HTTP/2

Enable HTTP/2

HTTP/1.1 is enabled by default. Use a persistent Client to enable HTTP/2:

import req

def main() raises:
    var owner = req.Client(http2=True)
    with owner.context() as client:
        var response = client.get("https://example.com")
        response.raise_for_status()
        print(response.http_version)

With http1=True, http2=True, HTTPS negotiates HTTP/2 through ALPN and can fall back to HTTP/1.1. Set http1=False, http2=True for HTTP/2-only mode. Disabling both protocols raises InvalidRequest. Module-level helpers use HTTP/1.1; use Client or HTTPTransport for protocol selection.

The native libcurl must have HTTP/2 support. HTTP/2-only mode additionally requires libcurl 8.10 or later. Unsupported configurations fail with InvalidRequest when constructing the client. Req supports connection reuse and overlapping HTTP/2 response streams; the Client remains single-threaded.

Use Limits to manage physical connections and Timeout.pool to bound waits for stream capacity.