Authn: Anon session service (#63052)

* add anon sessions package * add usage stat fn * implement count for cache * add anonservice to authn broker * lint * add tests for remote cache count * move anon service to services * wrap tagging in goroutine * make func used
2023-02-21 16:21:18 +01:00
parent 56c8661929
commit ff78103a24
21 changed files with 331 additions and 56 deletions
@@ -0,0 +1,91 @@
+package anonimpl
+
+import (
+	"context"
+	"encoding/hex"
+	"fmt"
+	"hash/fnv"
+	"net/http"
+	"strings"
+	"time"
+
+	"github.com/grafana/grafana/pkg/infra/log"
+	"github.com/grafana/grafana/pkg/infra/network"
+	"github.com/grafana/grafana/pkg/infra/remotecache"
+	"github.com/grafana/grafana/pkg/infra/usagestats"
+	"github.com/grafana/grafana/pkg/web"
+)
+
+const thirtyDays = 30 * 24 * time.Hour
+const anonCachePrefix = "anon-session"
+
+type AnonSession struct {
+	ip        string
+	userAgent string
+}
+
+func (a *AnonSession) Key() (string, error) {
+	key := strings.Builder{}
+	key.WriteString(a.ip)
+	key.WriteString(a.userAgent)
+
+	hash := fnv.New128a()
+	if _, err := hash.Write([]byte(key.String())); err != nil {
+		return "", fmt.Errorf("failed to write to hash: %w", err)
+	}
+
+	return strings.Join([]string{anonCachePrefix, hex.EncodeToString(hash.Sum(nil))}, ":"), nil
+}
+
+type AnonSessionService struct {
+	remoteCache remotecache.CacheStorage
+	log         log.Logger
+}
+
+func ProvideAnonymousSessionService(remoteCache remotecache.CacheStorage, usageStats usagestats.Service) *AnonSessionService {
+	a := &AnonSessionService{
+		remoteCache: remoteCache,
+		log:         log.New("anonymous-session-service"),
+	}
+
+	usageStats.RegisterMetricsFunc(a.UsageStatFn)
+
+	return a
+}
+
+func (a *AnonSessionService) UsageStatFn(ctx context.Context) (map[string]interface{}, error) {
+	sessionCount, err := a.remoteCache.Count(ctx, anonCachePrefix)
+	if err != nil {
+		return nil, nil
+	}
+
+	return map[string]interface{}{
+		"stats.anonymous.session.count": sessionCount,
+	}, nil
+}
+
+func (a *AnonSessionService) TagSession(ctx context.Context, httpReq *http.Request) error {
+	addr := web.RemoteAddr(httpReq)
+	ip, err := network.GetIPFromAddress(addr)
+	if err != nil {
+		a.log.Debug("failed to parse ip from address", "addr", addr)
+		return nil
+	}
+
+	clientIPStr := ip.String()
+	if len(ip) == 0 {
+		clientIPStr = ""
+	}
+
+	anonSession := &AnonSession{
+		ip:        clientIPStr,
+		userAgent: httpReq.UserAgent(),
+	}
+
+	key, err := anonSession.Key()
+	if err != nil {
+		return err
+	}
+
+	return a.remoteCache.Set(ctx, key, key, thirtyDays)
+}