Janus WebRTC Gateway

Janus is an open source, general purpose, WebRTC gateway designed and developed by Meetecho. This version of the gateway can only be installed on Linux systems: next versions will take into account cross compilation on different environments.

For some online demos and documentations, make sure you pay the project website a visit!

To discuss Janus with us and other users, there's a Google Group called meetecho-janus that you can use. If you encounter issues, though, please submit an issue on github instead.

Dependencies

To install it, you'll need to satisfy the following dependencies:

• Jansson
• libnice
• OpenSSL (at least v1.0.1e)
• libsrtp (at least v1.5 suggested)
• usrsctp (only needed if you are interested in Data Channels)
• libmicrohttpd (only needed if you are interested in REST support for the Janus API)
• libwebsockets (only needed if you are interested in WebSockets support for the Janus API)
• cmake (only needed if you are interested in WebSockets and/or BoringSSL support, as they make use of it)
• rabbitmq-c (only needed if you are interested in RabbitMQ support for the Janus API)
• paho.mqtt.c (only needed if you are interested in MQTT support for the Janus API)
• libcurl (only needed if you are interested in the TURN REST API support)

A couple of plugins depend on a few more libraries:

• Sofia-SIP (only needed for the SIP plugin)
• libopus (only needed for the bridge plugin)
• libogg (only needed for the voicemail plugin)
• libcurl (only needed if you are interested in RTSP support in the Streaming plugin or in the sample Event Handler plugin)

Additionally, you'll need the following libraries and tools:

• GLib
• pkg-config
• gengetopt

All of those libraries are usually available on most of the most common distributions. Installing these libraries on a recent Fedora, for instance, is very simple:

yum install libmicrohttpd-devel jansson-devel libnice-devel \
   openssl-devel libsrtp-devel sofia-sip-devel glib-devel \
   opus-devel libogg-devel libcurl-devel pkgconfig gengetopt \
   libtool autoconf automake

Notice that you may have to yum install epel-release as well if you're attempting an installation on a CentOS machine instead.

On Ubuntu or Debian, it would require something like this:

aptitude install libmicrohttpd-dev libjansson-dev libnice-dev \
	libssl-dev libsrtp-dev libsofia-sip-ua-dev libglib2.0-dev \
	libopus-dev libogg-dev libcurl4-openssl-dev pkg-config gengetopt \
	libtool automake

• Note: please notice that libopus may not be available out of the box on Ubuntu or Debian, unless you're using a recent version (e.g., Ubuntu 14.04 LTS). In that case, you'll have to install it manually.

• Note: For custom installations of libnice, you can run pkg-config --cflags --libs nice to make sure Janus can find the installation. If not, you may need to set the PKG_CONFIG_PATH environment variable prior to compiling Janus, eg. export PKG_CONFIG_PATH=/path/to/libnice/lib/pkgconfig

In case you're interested in compiling the sample Event Handler plugin, you'll need to install the development version of libcurl as well (usually libcurl-devel on Fedora/CentOS, libcurl4-openssl-dev on Ubuntu/Debian).

If your distro ships a pre-1.5 version of libsrtp, you'll have to uninstall that version and install 1.5 or 2.0.0 manually. In fact, 1.4.x is known to cause several issues with WebRTC. Installation of version 1.5.4 is quite straightforward:

wget https://github.com/cisco/libsrtp/archive/v1.5.4.tar.gz
tar xfv v1.5.4.tar.gz
cd libsrtp-1.5.4
./configure --prefix=/usr --enable-openssl
make shared_library && sudo make install

The instructions for version 2.0.0 is practically the same:

wget https://github.com/cisco/libsrtp/archive/v2.0.0.tar.gz
tar xfv v2.0.0.tar.gz
cd libsrtp-2.0.0
./configure --prefix=/usr --enable-openssl
make shared_library && sudo make install

The Janus configure script autodetects which one you have installed and links to the correct library automatically, choosing v2.0.0 if both are installed. If you want v1.5.4 to be picked, pass --disable-libsrtp2 when configuring Janus to force it to use the older version instead.

• Note: when installing libsrtp, no matter which version, you may need to pass --libdir=/usr/lib64 to the configure script if you're installing on a x86_64 distribution.

If you want to make use of BoringSSL instead of OpenSSL (e.g., because you want to take advantage of --enable-dtls-settimeout), you'll have to manually install it to a specific location. Use the following steps:

git clone https://boringssl.googlesource.com/boringssl
cd boringssl
# Don't barf on errors
sed -i s/" -Werror"//g CMakeLists.txt
# Build
mkdir -p build
cd build
cmake -DCMAKE_CXX_FLAGS="-lrt" ..
make
cd ..
# Install
sudo mkdir -p /opt/boringssl
sudo cp -R include /opt/boringssl/
sudo mkdir -p /opt/boringssl/lib
sudo cp build/ssl/libssl.a /opt/boringssl/lib/
sudo cp build/crypto/libcrypto.a /opt/boringssl/lib/

Once the library is installed, you'll have to pass an additional --enable-boringssl flag to the configure script, as by default Janus will be built assuming OpenSSL will be used. By default, Janus expects BoringSSL to be installed in /opt/boringssl -- if it's installed in another location, pass the path to the configure script as such: --enable-boringssl=/path/to/boringssl If you were using OpenSSL and want to switch to BoringSSL, make sure you also do a make clean in the Janus folder before compiling with the new BoringSSL support. If you enabled BoringSSL support and also want Janus to detect and react to DTLS timeouts with faster retransmissions, then pass --enable-dtls-settimeout to the configure script too.

