http.sf

import saffire;
import http::request;
import saffire::sapi;

class http {
  protected property sapi = null;

  public method detectSapi() {
    switch (saffire.sapi()) {
      case "fastcgi" :
        return saffire.sapi.fastcgi();
      case "cli" :
        return saffire.sapi.dummy();
      default :
        throw new Exception("Cannot find interface for this sapi");
    }
  }

  public method setSapi(Sapi sapi) {
    self.sapi = sapi;
  }

  public method getSapi() {
    if (! self.sapi) self.sapi = self.detectSapi();
    return self.sapi;
  }

  // Returns a fileld request
  public method getMainRequest() {
    req = self.getRequest();
    sapi = self.getSapi();
    sapi.fillRequest(req);
    return req;
  }

  // Just returns an empty request
  public method getRequest() {
    return new request();
  }
}

request.sf

import net::uri;  // as example, we use different modules for IP and URI parsing (getQueryString getHostname etc)
import net::ip;  // GetHostByName, getHostByAddress, isvalidIp() etc

class Request {
  protected property client_ip;
  protected property method;

  public method getMethod() {
    return self.method;
  }

  public method setMethod(method) {
    self.method = method.uppercase;
  }

  public method setClientIp(ip) {
    if (ip.isValidIp(ip)) self.client_ip = ip;
  }
 
  ....
}

sapi::fastcgi.sf

import ::http::request;
import ::_sfl::fastcgi as fcgi;  // Internal fastcgi module

class fastcgi implements sapi {
  public method fillRequest(Request req) {
    req.client_ip = self.getParameter("CLIENT_IP", "");
    req.method = self.getParameter("METHOD", "");
  }

  public method getParameter(key, default) {
    // fcgi.env is a hash object
    return fcgi.env[key] ?? default; // coalesce. Sweet!
  }

  public method hasParameter(key) {
    return fcgi.env.has(key);
  }

}