19e2ffe37e
This release breaks API and ABI by making use of library way easier and more safe. No app in a nuttx tree uses psmq, so nothing in-tree will be broken by this change. Updated license files to Apache 2.0. Tested on nucleo-f091 Signed-off-by: Michał Łyszczek <michal.lyszczek@bofc.pl>
1.7 KiB
1.7 KiB
System / psmq Publish Subscribe Message Queue
psmq is publish subscribe message queue. It's a set of programs and libraries
to implement publish/subscribe way of inter-process communication on top of
POSIX message queue.
Manuals, source code and more info at: https://psmq.bofc.pl
Little demo using psmqd broker, psmq_pub and psmq_sub:
Start broker and make it log to file
nsh> psmqd -b/brok -p/sd/psmqd/psmqd.log &
Start subscribe thread that will read all messages send on /can/* and
/adc/* topic, and dump all readings to file
nsh> psmq_sub -n/sub -b/brok -t/can/* -t/adc/* -o/sd/psmq-sub/can.log &
n/connected to broker /brok
n/subscribed to: /can/*
n/subscribed to: /adc/*
n/start receiving data
n/reply timeout set 100
Publish some messages
nsh> psmq_pub -b/brok -t/can/engine/rpm -m50
nsh> psmq_pub -b/brok -t/adc/volt -m30
nsh> psmq_pub -b/brok -t/can/room/10/temp -m23
nsh> psmq_pub -b/brok -t/pwm/fan1/speed -m300
Check out subscribe thread logs
nsh> cat /sd/psmq-sub/can.log
[2021-05-23 17:53:59] p:0 l: 3 /can/engine/rpm 50
[2021-05-23 17:53:59] p:0 l: 3 /adc/volt 30
[2021-05-23 17:53:59] p:0 l: 3 /can/room/10/temp 23
As you can see /pwm/fan1/speed hasn't been received by subscribe thread,
since we didn't subscribe to it.
Content:
psmqd– broker, relays messages between clients.psmq_sub– listens to specified topics, can be used as logger for communication (optional).psmq_pub– publishes messages directly from shell. Can send binary data, but requires pipes, so on nuttx it can only send ASCII.libpsmq– library used to communicate with the broker and send/receive messages.