For what concerns usrsctp, which is needed for Data Channels support, it is usually not available in repositories, so if you're interested in them (support is optional) you'll have to install it manually. It is a pretty easy and standard process:

git clone https://github.com/sctplab/usrsctp
cd usrsctp
./bootstrap
./configure --prefix=/usr && make && sudo make install

• Note: you may need to pass --libdir=/usr/lib64 to the configure script if you're installing on a x86_64 distribution.

The same applies for libwebsockets, which is needed for the optional WebSockets support. If you're interested in supporting WebSockets to control Janus, as an alternative (or replacement) to the default plain HTTP REST API, you'll have to install it manually:

git clone git://git.libwebsockets.org/libwebsockets
cd libwebsockets
# If you want the stable version of libwebsockets, uncomment the next line
# git checkout v1.5-chrome47-firefox41
mkdir build
cd build
cmake -DCMAKE_INSTALL_PREFIX:PATH=/usr -DCMAKE_C_FLAGS="-fpic" ..
make && sudo make install

• Note: if libwebsockets.org is unreachable for any reason, replace the first line with this:

  git clone https://github.com/warmcat/libwebsockets.git

The same applies for Eclipse Paho MQTT C client library, which is needed for the optional MQTT support. If you're interested in integrating MQTT queues as an alternative (or replacement) to HTTP and/or WebSockets to control Janus, you can install the latest version with the following steps:

git clone https://github.com/eclipse/paho.mqtt.c.git
cd paho.mqtt.c
make && sudo make install

• Note: you may want to set up a different install path for the library, to achieve that, replace the last command by 'sudo prefix=/usr make install'.

Finally, the same can be said for rabbitmq-c as well, which is needed for the optional RabbitMQ support. In fact, several different versions of the library can be found, and the versions usually available in most distribution repositories are not up-do-date with respect to the current state of the development. As such, if you're interested in integrating RabbitMQ queues as an alternative (or replacement) to HTTP and/or WebSockets to control Janus, you can install the latest version with the following steps:

git clone https://github.com/alanxz/rabbitmq-c
cd rabbitmq-c
git submodule init
git submodule update
mkdir build && cd build
cmake -DCMAKE_INSTALL_PREFIX=/usr ..
make && sudo make install

• Note: you may need to pass --libdir=/usr/lib64 to the configure script if you're installing on a x86_64 distribution.

To conclude, should you be interested in building the gateway documentation as well, you'll need some additional tools too:

• Doxygen
• Graphviz

On Fedora:

yum install doxygen graphviz

On Ubuntu/Debian:

aptitude install doxygen graphviz

Compile

Once you have installed all the dependencies, get the code:

git clone https://github.com/meetecho/janus-gateway.git
cd janus-gateway

Then just use:

sh autogen.sh

to generate the configure file. After that, configure and compile as usual to start the whole compilation process:

./configure --prefix=/opt/janus
make
make install

Since Janus requires configuration files for both the core and its modules in order to work, you'll probably also want to install the default configuration files to use, which you can do this way:

make configs

Remember to only do this once, or otherwise a subsequent make configs will overwrite any configuration file you may have modified in the meanwhile.

If you're installed the above libraries but are not interested in Data Channels, WebSockets, MQTT and/or RabbitMQ (or you don't care about any of them), you can disable them when configuring:

./configure --disable-websockets --disable-data-channels --disable-rabbitmq --disable-mqtt

If the libraries are not installed, instead, no need to manually disable them, as the configure script will skip them automatically and disable the related features by itself. A summary of what's going to be built will always appear after you do a configure, allowing you to double check if what you need and don't need is there.

If Doxygen and graphviz are available, the process can also build the documentation for you. By default the compilation process will not try to build the documentation, so if you instead prefer to build it, use the --enable-docs configuration option:

./configure --enable-docs

You can also selectively enable/disable other features (e.g., specific plugins you don't care about, or whether or not you want to build the recordings post-processor). Use the --help option when configuring for more info.

Building on MacOS

While most of the above instructions will work when compiling Janus on MacOS as well, there are a few aspects to highlight when doing that.

First of all, you can use brew to install most of the dependencies:

brew tap homebrew/boneyard
brew install jansson libnice openssl libusrsctp libmicrohttpd libwebsockets cmake rabbitmq-c sofia-sip opus libogg libcurl glib pkg-config gengetopt autoconf automake libtool

For what concerns libsrtp, which needs to be installed manually, just pass /usr/local as a prefix when configuring, and proceed as normal:

[..]
./configure --prefix=/usr/local
[..]

