We are writing C++ code which needs messaging. Is there a free/open-source and stable AMQP server available that has equally stable C++ client library with it. We also need
For future reference, take a look at Apache Qpid - it has a C++ client library and is very good. The problem for your use-case is that Rabbit implements AMQP 0-8 and the Qpid C++ client talks AMQP 0-10.
AMQP C++ wrapper https://github.com/akalend/amqpcpp on librabbit: https://github.com/alanxz/rabbitmq-c
AMQP can be quite complex to understand -- I suggest Using Protocol Buffers to code your communication layer, it generates both python and C++. if your needs are too complicated I would suggest ICE as it supports every programming language you can think of, and I believe it also handles the protocol buffers format.
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If you are going to use AMQP, you should look at Zero MQ. It has a C++ implementation of AMQP. However they are porting it to a pure-C implementation.
Apache QPid seems to be relevant here. There's a C++ broker/client library here.
Note that since you're programming to a protocol (AMQP), your broker/client don't have to be in the same language. e.g. I'm using Scala and C# clients talking to RabbitMQ (an Erlang broker).
For RabbitMQ, the following library is more feature rich with good documentation: https://github.com/CopernicaMarketingSoftware/AMQP-CPP
I know this is a bit late, I'm kind of in the same position as the asker.
I'm looking at IceStorm and Apache QPid per answers above.
Currently I have rabbit MQ but it's not so easy to integrate with C++.
I think if you have control over both client and server code, and you don't need AMQP "the standard" and IceStorm does what you need, and you're cool with GPL license (or ready to buy a license from zeroC) .. IceStorm seems to be the most stable and cross-language solution out there.