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HTTP protocol compliance

Ensure code adheres to HTTP protocol standards and handles different protocol versions correctly. This includes respecting protocol limitations, using appropriate status codes, and implementing proper fallbacks.

raw .md Networking TypeScript

Key considerations:

HTTP/2 doesn’t support status messages, so avoid setting statusMessage for HTTP/2 connections
Use reliable endpoints for server health checks that return success status codes rather than application logic that might fail
Handle redirect status codes appropriately with proper fallback mechanisms

Example implementation:

// Good: Check protocol version before setting status message
export async function toNodeRequest(res: Response, nodeRes: ServerResponse) {
  nodeRes.statusCode = res.status;
  // HTTP/2 doesn't support status messages
  // https://datatracker.ietf.org/doc/html/rfc7540#section-8.1.2.4
  if (nodeRes.httpVersion !== '2.0') {
    nodeRes.statusMessage = res.statusText;
  }
}

// Good: Use reliable endpoint for health checks
await waitOn({
  resources: [
    `http://${args.host ?? "localhost"}:${args.port}${args.basename ?? "/favicon.ico"}`,
  ]
});

// Good: Handle redirect status codes with appropriate fallbacks
if (redirectStatusCodes.has(response.status)) {
  let location = response.headers.get("Location");
  let delay = response.status === 302 ? 2 : 0;
  // Implement meta refresh fallback
}

This ensures network communication follows established protocols and handles edge cases gracefully across different HTTP versions and scenarios.