initial-setup of py-webrtc #557

Nkovaturient · 2025-04-03T20:46:43Z

What was wrong?

This is an initial prototype of webrtc-feat for further guidance on py-webrtc-support implementation.

Issue #546

Implementations & Enhancements

WebRTC Transport Setup

Established WebRTC Peer Connection (RTCPeerConnection) for direct communication.
Implemented SDP exchange via a WebSocket-based signaling server (listen_signaling).
Integrated WebRTC Data Channels (RTCDataChannel) for efficient peer-to-peer messaging.
Included robust error handling and logging improvements.

Signaling Protocol & SDP Exchange

WebSockets are used for signaling to register and communicate SDP offers/answers.
Ensures smooth connection establishment between peers via offer-answer negotiation.
Added connection initiation for peer discovery (initiate_connection).

Decentralized Peer Discovery (GossipSub & libp2p)

Integrated GossipSub to enable decentralized peer advertisement & discovery.
Implemented real-time peer discovery via Pubsub, where peers broadcast and subscribe to "webrtc-peer-discovery".
Enhanced peer connectivity through multiaddr parsing for WebRTC protocols

Questions

1.) Should we rely entirely on WebSockets for signaling, or use DHT as a fallback?

2)Multiaddr Handling & Validation

Does our current parse_webrtc_multiaddr() function correctly align with libp2p's expected formats?
Should we add additional multi-protocol support (/webrtc-direct, /wss, etc.)?

3.)Peer Discovery Optimization

Are we handling peer discovery in the most efficient manner using GossipSub?

To-Do

Implement STUN/TURN for NAT traversal.
Integrate AutoNAT for seamless peer connectivity.
Optimize connection stability for WebRTC behind firewalls.
Connection Management - Ensure robust connection handling in restricted network environments
Address network congestion and packet loss optimizations

Helpful resources

js-libp2p-webrtc
go-libp2p-webrtc

pacrob · 2025-04-04T17:44:42Z

Just a note, py-libp2p is using trio for async functionality over asyncio.

Nkovaturient · 2025-04-04T20:00:42Z

@pacrob noted, will modify, thanks!

… add-webrtc-in-pylibp2p

Nkovaturient · 2025-04-13T17:43:05Z

New Commit entails the following changes:-

🔧 `webrtc.py` – Core WebRTC Transport Layer for libp2p

We implemented a custom WebRTC transport for libp2p nodes using aiortc, designed to enable peer-to-peer communication over WebRTC data channels.

✅ Key Components:

WebRTCRawConnection:
- Wraps RTCDataChannel to provide a trio-based raw I/O interface.
- Supports async read, write, and close.
WebRTCListener:
- Listens for incoming WebRTC connection offers.
- Accepts incoming data channels via a signaling protocol (/libp2p/webrtc/signal/1.0.0).
- Handles the full SDP offer-answer exchange and prepares the raw connection.
WebRTCTransport:
- Implements ITransport interface.
- Handles peer connection setup:
  - Creating and opening data channels.
  - Exchanging SDP offers/answers.
  - Handling ICE candidates (optionally).
- Adds support for GossipSub-based peer discovery over topic webrtc-peer-discovery.
- Implements both dial() and create_listener() for WebRTC signaling.
parse_webrtc_multiaddr:
- Validates and parses multiaddrs that include the /webrtc protocol.

🧪 `test_loopback.py` – Functional Loopback Testing

We created a loopback test using two libp2p BasicHosts to simulate a full peer-to-peer WebRTC connection over the new transport.

✅ Highlights:

build_host(name):
- Builds a libp2p host with:
  - TCP base transport.
  - Noise encryption.
  - Mplex stream multiplexer.
  - Registers a /ws WebSocket listen address
run_loopback_test():
- Host B:
  - Initializes WebRTC transport.
  - Creates a listener and accepts incoming connections.
  - Reads a message and replies.
- Host A:
  - Initializes another WebRTC transport.
  - Connects to Host B using dial().
  - Sends a message and reads the response.
Trio Nursery:
- Orchestrates both client and server asynchronously in the same process.

Questions:

the correct multiaddr for webrtc connections is: /ip4/127.0.0.1/tcp/9095/ws/p2p/{peer_id_b}/p2p-circuit/webrtc ?
Is the webrtc.py setup connections, listener and dialing up to mark as per libp2p transport interface?
our loopback-test is printing the two peerID of two hosts, further improving it to establish connections and exchange messages

… add-webrtc-in-pylibp2p

Nkovaturient · 2025-04-18T20:31:34Z

Commit: refactor-webrtc-setup-and-loopback-test

Description

- Key improvements to the` webrtc.py` file in the `libp2p.transport.webrtc` module:

Removed redundancies and unused imports
Ensured clean and consistent channel signaling and ICE candidate exchange
Added structured handling for stream-based SDP/ICE communication

