WAMP_POCO is a fork of AutobahnCpp that is using POCO instead of Boost. JSON is used for serialization and the transport is WebSocket (optionally via SSL). Errors are raised by std::future exceptions. Authentication with "ticket" and "wampcra" methods is implemented.
- Modern C++ compiler (MSVC 2013 and GCC 4.7 tested)
- POCO Libraries (1.5.3+ for WAMP-CRA support)
- openssl (required by POCO's Net_SSL module)
Notable changes to AutobahnCpp:
- Using std::future instead of boost::future. The missing "then" continuation functionality is implemented in util/Continuation.h.
future.then([]{ ... });
can be rewritten toutil::then(future, []{ ... });
- Using Poco::Dynamic instead of boost any libraries. See documentation for usage
For a complete compilable example see the directory examples_poco
.
The examples in this repository are not updated for this fork. The changes would be trivial as demonstrated in the following.
Calling a remote Procedure
auto c1 = util::then(session.call("com.mathservice.add2", {23, 777}),
[&](std::future<any> f) {
cout << "Got call result " << f.get().convert<uint64_t>() << endl;
});
Registering a remoted Procedure
auto r1 = util::then(session.provide("com.myapp.cpp.square",
[](const anyvec& args, const anymap& kwargs) {
cout << "Procedure is invoked .." << endl;
uint64_t x = args[0].convert<uint64_t>();
return x * x;
}),
[](future<registration> reg) {
cout << "Registered with ID " << reg.get().id << endl;
});
Publishing an Event
session.publish("com.myapp.topic2", {23, true, string("hello")});
Publishing an Event (acknowledged)
auto opts = PublishOptions();
opts.acknowledge = True;
auto p1 = util::then(session.publish("com.myapp.topic2", {23, true, string("hello")}, opts),
[](future<publication> pub) {
cout << "Published with ID " << pub.get().id << endl;
});
Subscribing to a Topic
auto s1 = util::then(session.subscribe("com.myapp.topic1",
[](const anyvec& args, const anymap& kwargs) {
cout << "Got event: " << args[0].convert<uint64_t>() << endl;
}),
[](future<subscription> sub) {
cout << "Subscribed with ID " << sub.get().id << endl;
});
Autobahn|Cpp is a subproject of Autobahn which implements the Web Application Messaging Protocol (WAMP) in C++ supporting the following application roles
- Caller
- Callee
- Publisher
- Subscriber
The API and implementation make use of modern C++ 11 and new asynchronous idioms using (upcoming) features of the standard C++ library, in particular Futures, Continuations and Lambdas.
Continuations are one way of managing control flow in an asynchronous program. Other styles include: asynchronous Callbacks, Coroutines (
yield
orawait
), Actors (Erlang/OTP, Scala/Akka or Rust) and Transactional memory.
Autobahn|Cpp supports running WAMP (rawsocket-msgpack
) over TCP(-TLS), Unix domain sockets or pipes (stdio
). The library is "header-only", light-weight (< 2k code lines) and depends on the following:
- C++ 11 compiler
boost::future
boost::any
boost::asio
For getting help, questions or feedback, get in touch on the mailing list, Twitter or IRC #autobahn
(Freenode).
Here is how programming with C++ and Autobahn|Cpp looks like.
Calling a remote Procedure
auto c1 = session.call("com.mathservice.add2", {23, 777})
.then(
[&](future<any> f) {
cout << "Got call result " << any_cast<uint64_t> (f.get()) << endl;
});
Registering a remoted Procedure
auto r1 = session.provide("com.myapp.cpp.square",
[](const anyvec& args, const anymap& kwargs) {
cout << "Procedure is invoked .." << endl;
uint64_t x = any_cast<uint64_t> (args[0]);
return x * x;
})
.then(
[](future<registration> reg) {
cout << "Registered with ID " << reg.get().id << endl;
});
Publishing an Event
session.publish("com.myapp.topic2", {23, true, string("hello")});
Publishing an Event (acknowledged)
auto opts = PublishOptions();
opts.acknowledge = True;
auto p1 = session.publish("com.myapp.topic2", {23, true, string("hello")}, opts)
.then(
[](future<publication> pub) {
cout << "Published with ID " << pub.get().id << endl;
});
Subscribing to a Topic
auto s1 = session.subscribe("com.myapp.topic1",
[](const anyvec& args, const anymap& kwargs) {
cout << "Got event: " << any_cast<uint64_t>(args[0]) << endl;
})
.then(
[](future<subscription> sub) {
cout << "Subscribed with ID " << sub.get().id << endl;
});
Here is JavaScript running in Chrome call into C++ running on command line. Both are connected via a WAMP router, in this case Autobahn|Python based.
Notes
- The library code is written in standard C++ 11. Target toolchains currently include clang and gcc. Support for MSVC is tracked on this issue.
