platform: modularize api/gui, add docs-tests-web foundation, and refresh root config

selective-vpn-api/app/egress_identity_geo.go

@@ -0,0 +1,76 @@
+package app
+
+import (
+	"fmt"
+	egressutilpkg "selective-vpn-api/app/egressutil"
+	"strings"
+	"time"
+)
+
+func (s *egressIdentityService) lookupGeo(ip string, force bool) (string, string, error) {
+	ip = strings.TrimSpace(ip)
+	if ip == "" {
+		return "", "", fmt.Errorf("empty ip")
+	}
+	now := time.Now()
+
+	s.geoMu.Lock()
+	if entry, ok := s.geoCache[ip]; ok && !entry.ExpiresAt.IsZero() && now.Before(entry.ExpiresAt) {
+		code := egressutilpkg.NormalizeCountryCode(entry.CountryCode)
+		name := strings.TrimSpace(entry.CountryName)
+		errMsg := strings.TrimSpace(entry.LastError)
+		s.geoMu.Unlock()
+		if code != "" || name != "" {
+			return code, name, nil
+		}
+		if errMsg != "" && !force {
+			return "", "", fmt.Errorf("%s", errMsg)
+		}
+		if !force {
+			return "", "", nil
+		}
+		// Force refresh bypasses negative geo cache to recover country flag quickly.
+	}
+	stale := s.geoCache[ip]
+	s.geoMu.Unlock()
+
+	geoURLs := egressGeoEndpointsForIP(ip)
+	errs := make([]string, 0, len(geoURLs))
+	for _, rawURL := range geoURLs {
+		body, err := egressutilpkg.HTTPGetBody(egressHTTPClient, rawURL, egressIdentityGeoTimeout, "selective-vpn-api/egress-identity", 8*1024)
+		if err != nil {
+			errs = append(errs, err.Error())
+			continue
+		}
+		code, name, err := egressutilpkg.ParseGeoResponse(body)
+		if err != nil {
+			errs = append(errs, err.Error())
+			continue
+		}
+
+		s.geoMu.Lock()
+		s.geoCache[ip] = egressGeoCacheEntry{
+			CountryCode: egressutilpkg.NormalizeCountryCode(code),
+			CountryName: strings.TrimSpace(name),
+			ExpiresAt:   now.Add(egressIdentityGeoCacheTTL),
+		}
+		s.geoMu.Unlock()
+		return egressutilpkg.NormalizeCountryCode(code), strings.TrimSpace(name), nil
+	}
+
+	if strings.TrimSpace(stale.CountryCode) != "" || strings.TrimSpace(stale.CountryName) != "" {
+		return egressutilpkg.NormalizeCountryCode(stale.CountryCode), strings.TrimSpace(stale.CountryName), nil
+	}
+
+	msg := "geo lookup failed"
+	if len(errs) > 0 {
+		msg = strings.Join(errs, "; ")
+	}
+	s.geoMu.Lock()
+	s.geoCache[ip] = egressGeoCacheEntry{
+		LastError: msg,
+		ExpiresAt: now.Add(egressIdentityGeoFailTTL),
+	}
+	s.geoMu.Unlock()
+	return "", "", fmt.Errorf("%s", msg)
+}