45:01.771155 [TRC] [::1]:49491 - cid:27 - <<- [PUB chainup.reg 3]
[32654] 2023/08/13 12:45:01.771162 [TRC] [::1]:49491 - cid:27 - <<- MSG_PAYLOAD: ["asd"]
[32654] 2023/08/13 12:45:01.771184 [TRC] 127.0.0.1:64251 - cid:5 - ->> [MSG chainup.reg 1 3]
[32654] 2023/08/13 12:45:01.771198 [TRC] [::1]:49491 - cid:27 - <<- [PING]
[32654] 2023/08/13 12:45:01.771200 [TRC] [::1]:49491 - cid:27 - ->> [PONG]
[32654] 2023/08/13 12:45:01.771350 [DBG] [::1]:49491 - cid:27 - Client connection closed: Client Closed
[32654] 2023/08/13 12:45:13.151909 [TRC] 127.0.0.1:64250 - cid:4 - <<- [PING]
[32654] 2023/08/13 12:45:13.151949 [TRC] 127.0.0.1:64250 - cid:4 - ->> [PONG]
[32654] 2023/08/13 12:45:13.280175 [TRC] 127.0.0.1:64251 - cid:5 - <<- [PING]
[32654] 2023/08/13 12:45:13.280244 [TRC] 127.0.0.1:64251 - cid:5 - ->> [PONG]
[32654] 2023/08/13 12:45:15.444129 [DBG] 127.0.0.1:64250 - cid:4 - Client Ping Timer
[32654] 2023/08/13 12:45:15.444157 [DBG] 127.0.0.1:64250 - cid:4 - Delaying PING due to remote client data or ping 2s ago
[32654] 2023/08/13 12:45:15.619884 [DBG] 127.0.0.1:64251 - cid:5 - Client Ping Timer
[32654] 2023/08/13 12:45:15.619911 [DBG] 127.0.0.1:64251 - cid:5 - Delaying PING due to remote client data or ping 2s ago
[32654] 2023/08/13 12:45:19.822880 [DBG] 127.0.0.1:49553 - cid:28 - Client connection created
[32654] 2023/08/13 12:45:19.824937 [TRC] 127.0.0.1:49553 - cid:28 - <<- [CONNECT {"verbose":false,"pedantic":false,"tls_required":false,"name":"","lang":"go","version":"1.28.0","protocol":1,"echo":true,"headers":true,"no_responders":true}]
[32654] 2023/08/13 12:45:19.825588 [TRC] 127.0.0.1:49553 - cid:28 - <<- [PING]
[32654] 2023/08/13 12:45:19.825600 [TRC] 127.0.0.1:49553 - cid:28 - ->> [PONG]
[32654] 2023/08/13 12:45:19.826864 [DBG] 127.0.0.1:49553 - cid:28 - Client connection closed: Client Closed

[boskiv]

When I downgrade to 1.27.1 it comes ones and after did not come

[32654] 2023/08/13 12:49:59.743775 [TRC] 127.0.0.1:50526 - cid:29 - <<- [CONNECT {"verbose":false,"pedantic":false,"tls_required":false,"name":"","lang":"go","version":"1.27.1","protocol":1,"echo":true,"headers":true,"no_responders":true}]
[32654] 2023/08/13 12:49:59.744991 [TRC] 127.0.0.1:50526 - cid:29 - <<- [PING]
[32654] 2023/08/13 12:49:59.745011 [TRC] 127.0.0.1:50526 - cid:29 - ->> [PONG]
[32654] 2023/08/13 12:49:59.745903 [TRC] 127.0.0.1:50526 - cid:29 - <<- [PUB foo 11]
[32654] 2023/08/13 12:49:59.745917 [TRC] 127.0.0.1:50526 - cid:29 - <<- MSG_PAYLOAD: ["Hello World"]
[32654] 2023/08/13 12:49:59.746022 [TRC] 127.0.0.1:64250 - cid:4 - ->> [MSG foo 1 11]
[32654] 2023/08/13 12:49:59.747296 [DBG] 127.0.0.1:50526 - cid:29 - Client connection closed: Client Closed
[32654] 2023/08/13 12:50:02.744178 [DBG] 127.0.0.1:50540 - cid:30 - Client connection created
[32654] 2023/08/13 12:50:02.744620 [TRC] 127.0.0.1:50540 - cid:30 - <<- [CONNECT {"verbose":false,"pedantic":false,"tls_required":false,"name":"","lang":"go","version":"1.27.1","protocol":1,"echo":true,"headers":true,"no_responders":true}]
[32654] 2023/08/13 12:50:02.744665 [TRC] 127.0.0.1:50540 - cid:30 - <<- [PING]
[32654] 2023/08/13 12:50:02.744671 [TRC] 127.0.0.1:50540 - cid:30 - ->> [PONG]
[32654] 2023/08/13 12:50:02.745276 [DBG] 127.0.0.1:50540 - cid:30 - Client connection closed: Client Closed
[32654] 2023/08/13 12:50:07.182003 [DBG] 127.0.0.1:50554 - cid:31 - Client connection created
[32654] 2023/08/13 12:50:07.183418 [TRC] 127.0.0.1:50554 - cid:31 - <<- [CONNECT {"verbose":false,"pedantic":false,"tls_required":false,"name":"","lang":"go","version":"1.27.1","protocol":1,"echo":true,"headers":true,"no_responders":true}]
[32654] 2023/08/13 12:50:07.183531 [TRC] 127.0.0.1:50554 - cid:31 - <<- [PING]
[32654] 2023/08/13 12:50:07.183539 [TRC] 127.0.0.1:50554 - cid:31 - ->> [PONG]
[32654] 2023/08/13 12:50:07.184085 [DBG] 127.0.0.1:50554 - cid:31 - Client connection closed: Client Closed
[32654] 2023/08/13 12:50:10.560299 [DBG] 127.0.0.1:50568 - cid:32 - Client connection created
[32654] 2023/08/13 12:50:10.562093 [TRC] 127.0.0.1:50568 - cid:32 - <<- [CONNECT {"verbose":false,"pedantic":false,"tls_required":false,"name":"","lang":"go","version":"1.27.1","protocol":1,"echo":true,"headers":true,"no_responders":true}]
[32654] 2023/08/13 12:50:10.562187 [TRC] 127.0.0.1:50568 - cid:32 - <<- [PING]
[32654] 2023/08/13 12:50:10.562193 [TRC] 127.0.0.1:50568 - cid:32 - ->> [PONG]
[32654] 2023/08/13 12:50:10.562815 [DBG] 127.0.0.1:50568 - cid:32 - Client connection closed: Client Closed

I have no deduplication jetstream enabled. Is there something else I can check ?

[Jarema]

The client probably closes before the message is send to the server.

To ensure consistent behavior in such short living app, it's good to call

nc.Flush()

before closing it.

as showed in example: https://github.com/nats-io/nats.go/blob/main/examples/nats-pub/main.go

Without it, client might, or might not manage to flush the buffered messages in time.

EDIT: It is core NATS, so it has nothing to do with JetStream.