Proxy Virtual Hosts
Virtual host routing maps the HTTP Host header (or TLS SNI for HTTPS) to different upstreams. This is how nyx-proxy serves 4 domains on port :443 simultaneously.
Code
// nyx-proxy virtual host routing — match Host header to upstream
// Routing nyx-proxy — mapear Host header a upstream
fn route_for_host(host: String) -> String {
// Map each domain to an upstream IP:port
if host == "nyxlang.com" { return "127.0.0.1:3001" }
if host == "nyxkv.com" { return "127.0.0.1:3002" }
if host == "serve.nyxlang.com" { return "127.0.0.1:3003" }
if host == "proxy.nyxlang.com" { return "127.0.0.1:3005" }
// Default upstream
return "127.0.0.1:3001"
}
fn parse_host_header(request: String) -> String {
// Find "Host: " in the request headers
let idx: int = request.indexOf("Host: ")
if idx < 0 { return "" }
let start: int = idx + 6
let end: int = request.indexOf("\r\n", start)
if end < 0 { return "" }
return request.substring(start, end)
}
fn main() -> int {
// Simulate reading an HTTP request
let request: String = "GET / HTTP/1.1\r\nHost: nyxkv.com\r\nUser-Agent: test\r\n\r\n"
let host: String = parse_host_header(request)
let upstream: String = route_for_host(host)
print("incoming Host: " + host)
print("route to -> " + upstream)
// In production, nyx-proxy tls_accept() reads SNI, matches the cert,
// then Host header matches the vhost config, forwards the request
// via tcp_connect to the upstream, and pipes bytes bidirectionally.
return 0
}Output
incoming Host: nyxkv.com route to -> 127.0.0.1:3002
Explanation
Virtual hosting is how one server IP hosts many websites. For plain HTTP, the Host header inside the request tells you which site the client wants; for HTTPS, the SNI extension in the TLS ClientHello does the same thing before any HTTP flows. nyx-proxy uses both in layers: SNI to pick the right certificate at TLS handshake, then Host header to pick the right upstream at L7. route_for_host here is a flat lookup, but the real config loads this table from proxy.toml so operations can add domains without recompiling. This exact pattern serves the four nyxlang.com-family domains from a single port :443.