Finally, you may need to provide a custom prefix and PKG_CONFIG_PATH when configuring Janus as well:

./configure --prefix=/usr/local/janus PKG_CONFIG_PATH=/usr/local/opt/openssl/lib/pkgconfig

Everything else works exactly the same way as on Linux.

Configure and start

To start the gateway, you can use the janus executable. There are several things you can configure, either in a configuration file:

<installdir>/etc/janus/janus.cfg

or on the command line:

<installdir>/bin/janus --help

janus 0.2.5

Usage: janus [OPTIONS]...

-h, --help                    Print help and exit
-V, --version                 Print version and exit
-b, --daemon                  Launch Janus in background as a daemon
                              (default=off)
-N, --disable-stdout          Disable stdout based logging  (default=off)
-L, --log-file=path           Log to the specified file (default=stdout only)
-i, --interface=ipaddress     Interface to use (will be the public IP)
-P, --plugins-folder=path     Plugins folder (default=./plugins)
-C, --config=filename         Configuration file to use
-F, --configs-folder=path     Configuration files folder (default=./conf)
-c, --cert-pem=filename       DTLS certificate
-k, --cert-key=filename       DTLS certificate key
-S, --stun-server=filename    STUN server(:port) to use, if needed (e.g.,
							  gateway behind NAT, default=none)
-1, --nat-1-1=ip              Public IP to put in all host candidates,
                              assuming a 1:1 NAT is in place (e.g., Amazon
                              EC2 instances, default=none)
-E, --ice-enforce-list=list   Comma-separated list of the only interfaces to
                              use for ICE gathering; partial strings are
                              supported (e.g., eth0 or eno1,wlan0,
                              default=none)
-X, --ice-ignore-list=list    Comma-separated list of interfaces or IP
                              addresses to ignore for ICE gathering;
                              partial strings are supported (e.g.,
                              vmnet8,192.168.0.1,10.0.0.1 or
                              vmnet,192.168., default=vmnet)
-6, --ipv6-candidates         Whether to enable IPv6 candidates or not
                              (experimental)  (default=off)
-l, --libnice-debug           Whether to enable libnice debugging or not
                              (default=off)
-I, --ice-lite                Whether to enable the ICE Lite mode or not
                              (default=off)
-T, --ice-tcp                 Whether to enable ICE-TCP or not (warning: only
                              works with ICE Lite)
                              (default=off)
-U, --bundle                  Whether to force BUNDLE or not (whether audio,
                              video and data will always be bundled)
                              (default=off)
-u, --rtcp-mux                Whether to force rtcp-mux or not (whether RTP
                              and RTCP will always be muxed)  (default=off)
-q, --max-nack-queue=number   Maximum size of the NACK queue (in ms) per user
                              for retransmissions
-t, --no-media-timer=number   Time (in s) that should pass with no media
                              (audio or video) being received before Janus
                              notifies you about this
-r, --rtp-port-range=min-max  Port range to use for RTP/RTCP (only available
							  if the installed libnice supports it)
-d, --debug-level=1-7         Debug/logging level (0=disable debugging,
                              7=maximum debug level; default=4)
-D, --debug-timestamps        Enable debug/logging timestamps  (default=off)
-o, --disable-colors          Disable color in the logging  (default=off)
-a, --apisecret=randomstring  API secret all requests need to pass in order
                              to be accepted by Janus (useful when wrapping
                              Janus API requests in a server, none by
                              default)
-A, --token-auth              Enable token-based authentication for all
                              requests  (default=off)
-e, --event-handlers          Enable event handlers  (default=off)

Options passed through the command line have the precedence on those specified in the configuration file. To start the gateway, simply run:

<installdir>/bin/janus

This will start the gateway, and have it look at the configuration file.

As far as transports are concerned (that is, with respect to how you can interact with your Janus instance), using the default configuration files provided after issuing a make configs will result in Janus only enabling an HTTP webserver (port 8088) and a plain WebSocket server (8188), assuming the related transport modules have been compiled, of course. To enable HTTPS or Secure WebSockets support, edit the related transport configuration file accordingly. You can also change the base path that the webserver uses: by default this is /janus, but you can change it to anything you want and with any nesting you want (e.g., /mypath, /my/path, or /my/really/nested/path). This is done to allow you to more easily customize rules in any frontend you may have (e.g., Apache in front of your services). Please notice that the path configuration is not provided for WebSockets, instead, as it is not needed there. The RabbitMQ module, if compiled, is disabled by default, so you'll have to enable it manually if interested in it.

To test whether it's working correctly, you can use the demos provided with this package in the html folder: these are exactly the same demos available online on the project website. Just copy the file it contains in a webserver, or use a userspace webserver to serve the files in the html folder (e.g., with php or python), and open the index.html page in either Chrome or Firefox. A list of demo pages exploiting the different plugins will be available. Remember to edit the transport/port details in the demo JavaScript files if you changed any transport-related configuration from its defaults.

Help us!

Any thought, feedback or (hopefully not!) insult is welcome!

Developed by @meetecho