oxmox
7063e2102e
git-subtree-dir: external/nng git-subtree-split: 29b73962b939a6fbbf6ea8d5d7680bb06d0eeb99
62 lines
1.4 KiB
Text
62 lines
1.4 KiB
Text
= PubSub Forwarder
|
|
|
|
This is a trivial example of a forwarder/proxy for the pub/sub pattern.
|
|
|
|
The concept is as follows: the forwarder will listen for connections on
|
|
both a front-end port and a back-end port. The front-end will act as a
|
|
subscriber so that publishers can publish to it. The back-end will act
|
|
as a publisher so that subscribers can subscribe to it. The front-end
|
|
then forwards to the back end.
|
|
|
|
== Compiling
|
|
|
|
CMake with ninja-build is simplest:
|
|
|
|
[source, bash]
|
|
----
|
|
cmake -GNinja -B build
|
|
cd build
|
|
ninja
|
|
----
|
|
|
|
Or if you prefer a traditional approach,
|
|
the following is an example typical of UNIX and similar systems like
|
|
Linux and macOS may appeal:
|
|
|
|
[source, bash]
|
|
----
|
|
export CPPFLAGS="-I /usr/local/include"
|
|
export LDFLAGS="-L /usr/local/lib -lnng"
|
|
export CC="cc"
|
|
${CC} ${CPPFLAGS} pubsub_forwarder.c -o pubsub_forwarder ${LDFLAGS}
|
|
----
|
|
|
|
== Running
|
|
|
|
An example setup for running this example would involve the following:
|
|
|
|
. Step 1: Run this example binary (in the background or a terminal, etc)
|
|
. Step 2: In a new terminal, run the following
|
|
|
|
[source, bash]
|
|
----
|
|
nngcat --sub --dial "tcp://localhost:3328" --quoted
|
|
----
|
|
|
|
. Step 3: In a second terminal, run the same command again to give us two subscribers
|
|
|
|
[source, bash]
|
|
----
|
|
nngcat --sub --dial "tcp://localhost:3328" --quoted
|
|
----
|
|
|
|
|
|
. In a third terminal, run the following to publish a counter
|
|
|
|
[source, bash]
|
|
----
|
|
for n in $(seq 0 99); do nngcat --pub --dial "tcp://localhost:3327" --data "$n"; done
|
|
----
|
|
|
|
|
|
|