✅ ICE Trickling: Implemented and now symmetric (caller/callee)
✅ Mplex: Fully integrated inside WebRTCRawConnection
✅ DataChannel: Integrated properly on both ends
✅ dial() and listen() lifecycle flows are connected

Updates:

WebRTCListener | Fully utilized for accepting connections from peers via set_stream_handler
WebRTCTransport | Used to establish offer/answer over the signaling stream
DataChannel Check | Ensures the channel is created before attempting communication
Connection Abstraction | Uses WebRTCRawConnection to simulate message exchange via write() and read()

Troubleshooting ahead:

Fix test_loopback WebRTC transport errors and mypy typing mismatches
mypy: Incompatible override of create_listener in webRTCTransport() of ITransport attribute
Updating loopback test with correct handler and address formats
Add valid multiaddrs to peerstore before dial attempts.

Test_loopback.py Result:

Lint Run Result: All lint issues fixed except `rst-file` and `mypy typing mismatches`

seetadev · 2025-04-29T09:35:36Z

@Nkovaturient : Great progress. Please try and arrive at a good conclusion on the issues by Thursday.

Nkovaturient · 2025-04-30T09:14:25Z

@Nkovaturient : Great progress. Please try and arrive at a good conclusion on the issues by Thursday.

@seetadev yeah, updating you shortly.

… add-webrtc-in-pylibp2p

Nkovaturient · 2025-05-13T14:07:32Z

@seetadev
Delighted to update you that:

webrtc transport, listener and connection are successfully implemented along with robust signalling service and generating certhash functionality for P2P connections via webrtc-direct
— testing phase is underway (92%✅)✨🚀

seetadev · 2025-05-13T17:31:28Z

@seetadev Delighted to update you that:

webrtc transport, listener and connection are successfully implemented along with robust signalling service and generating certhash functionality for P2P connections via webrtc-direct
— testing phase is underway (92%✅)✨🚀

@Nkovaturient : Thank you so much for sharing the updates and code commits. Appreciate your contribution.

Wish if you could debug some of the build issues that are not passing after running the latest CI/CD checks.

Wish to also share that I discussed with rust-libp2p team on webrtc and documented a test plan for webrtc fallback relay testing matrix : #601

Please keep in touch with @Winter-Soren as he implements circuit relay and hole punching (support needed for webrtc in production).

Nkovaturient · 2025-05-13T18:14:15Z

@seetadev Sure, actively working on the build issues + test suite
Also, I will coordinate with him regarding the webrtc fallback relay.
Thank you for informing.💯✨

… add-webrtc-in-pylibp2p

seetadev · 2025-05-30T20:12:24Z

@seetadev Sure, actively working on the build issues + test suite Also, I will coordinate with him regarding the webrtc fallback relay. Thank you for informing.💯✨

@Nkovaturient : We are almost through with the circuit relay PR. @Winter-Soren and I will be moving over to hole punching initiative in the coming week. Will keep you posted.

This will help you have the requisite NAT Traversal stack required in WebRTC. Autonat is complete and productionized. @Winter-Soren has ensured NAT Traversal features are production ready.

Please try AutoNAT functionality, which is fully ready: please visit autonat implementation video and testcases video
url at https://drive.google.com/drive/folders/1SxRBi5p23e45JiBMt5Lol7JUfADc0mdT?usp=sharing

Nkovaturient · 2025-05-31T20:21:45Z

@seetadev humbly appreciate ur updates! Im taking care of it.

… add-webrtc-in-pylibp2p

sukhman-sukh · 2025-07-16T10:54:12Z

libp2p/transport/webrtc/gen_certhash.py

+    return actual_hash == expected_hash
+
+
+def create_webrtc_direct_multiaddr(ip: str, port: int, peer_id: ID) -> Multiaddr:


Why are here 2 functions for direct_multiaddr.

sukhman-sukh · 2025-07-16T11:07:31Z

libp2p/transport/webrtc/gen_certhash.py

+    if not isinstance(peer_id, ID):
+        peer_id = ID(peer_id)
+
+    base = f"/ip4/{ip}/udp/9000/webrtc-direct/certhash/{certhash}/p2p/{peer_id}"


can we get port also as optional argument with default value 9000 instead of hardcoding

seetadev · 2025-07-19T10:55:16Z

@Nkovaturient : Hi Neha. Hope you're doing well.

Thanks again for your efforts. Wish to also thank @sukhman-sukh for his feedback and review to the PR.

To help accelerate finalization and testing, could you please add @sukhman-sukh as a collaborator to your current WebRTC PR? He’s been closely following the architecture and has already worked on related components, so his input and hands-on support should help us move things forward more quickly.

Thanks again for your continued efforts — this is an exciting milestone for the project, and we’re looking forward to seeing it land soon.

