WebRTC Ruby

WebRTC bindings for Ruby, providing real-time audio, video, and data channel capabilities.

This project provides a practical, webrtc-rs-compatible API surface in Ruby, with a mix of:

• native-backed features through libdatachannel C API
• Ruby compatibility/typing layers for API parity

• WebRTC.init / WebRTC.cleanup
• RTCPeerConnection
  • offer/answer
  • local/remote description
  • ICE candidate add
  • connection/ICE/signaling/gathering states + callbacks
  • data channel callbacks
  • track callbacks
  • add/remove track path (via native track ID)
• RTCDataChannel
  • create/close/send
  • open/message/close callbacks
  • buffered amount
• RTCSessionDescription
• RTCIceCandidate

• Factory API
  • CurrentTaskQueueFactory
  • PeerConnectionFactory
  • WebRTC.create_modular_peer_connection_factory
• Observer API
  • CreateSessionDescriptionObserver
  • SetLocalDescriptionObserver
  • SetRemoteDescriptionObserver
  • AddIceCandidateObserver
  • DataChannelObserver
  • RTCStatsCollectorCallback
• Typed parity classes
  • CreateOfferOptions, CreateAnswerOptions
  • DataChannelInit, DataChannelMessage
  • RTP parameter/capability classes
  • RTCError and enum modules
  • media interface classes
  • VideoFrame, I420Buffer

• RTCStatsCollectorCallback and RTCStatsResponse are wired.
• DataChannel message/byte counters are measured from actual send/receive events.
• Low-level RTP/ICE transport metrics remain limited by libdatachannel C API exposure.

• Ruby 3.1+
• CMake
• OpenSSL development libraries

Add this line to your application's Gemfile:

gem 'webrtc-ruby'

Then run:

bundle install

The gem requires a native extension (ext/webrtc_ruby) and libdatachannel.

brew install cmake openssl

# Clone and build libdatachannel
git clone --depth 1 --recurse-submodules https://github.com/paullouisageneau/libdatachannel.git vendor/libdatachannel
cd vendor/libdatachannel
mkdir build && cd build
cmake -DUSE_GNUTLS=0 -DUSE_NICE=0 -DNO_WEBSOCKET=1 -DNO_EXAMPLES=1 -DNO_TESTS=1 ..
make -j$(sysctl -n hw.ncpu)
cd ../../..

# Build extension
cd ext/webrtc_ruby
mkdir -p build && cd build
cmake ..
make

sudo apt install build-essential cmake git libssl-dev pkg-config

# Clone and build libdatachannel
git clone --depth 1 --recurse-submodules https://github.com/paullouisageneau/libdatachannel.git vendor/libdatachannel
cd vendor/libdatachannel
mkdir build && cd build
cmake -DUSE_GNUTLS=0 -DUSE_NICE=0 -DNO_WEBSOCKET=1 -DNO_EXAMPLES=1 -DNO_TESTS=1 ..
make -j$(nproc)
cd ../../..

# Build extension
cd ext/webrtc_ruby
mkdir -p build && cd build
cmake ..
make

require 'webrtc'

WebRTC.init

pc1 = WebRTC::RTCPeerConnection.new
pc2 = WebRTC::RTCPeerConnection.new

pc1_candidates = []
pc2_candidates = []

pc1.on_ice_candidate { |c| pc1_candidates << c if c }
pc2.on_ice_candidate { |c| pc2_candidates << c if c }

pc2.on_data_channel do |dc|
  dc.on_message { |msg| puts "pc2 recv: #{msg.data}" }
end

dc1 = pc1.create_data_channel('chat')
dc1.on_open { puts 'pc1 data channel open' }
dc1.on_message { |msg| puts "pc1 recv: #{msg.data}" }

offer = pc1.create_offer.await
pc1.set_local_description(offer).await
pc2.set_remote_description(offer).await

answer = pc2.create_answer.await
pc2.set_local_description(answer).await
pc1.set_remote_description(answer).await

pc1_candidates.each { |c| pc2.add_ice_candidate(c).await rescue nil }
pc2_candidates.each { |c| pc1.add_ice_candidate(c).await rescue nil }

pc1.close
pc2.close
WebRTC.cleanup

factory = WebRTC.create_modular_peer_connection_factory
pc = factory.create_peer_connection(
  ice_servers: [{ urls: 'stun:stun.l.google.com:19302' }]
)

observer = WebRTC::CreateSessionDescriptionObserver.new(
  on_success: ->(desc) { puts "created: #{desc.type}" },
  on_failure: ->(err) { warn err.message }
)

pc.create_offer(observer: observer).await

report = pc.get_stats.await

report.each do |_id, stat|
  case stat
  when WebRTC::RTCDataChannelStats
    puts "dc bytes sent=#{stat.bytes_sent} recv=#{stat.bytes_received}"
  when WebRTC::RTCTransportStats
    puts "transport bytes sent=#{stat.bytes_sent} recv=#{stat.bytes_received}"
  end
end

After checking out the repo, install dependencies:

bundle install

• Building the native extension and running tests require libdatachannel.
• You must use one of these approaches before testing:

# Option A (recommended): keep a local vendor copy
git clone --depth 1 --recurse-submodules https://github.com/paullouisageneau/libdatachannel.git vendor/libdatachannel
cd vendor/libdatachannel
mkdir -p build && cd build
cmake .. -DCMAKE_BUILD_TYPE=Release -DNO_EXAMPLES=ON -DNO_TESTS=ON
cmake --build .
cd ../../..

# Option B: install libdatachannel system-wide (pkg-config discoverable)
# In this case CMake falls back to pkg-config when vendor/libdatachannel is absent.

# Build native extension first
cd ext/webrtc_ruby
mkdir -p build && cd build
cmake ..
cmake --build .
cd ../../..

# Run test suite (macOS)
DYLD_LIBRARY_PATH="ext/webrtc_ruby/build:vendor/libdatachannel/build" bundle exec rspec

# Run test suite (Linux)
LD_LIBRARY_PATH="ext/webrtc_ruby/build:vendor/libdatachannel/build" bundle exec rspec

This project is available under the Apache License 2.0.

Bug reports and pull requests are welcome at:

• https://github.com/ydah/webrtc-ruby