- While C++ 11 includes
std::future
in the standard library, this lacks continuations.boost::future.then
allows attaching continuations to futures as outlined in the proposal here. This feature will come to standard C++, but probably not before 2015 (see C++ Standardisation Roadmap)- Support for
when_all
andwhen_any
as described in above proposal depends on Boost 1.56 (upcoming release as of 31/03/2014) or higher.- The library and example programs were tested and developed with clang 3.4, libc++ and Boost trunk/1.56 on an Ubuntu 13.10 x86-64 bit system. It also works with gcc 4.8, libstdc++ and Boost trunk/1.56. Your mileage with other versions of the former may vary, but we accept PRs;)
Install some libs and build tools:
sudo apt-get install libbz2-dev libssl-dev ruby libtool autoconf scons
sudo apt-get install clang-3.4 libc++1 libc++-dev
To build Boost 1.55 (current release) from sources, get source code package for the latest Boost release from here and
cd $HOME
tar xvjf Downloads/boost_1_55_0.tar.bz2
cd boost_1_55_0/
./bootstrap.sh
./b2 toolset=clang cxxflags="-stdlib=libc++" linkflags="-stdlib=libc++" -j 4
Note: The
-j 4
option will allow use of 4 cores for building.
To build with GCC instead of clang:
./b2 toolset=gcc -j 4
To build Boost trunk (needed for when_all
, when_any
)
cd $HOME
git clone --recursive git@github.com:boostorg/boost.git
cd boost/
./bootstrap.sh
./b2 toolset=clang cxxflags="-stdlib=libc++" linkflags="-stdlib=libc++" -j 4
Get MsgPack-C and build with clang:
cd $HOME
git clone https://github.com/msgpack/msgpack-c.git
cd msgpack-c
./bootstrap
CXX=`which clang++` CC=`which clang` CXXFLAGS="-std=c++11 -stdlib=libc++" \
LDFLAGS="-stdlib=libc++" ./configure --prefix=$HOME/msgpack_clang
make
make install
To build with GCC instead of clang:
./configure --prefix=$HOME/msgpack_gcc
To get Autobahn|Cpp library and examples, clone the repo
cd $HOME
git clone git@github.com:tavendo/AutobahnCpp.git
cd AutobahnCpp
The library is "header-only", means there isn't anything to compile or build. Just include the relevant headers.
The Autobahn|Cpp repository contains a number of examples that demonstrate all 4 basic patterns of using WAMP:
For building the examples, add the following to your ~/.profile
:
## Use clang
##
export CC='clang'
export CXX='clang++'
## Libaries (clang based)
##
export BOOST_ROOT=${HOME}/boost_trunk_clang
export LD_LIBRARY_PATH=${BOOST_ROOT}/stage/lib:${LD_LIBRARY_PATH}
export MSGPACK_ROOT=${HOME}/msgpack_clang
export LD_LIBRARY_PATH=${MSGPACK_ROOT}/lib:${LD_LIBRARY_PATH}
For building with GCC, use the following
## Use GNU
##
export CC='gcc'
export CXX='g++'
## Libraries (GCC based)
##
export BOOST_ROOT=${HOME}/boost_trunk_gcc
export LD_LIBRARY_PATH=${BOOST_ROOT}/stage/lib:${LD_LIBRARY_PATH}
export MSGPACK_ROOT=${HOME}/msgpack_gcc
export LD_LIBRARY_PATH=${MSGPACK_ROOT}/lib:${LD_LIBRARY_PATH}
Now build all examples:
cd autobahn/examples
scons -j 4
The examples will get built in autobahn/build/examples
.
The examples include a Autobahn|Python based WAMP router and example backend.
To run this, you need Python and pip already installed.
Then, to install Autobahn|Python
pip install autobahn[twisted]
Start the example router in a first terminal
cd autobahn/examples
python server.py
Then start one of the built C++ examples in a second terminal
cd autobahn
./build/examples/call1
Click here for the Autobahn|Cpp reference documentation.
Get in touch on IRC #autobahn
on chat.freenode.net
, follow us on Twitter or join the mailing list.
- ASIO C++11 Examples
- Using Asio with C++11
- C++17: I See a Monad in Your Future!
- Boost Thread
- Boost Issue: when_all
- Boost Issue. when_any
- Boost Issue: future fires twice
- Boost C++ 1y
- Asynchronous API in C++ and the Continuation Monad
[]
Capture nothing (or, a scorched earth strategy?)[&]
Capture any referenced variable by reference[=]
Capture any referenced variable by making a copy[=, &foo]
Capture any referenced variable by making a copy, but capture variablefoo
by reference[bar]
Capturebar
by making a copy; don't copy anything else[this]
Capture the this pointer of the enclosing class