Nkovaturient · 2025-07-20T12:04:45Z

Hello there @seetadev
Adhering to this PR and due to various py dependencies issues and module imports err on windows after py-libp2p version updates, there was untypical, irrelevant issues arising on this branch while workin, hence created afresh branch (PR #780 ) and implemented the complete setup as efficiently as I could, with updates and dependencies checks.

Looking forward to collaborate wid @sukhman-sukh on further improvements and robust setup.

Thank you!

seetadev · 2025-07-20T13:28:27Z

@Nkovaturient : Thanks for the update. Sure, please include the feedback points by @sukhman-sukh in the latest PR.

Wish to share that @sukhman-sukh is working on developing a NAT integrated transport layer production stack for webrtc (private to private) and integrating dcutr (hole punching), circuit relay and autonat in this issue: please visit #773 .

You can also ask him to include the NAT traversal integration, and contribute, integrate NAT traversal workflows in webrtc-direct efforts shared in the new PR at #780 . He did review this current PR (#557) before beginning the webrtc efforts and arrived at a set of key milestones he needed to achieve (in sync with the latest NAT traversal developments).

initial-setup

3ee28ab

Nkovaturient added 2 commits April 13, 2025 22:32

improve-webrtc-and-integrate-loopback_test

1ea3a04

Merge branch 'main' of https://github.com/Nkovaturient/py-libp2p into…

b7e933d

… add-webrtc-in-pylibp2p

Nkovaturient mentioned this pull request Apr 13, 2025

Add Support for WebRTC set-up in py-libp2p #546

Open

Nkovaturient added 3 commits April 14, 2025 01:37

lint-fixes

e73b519

Merge branch 'main' of https://github.com/Nkovaturient/py-libp2p into…

440a963

… add-webrtc-in-pylibp2p

refactor-webrtc-setup-and-loopback-test

95e0ec9

Nkovaturient added 2 commits May 12, 2025 12:31

Merge branch 'main' of https://github.com/Nkovaturient/py-libp2p into…

92d74b9

… add-webrtc-in-pylibp2p

feat(webrtc): revamp transport and signalling service

690c1f9

Nkovaturient added 2 commits May 18, 2025 18:21

Merge branch 'main' of https://github.com/Nkovaturient/py-libp2p into…

2cb5b81

… add-webrtc-in-pylibp2p

Merge branch 'main' of https://github.com/Nkovaturient/py-libp2p into…

2ffec86

… add-webrtc-in-pylibp2p

Nkovaturient added 5 commits June 3, 2025 02:28

feat(webrtc): add maddr parsing, SDP munging& test coverage

dfe6629

Merge branch 'main' of https://github.com/Nkovaturient/py-libp2p into…

ca6c3a1

… add-webrtc-in-pylibp2p

fix(ci): resolve WebRTC-listener test suite& build issues

b957b46

fix(docs):dependency config for builds

5ac3a60

fix(docs):rst config for builds

444fd97

sukhman-sukh reviewed Jul 16, 2025

View reviewed changes

Nkovaturient mentioned this pull request Jul 20, 2025

Feat/add webrtc transport #780

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seetadev closed this Jul 20, 2025

		return actual_hash == expected_hash


		def create_webrtc_direct_multiaddr(ip: str, port: int, peer_id: ID) -> Multiaddr:

initial-setup of py-webrtc #557

initial-setup of py-webrtc #557

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Conversation

Nkovaturient commented Apr 3, 2025

What was wrong?

Implementations & Enhancements

Questions

To-Do

Helpful resources

Uh oh!

pacrob commented Apr 4, 2025

Uh oh!

Nkovaturient commented Apr 4, 2025

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Nkovaturient commented Apr 13, 2025

New Commit entails the following changes:-

🔧 webrtc.py – Core WebRTC Transport Layer for libp2p

✅ Key Components:

🧪 test_loopback.py – Functional Loopback Testing

✅ Highlights:

Questions:

Uh oh!

Nkovaturient commented Apr 18, 2025

Commit: refactor-webrtc-setup-and-loopback-test

Description

Updates:

Troubleshooting ahead:

Test_loopback.py Result:

Lint Run Result: All lint issues fixed except rst-file and mypy typing mismatches

Uh oh!

seetadev commented Apr 29, 2025

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Nkovaturient commented Apr 30, 2025

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Nkovaturient commented May 13, 2025

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seetadev commented May 13, 2025

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Nkovaturient commented May 13, 2025

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seetadev commented May 30, 2025

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Nkovaturient commented May 31, 2025

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sukhman-sukh Jul 16, 2025

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sukhman-sukh Jul 16, 2025

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seetadev commented Jul 19, 2025

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Nkovaturient commented Jul 20, 2025

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seetadev commented Jul 20, 2025

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🔧 `webrtc.py` – Core WebRTC Transport Layer for libp2p

🧪 `test_loopback.py` – Functional Loopback Testing

Lint Run Result: All lint issues fixed except `rst-file` and `mypy typing mismatches`