From 9b22ea3ee68db6886e84e6c786c9552b9c23b4b8 Mon Sep 17 00:00:00 2001
From: fiatjaf <fiatjaf@gmail.com>
Date: Fri, 22 Dec 2023 19:51:35 -0300
Subject: [PATCH] fail properly when a storage function errors and other fixes
 related to prefixed reason messages.

---
 add-event.go | 15 ++++++---------
 handlers.go  | 19 +++++++++----------
 helpers.go   |  3 ---
 serve-req.go |  6 +++---
 4 files changed, 18 insertions(+), 25 deletions(-)

diff --git a/add-event.go b/add-event.go
index 6587d96..1c3eeba 100644
--- a/add-event.go
+++ b/add-event.go
@@ -2,6 +2,7 @@ package khatru
 
 import (
 	"context"
+	"errors"
 	"fmt"
 
 	"github.com/fiatjaf/eventstore"
@@ -10,15 +11,16 @@ import (
 
 func (rl *Relay) AddEvent(ctx context.Context, evt *nostr.Event) error {
 	if evt == nil {
-		return fmt.Errorf("event is nil")
+		return errors.New("error: event is nil")
 	}
 
 	for _, reject := range rl.RejectEvent {
 		if reject, msg := reject(ctx, evt); reject {
 			if msg == "" {
-				msg = "no reason"
+				return errors.New("blocked: no reason")
+			} else {
+				return errors.New(nostr.NormalizeOKMessage(msg, "blocked"))
 			}
-			return fmt.Errorf(msg)
 		}
 	}
 
@@ -63,12 +65,7 @@ func (rl *Relay) AddEvent(ctx context.Context, evt *nostr.Event) error {
 				case eventstore.ErrDupEvent:
 					return nil
 				default:
-					errmsg := saveErr.Error()
-					if nip20prefixmatcher.MatchString(errmsg) {
-						return saveErr
-					} else {
-						return fmt.Errorf("error: failed to save (%s)", errmsg)
-					}
+					return fmt.Errorf(nostr.NormalizeOKMessage(saveErr.Error(), "error"))
 				}
 			}
 		}
diff --git a/handlers.go b/handlers.go
index 5e3bbf9..9ec3e30 100644
--- a/handlers.go
+++ b/handlers.go
@@ -6,7 +6,7 @@ import (
 	"crypto/sha256"
 	"encoding/hex"
 	"encoding/json"
-	"fmt"
+	"errors"
 	"net/http"
 	"strings"
 	"sync"
@@ -135,20 +135,21 @@ func (rl *Relay) HandleWebsocket(w http.ResponseWriter, r *http.Request) {
 					}
 
 					var ok bool
+					var writeErr error
 					if env.Event.Kind == 5 {
-						err = rl.handleDeleteRequest(ctx, &env.Event)
+						// this always returns "blocked: " whenever it returns an error
+						writeErr = rl.handleDeleteRequest(ctx, &env.Event)
 					} else {
-						err = rl.AddEvent(ctx, &env.Event)
+						// this will also always return a prefixed reason
+						writeErr = rl.AddEvent(ctx, &env.Event)
 					}
 
-					var reason string
-					if err == nil {
+					reason := writeErr.Error()
+					if writeErr == nil {
 						ok = true
 					} else {
 						if strings.HasPrefix(reason, "auth-required:") {
 							ws.WriteJSON(nostr.AuthEnvelope{Challenge: &ws.Challenge})
-						} else {
-							reason = nostr.NormalizeOKMessage(err.Error(), "blocked")
 						}
 					}
 					ws.WriteJSON(nostr.OKEnvelope{EventID: env.Event.ID, OK: ok, Reason: reason})
@@ -177,11 +178,9 @@ func (rl *Relay) HandleWebsocket(w http.ResponseWriter, r *http.Request) {
 							reason := err.Error()
 							if strings.HasPrefix(reason, "auth-required:") {
 								ws.WriteJSON(nostr.AuthEnvelope{Challenge: &ws.Challenge})
-							} else {
-								reason = nostr.NormalizeOKMessage(reason, "blocked")
 							}
 							ws.WriteJSON(nostr.ClosedEnvelope{SubscriptionID: env.SubscriptionID, Reason: reason})
-							cancelReqCtx(fmt.Errorf("filter rejected"))
+							cancelReqCtx(errors.New("filter rejected"))
 							return
 						}
 					}
diff --git a/helpers.go b/helpers.go
index 5e08da8..888b4c6 100644
--- a/helpers.go
+++ b/helpers.go
@@ -3,7 +3,6 @@ package khatru
 import (
 	"hash/maphash"
 	"net/http"
-	"regexp"
 	"strconv"
 	"strings"
 	"unsafe"
@@ -16,8 +15,6 @@ const (
 	WS_KEY
 )
 
-var nip20prefixmatcher = regexp.MustCompile(`^\w+: `)
-
 func pointerHasher[V any](_ maphash.Seed, k *V) uint64 {
 	return uint64(uintptr(unsafe.Pointer(k)))
 }
diff --git a/serve-req.go b/serve-req.go
index ee63fbc..2ec5c03 100644
--- a/serve-req.go
+++ b/serve-req.go
@@ -2,7 +2,7 @@ package khatru
 
 import (
 	"context"
-	"fmt"
+	"errors"
 	"sync"
 
 	"github.com/nbd-wtf/go-nostr"
@@ -18,7 +18,7 @@ func (rl *Relay) handleRequest(ctx context.Context, id string, eose *sync.WaitGr
 	}
 
 	if filter.Limit < 0 {
-		return fmt.Errorf("filter invalidated")
+		return errors.New("blocked: filter invalidated")
 	}
 
 	// then check if we'll reject this filter (we apply this after overwriting
@@ -28,7 +28,7 @@ func (rl *Relay) handleRequest(ctx context.Context, id string, eose *sync.WaitGr
 	for _, reject := range rl.RejectFilter {
 		if reject, msg := reject(ctx, filter); reject {
 			ws.WriteJSON(nostr.NoticeEnvelope(msg))
-			return fmt.Errorf(msg)
+			return errors.New(nostr.NormalizeOKMessage(msg, "blocked"))
 		}
 	}