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