nats pub "subject" "body" eats stdin?

[alexbozhenko]

Observed behavior

It looks like #1356 started to eat stdin(?), even when body is specified as cli argument. See repro below.

Expected behavior

nats publish
should not eat stdin?

Server and client version

server main (2.11.6)
client 0.2.2, comparing to 0.2.3

Host environment

No response

Steps to reproduce

0.2.2 sends all messages in bash while loop

curl -fSsL "https://binaries.nats.dev/nats-io/natscli/nats@v0.2.2"  | PREFIX=. sh
# while IFS=';' read -r topic message; do ./nats pub  "$topic" "$message"; done < repro.txt 
15:24:47 Published 20 bytes to "topic.62"
15:24:47 Published 20 bytes to "topic.83"
15:24:47 Published 20 bytes to "topic.60"
15:24:47 Published 19 bytes to "topic.33"
15:24:47 Published 20 bytes to "topic.36"

0.2.3 stops at the first one:

curl -fSsL "https://binaries.nats.dev/nats-io/natscli/nats@v0.2.3"  | PREFIX=. sh
# while IFS=';' read -r topic message; do ./nats pub  "$topic" "$message"; done < repro.txt
15:25:14 Published 20 bytes to "topic.62"

Cluade correctly suggested that the command is eating stdin. When giving /dev/null to nats, it works:

# while IFS=';' read -r topic message; do  ./nats pub "$topic" "$message" < /dev/null; done < repro.txt
15:40:33 Published 20 bytes to "topic.62"
15:40:33 Published 20 bytes to "topic.83"
15:40:33 Published 20 bytes to "topic.60"
15:40:33 Published 19 bytes to "topic.33"
15:40:33 Published 20 bytes to "topic.36"

cat repro.txt

topic.62;some_sort_of_msg_338
topic.83;some_sort_of_msg_114
topic.60;some_sort_of_msg_456
topic.33;some_sort_of_msg_75
topic.36;some_sort_of_msg_349

[alexbozhenko]

This was originally reported by a customer. Here is his reproducer script

# cat  script_new.sh
#!/bin/bash

# Numero di righe da generare
NUM_RIGHE=1000

# Genera righe simulate con valori casuali
for i in $(seq 1 $NUM_RIGHE); do
    TOPIC="topic.$((RANDOM % 100))"
    MESSAGGIO="some_sort_of_msg_$((RANDOM % 1000))"
    echo "x;x;$TOPIC;$MESSAGGIO"
done | tee count_new.txt|awk -F";" '{system("./nats  pub \"" $3 "\" \"" $4 "\"")}'

It should publish 1000 messages.
It is interesting that on 0.2.3 it sends a different number of messages on each run and stops prematurely. It is probably related to eating stdin, but also interplays with awk's system() call.

On 0.2.2 it consistently sends 1000 messages.

[ripienaar]

The work done in #1356 have been pretty disruptive since the beginning, I think the right thing here is just reverting the PR