(draft)=

# Working with libzmq DRAFT sockets

libzmq-4.2 has introduced the concept of unstable DRAFT APIs.
As of libzmq-4.2, this includes the CLIENT-SERVER and RADIO-DISH patterns.

Because these APIs are explicitly unstable,
pyzmq does not support them by default,
and pyzmq binaries (wheels) will not be built with DRAFT API support.
However, pyzmq-17 can be built with draft socket support,
as long as you compile pyzmq yourself with a special flag.

To install libzmq with draft support:

```bash
ZMQ_VERSION=4.3.4
PREFIX=/usr/local
CPU_COUNT=${CPU_COUNT:-$(python3 -c "import os; print(os.cpu_count())")}


wget https://github.com/zeromq/libzmq/releases/download/v${ZMQ_VERSION}/zeromq-${ZMQ_VERSION}.tar.gz -O libzmq.tar.gz
tar -xzf libzmq.tar.gz
cd zeromq-${ZMQ_VERSION}
./configure --prefix=${PREFIX} --enable-drafts
make -j${CPU_COUNT} && make install
```

And to install pyzmq with draft support:

```bash
export ZMQ_PREFIX=${PREFIX}
export ZMQ_DRAFT_API=1
pip install -v --no-binary pyzmq --pre pyzmq
```

By specifying `--no-binary pyzmq`, pip knows to not install wheels, and will compile pyzmq from source.

The `ZMQ_PREFIX=$PREFIX` part is only necessary if libzmq is installed somewhere not on the default search path.
If libzmq is installed in {file}`/usr/local` or similar,
only the `ZMQ_ENABLE_DRAFTS` option is required.

There are examples of the CLIENT-SERVER and RADIO-DISH patterns in the {file}`examples/draft`
directory of the pyzmq repository.