An example WebTransport-over-HTTP/3 server in Go, and browser client in JavaScript, using github.com/adriancable/webtransport-go.
The server app demonstrates how to create a WebTransport server, accept an incoming session, accept client-initiated and create server-initiated bidirectional and unidirectional streams, and send and receive data.
The browser client app demonstrates how to create a WebTransport connection to the server, create some streams, send data back and forth, and then close the transport.
You'll need to get a certificate for your server. Please read the comments at the top of Google's WebTransport server example in Python for detailed instructions. Then, put your cert.pem and cert.key files in the same directory that you've checked this example out in.
go run main.go
You should see:
Launching WebTransport server at :4433
Easiest: launch Chrome, then File / Open File and select client.html.
More representative: spin up an HTTP server on port 8000, then point Chrome at http://localhost:8000/client.html. If you change the host or the port
you're serving from, you'll need to adjust AllowedOrigins in main.go accordingly.
Accepted incoming WebTransport session
Listening on server-initiated bidi stream 1
Sending to server-initiated bidi stream 1: bidi
Sending to server-initiated uni stream 1: uni
Accepting incoming bidi stream: 4
Accepting incoming uni stream: 6
Accepting incoming uni stream: 10
Accepting incoming uni stream: 14
Received datagram: Datagram
Sending datagram: DATAGRAM
Received from server-initiated bidi stream 1: BIDI
Received from uni stream: Uni stream
Received from bidi stream 4: Bidi stream
Sending to bidi stream 4: BIDI STREAM
Received datagram: Datagram again
Sending datagram: DATAGRAM AGAIN
Received from bidi stream 4: Bidi stream again
Received from uni stream: Uni stream again
Sending to bidi stream 4: BIDI STREAM AGAIN
2022/02/23 18:03:28 Error reading from bidi stream 4: EOF
Session closed, ending datagram listener: WebTransport stream closed
Session closed, not accepting more bidi streams: context canceled
Session closed, not accepting more uni streams: context canceled
2022/02/23 18:03:30 Error reading from uni stream 14: stream 14 canceled with error code 271
2022/02/23 18:03:30 Error reading from server-initiated bidi stream 1: stream 1 canceled with error code 271
Received an incoming bidi stream
client.html:61 Received an incoming uni stream
client.html:56 Received on incoming bidi stream: bidi
client.html:63 Received on incoming uni stream: uni
client.html:46 Received datagram: DATAGRAM
client.html:49 Received on bidi stream: BIDI STREAM
client.html:46 Received datagram: DATAGRAM AGAIN
client.html:49 Received on bidi stream: BIDI STREAM AGAIN
client.html:17 Datagram receive error: WebTransportError: The session is closed.
at main (client.html:82:21)
client.html:17 Incoming bidi stream receive error: WebTransportError: The session is closed.
at main (client.html:82:21)
client.html:17 Incoming uni stream receive error: WebTransportError: The session is closed.
at main (client.html:82:21)
client.html:30 Connection closed normally
Provided under the MIT license.