@browsercore/http3

HTTP/3 framing + QPACK over QUIC streams.

Responsibility

HTTP/3 frame parsing/serialization over typed QUIC streams, QPACK header compression over unidirectional encoder/decoder streams, the control-stream SETTINGS exchange, GOAWAY graceful shutdown, and PUSH_PROMISE / CANCEL_PUSH / MAX_PUSH_ID handling. The package knows nothing about the underlying QUIC transport — it could be a real QUIC connection, a pipe, or a test double.

What it does NOT know about

• UDP / QUIC / TLS 1.3 (handled by the QUIC connection abstraction)
• TCP, DNS, or sockets
• HTTP/1.1 or HTTP/2
• Browser fingerprints

Public API

import { connectHttp3, GoawayReceivedError } from "@browsercore/http3";

const conn = await connectHttp3({ quic: quicConnection });

const res = await conn.request({
    method: "GET",
    scheme: "https",
    authority: "example.com",
    path: "/index.html",
    headers: new Map([["accept", "text/html"]]),
    body: undefined,
});

console.log(res.statusCode, res.body);
await conn.goaway(0n);
await conn.close();

Types

| Export | Kind | Purpose | | --- | --- | --- | | Http3Connection | interface | Public contract higher layers depend on | | connectHttp3() | function | Wrap a QUIC connection with HTTP/3 | | Http3Frame | discriminated union | Every HTTP/3 frame variant | | Http3FrameType | const object | RFC 9114 frame type ids | | Http3StreamType | const object | QUIC unidirectional-stream type ids | | Http3Settings | const object | RFC 9114 SETTINGS identifiers | | QuicConnection | interface | Injected QUIC abstraction | | Http3Error | class | Base typed error | | GoawayReceivedError | class | Peer sent GOAWAY | | PushCancelledError | class | Peer cancelled a push | | FrameParseError | class | Malformed frame | | QpackDecodeError | class | Malformed QPACK block | | SettingsAckTimeoutError | class | SETTINGS ACK timed out | | SettingsViolationError | class | Peer violated our SETTINGS |

Dependency graph

@browsercore/http3
  └─ (no @browsercore/* dependencies — QUIC connection is injected)

The QUIC connection is injected — @browsercore/http3 imports only the QuicConnection type, never a concrete implementation. The concrete QUIC implementation lives in a separate @browsercore/quic package (future) and satisfies this interface. HTTP/3 needs no crypto of its own (QPACK is compression-only, and there is no PING frame), so the package has no runtime dependency on any other @browsercore/* package.

No other @browsercore/* packages are imported.

Position in BrowserCore

Application
      │
   @browsercore/http3
      │
   @browsercore/quic
      │
     UDP
      │
      IP

Every higher networking layer communicates with the network exclusively through the layers below it.