Name request log actions so they say what they mean (closes #229)

Rename too_large, rate_limited, rule_blocked and denied, and split banned
into temporarily_banned and permanently_banned by whether the ban runs out.
A request that makes a ban permanent gets permanently_banned. A ban rule, a
trap path or a CrowdSec decision gets the value for the ban it makes, and in
observe mode would_action names the ban enforce mode would have made.

The offence kind rule_blocked follows, as a metric label and a key in
clients.json.

Model: opus-5-5

docs/request-log.md

@@ -100,8 +100,8 @@ Every one of these lines has:
       the action `deny`, or for a tag in `SWW_TAG_DENY`;
     - `temporarily_banned`: refused under a ban that runs out, or for a `ban`
       rule, a trap path or a CrowdSec decision that made such a ban;
-    - `permanently_banned`: refused under a ban that never runs out, or for a
-      request that made such a ban or made its client's ban permanent;
+    - `permanently_banned`: refused under a ban that never runs out, including a
+      ban this request made or made permanent;
     - `country_denied`, `client_is_rate_limited`, `blocked_by_block_rule` and
       `waf_blocked`: refused by that check;
     - `request_header_too_large`: over a header limit;

internal/discriminator/bans.go

@@ -100,8 +100,8 @@ func (rq *request) countedBytes() int64 {
 // rate limit or a byte limit; the error burst is not lowered. The ban sets
 // the client's counters back to zero. In observe mode it makes no ban and
 // sets nothing back, and raises the alert for the ban it would have made,
-// if that alert would be sent. It returns the action for that ban.
-func (rq *request) banForLimit(now time.Time, hit ratelimit.Hit, status int) string {
+// if that alert would be sent.
+func (rq *request) banForLimit(now time.Time, hit ratelimit.Hit, status int) {
 	switch hit.Kind {
 	case ratelimit.KindBytes:
 		rq.line.LimitHit = hit.Window + "_bytes" // as counts names the byte totals
@@ -116,7 +116,7 @@ func (rq *request) banForLimit(now time.Time, hit ratelimit.Hit, status int) str
 
 	netblock := rq.h.netblock(rq.client)
 	if rq.h.config.Observe && !rq.wouldAlertBan(netblock, now, bans.CauseLimit) {
-		return banAction(rq.h.ledger.WouldBePermanent(netblock, now, bans.CauseLimit))
+		return
 	}
 
 	notes := bans.Notes{
@@ -145,7 +145,7 @@ func (rq *request) banForLimit(now time.Time, hit ratelimit.Hit, status int) str
 			rq.alertBan(ban)
 		}
 
-		return banAction(ban.Permanent())
+		return
 	}
 
 	ban, made := rq.h.ledger.BanForLimit(netblock, now, notes)
@@ -155,8 +155,6 @@ func (rq *request) banForLimit(now time.Time, hit ratelimit.Hit, status int) str
 	if made {
 		rq.alertBan(ban)
 	}
-
-	return banAction(ban.Permanent())
 }
 
 // banForAttack bans the client's netblock at now for a clear sign of

internal/discriminator/bytelimits.go

@@ -35,7 +35,7 @@ func (byteLimits) check(_ context.Context, rq *request, now time.Time) *verdict
 		return nil
 	}
 
-	return &verdict{
-		action: rq.banForLimit(now, hit, rq.out.status), figures: limitFigures(hit),
-	}
+	rq.banForLimit(now, hit, rq.out.status)
+
+	return &verdict{figures: limitFigures(hit)}
 }

internal/discriminator/observe_test.go

@@ -7,6 +7,7 @@ import (
 	"testing"
 	"time"
 
+	"sneak.berlin/go/smallwebwaf/internal/alerts"
 	"sneak.berlin/go/smallwebwaf/internal/bans"
 	"sneak.berlin/go/smallwebwaf/internal/requestlog"
 )
@@ -78,6 +79,29 @@ func TestBanActionSaysWhetherTheBanRunsOut(t *testing.T) {
 	}
 }
 
+func TestObserveModeNamesAPermanentBanWhoseAlertWouldBeSent(t *testing.T) {
+	t.Parallel()
+
+	s, clk, server, queue := startWithAlerts(t, map[string]string{
+		trapPaths: trapPathList, mode: observe,
+	})
+
+	server.Ledger.Load([]bans.Ban{{
+		Netblock: netip.MustParsePrefix(client + "/32"),
+		Start:    clk.Now().Add(-2 * time.Hour),
+		Expires:  clk.Now().Add(-time.Hour),
+		Cause:    bans.CauseAttack,
+	}})
+
+	line := s.request(client, "/wp-login.php", http.StatusOK, requestlog.ActionForward)
+	wantWouldAction(t, line, requestlog.ActionPermanentlyBanned)
+
+	waiting := queue.Snapshot().Waiting[alerts.DestinationWebhook]
+	if len(waiting) != 1 || waiting[0].Event != alerts.EventPermanentBan {
+		t.Errorf("alerts waiting are %+v, want one %s", waiting, alerts.EventPermanentBan)
+	}
+}
+
 func TestObserveModeNamesTheHeuristicThatWouldHaveRefused(t *testing.T) {
 	t.Parallel()
 

internal/discriminator/refusallimit.go

@@ -48,5 +48,7 @@ func (refusalLimit) check(_ context.Context, rq *request, now time.Time) *verdic
 		status = cfg.BanResponse
 	}
 
-	return &verdict{action: rq.banForLimit(now, hit, status), figures: limitFigures(hit)}
+	rq.banForLimit(now, hit, status)
+
+	return &verdict{figures: limitFigures(hit)}
 }