basic kind validation policy.

README.md

@@ -69,6 +69,11 @@ func main() {
 
 	// there are many other configurable things you can set
 	relay.RejectEvent = append(relay.RejectEvent,
+		// built-in policies
+		policies.ValidateKind,
+
+		// define your own policies
+		policies.PreventLargeTags(80),
 		func(ctx context.Context, event *nostr.Event) (reject bool, msg string) {
 			if event.PubKey == "fa984bd7dbb282f07e16e7ae87b26a2a7b9b90b7246a44771f0cf5ae58018f52" {
 				return true, "we don't allow this person to write here"
@@ -79,6 +84,10 @@ func main() {
 
 	// you can request auth by rejecting an event or a request with the prefix "auth-required: "
 	relay.RejectFilter = append(relay.RejectFilter,
+		// built-in policies
+		policies.NoComplexFilters,
+
+		// define your own policies
 		func(ctx context.Context, filter nostr.Filter) (reject bool, msg string) {
 			if pubkey := khatru.GetAuthed(ctx); pubkey != "" {
 				log.Printf("request from %s\n", pubkey)

examples/readme-demo/main.go

@@ -7,6 +7,7 @@ import (
 	"net/http"
 
 	"github.com/fiatjaf/khatru"
+	"github.com/fiatjaf/khatru/policies"
 	"github.com/nbd-wtf/go-nostr"
 )
 
@@ -53,6 +54,11 @@ func main() {
 
 	// there are many other configurable things you can set
 	relay.RejectEvent = append(relay.RejectEvent,
+		// built-in policies
+		policies.ValidateKind,
+
+		// define your own policies
+		policies.PreventLargeTags(80),
 		func(ctx context.Context, event *nostr.Event) (reject bool, msg string) {
 			if event.PubKey == "fa984bd7dbb282f07e16e7ae87b26a2a7b9b90b7246a44771f0cf5ae58018f52" {
 				return true, "we don't allow this person to write here"
@@ -63,6 +69,10 @@ func main() {
 
 	// you can request auth by rejecting an event or a request with the prefix "auth-required: "
 	relay.RejectFilter = append(relay.RejectFilter,
+		// built-in policies
+		policies.NoComplexFilters,
+
+		// define your own policies
 		func(ctx context.Context, filter nostr.Filter) (reject bool, msg string) {
 			if pubkey := khatru.GetAuthed(ctx); pubkey != "" {
 				log.Printf("request from %s\n", pubkey)

handlers.go

@@ -272,7 +272,6 @@ func (rl *Relay) HandleNIP11(w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Content-Type", "application/nostr+json")
 
 	info := *rl.Info
-
 	for _, ovw := range rl.OverwriteRelayInformation {
 		info = ovw(r.Context(), r, info)
 	}

policies/kind_validation.go

@@ -0,0 +1,29 @@
+package policies
+
+import (
+	"context"
+	"encoding/json"
+
+	"github.com/nbd-wtf/go-nostr"
+)
+
+func ValidateKind(ctx context.Context, evt *nostr.Event) (bool, string) {
+	switch evt.Kind {
+	case 0:
+		var m struct {
+			Name string `json:"name"`
+		}
+		json.Unmarshal([]byte(evt.Content), &m)
+		if m.Name == "" {
+			return true, "missing json name in kind 0"
+		}
+	case 1:
+		return false, ""
+	case 2:
+		return true, "this kind has been deprecated"
+	}
+
+	// TODO: all other kinds
+
+	return false, ""
+}

relay.go

@@ -2,7 +2,6 @@ package khatru
 
 import (
 	"context"
-	"fmt"
 	"log"
 	"net/http"
 	"os"
@@ -14,6 +13,32 @@ import (
 	"github.com/puzpuzpuz/xsync/v3"
 )
 
+func NewRelay() *Relay {
+	return &Relay{
+		Log: log.New(os.Stderr, "[khatru-relay] ", log.LstdFlags),
+
+		Info: &nip11.RelayInformationDocument{
+			Software:      "https://github.com/fiatjaf/khatru",
+			Version:       "n/a",
+			SupportedNIPs: []int{1, 11, 70},
+		},
+
+		upgrader: websocket.Upgrader{
+			ReadBufferSize:  1024,
+			WriteBufferSize: 1024,
+			CheckOrigin:     func(r *http.Request) bool { return true },
+		},
+
+		clients:  xsync.NewMapOf[*websocket.Conn, struct{}](),
+		serveMux: &http.ServeMux{},
+
+		WriteWait:      10 * time.Second,
+		PongWait:       60 * time.Second,
+		PingPeriod:     30 * time.Second,
+		MaxMessageSize: 512000,
+	}
+}
+
 type Relay struct {
 	ServiceURL string
 
@@ -34,7 +59,7 @@ type Relay struct {
 	OnEventSaved              []func(ctx context.Context, event *nostr.Event)
 	OnEphemeralEvent          []func(ctx context.Context, event *nostr.Event)
 
-	// editing info will affect the responses to the NIP-11 endpoint
+	// editing info will affect
 	Info *nip11.RelayInformationDocument
 
 	// Default logger, as set by NewServer, is a stdlib logger prefixed with "[khatru-relay] ",
@@ -57,49 +82,4 @@ type Relay struct {
 	PongWait       time.Duration // Time allowed to read the next pong message from the peer.
 	PingPeriod     time.Duration // Send pings to peer with this period. Must be less than pongWait.
 	MaxMessageSize int64         // Maximum message size allowed from peer.
-
-	// this context is used for all things inside the relay
-	Context context.Context
-	cancel  context.CancelCauseFunc
-}
-
-func NewRelay() *Relay {
-	return NewRelayWithContext(context.Background())
-}
-
-func NewRelayWithContext(ctx context.Context) *Relay {
-	ctx, cancel := context.WithCancelCause(ctx)
-
-	rl := &Relay{
-		Log: log.New(os.Stderr, "[khatru-relay] ", log.LstdFlags),
-
-		Info: &nip11.RelayInformationDocument{
-			Software:      "https://github.com/fiatjaf/khatru",
-			Version:       "n/a",
-			SupportedNIPs: []int{1, 11, 70},
-		},
-
-		upgrader: websocket.Upgrader{
-			ReadBufferSize:  1024,
-			WriteBufferSize: 1024,
-			CheckOrigin:     func(r *http.Request) bool { return true },
-		},
-
-		clients:  xsync.NewMapOf[*websocket.Conn, struct{}](),
-		serveMux: &http.ServeMux{},
-
-		WriteWait:      10 * time.Second,
-		PongWait:       60 * time.Second,
-		PingPeriod:     30 * time.Second,
-		MaxMessageSize: 512000,
-
-		Context: ctx,
-		cancel:  cancel,
-	}
-
-	return rl
-}
-
-func (rl *Relay) Close() {
-	rl.cancel(fmt.Errorf("Close called"))
 }

start.go

@@ -2,7 +2,6 @@ package khatru
 
 import (
 	"context"
-	"fmt"
 	"net"
 	"net/http"
 	"strconv"
@@ -49,8 +48,6 @@ func (rl *Relay) Start(host string, port int, started ...chan bool) error {
 
 // Shutdown sends a websocket close control message to all connected clients.
 func (rl *Relay) Shutdown(ctx context.Context) {
-	rl.cancel(fmt.Errorf("Shutdown called"))
-
 	rl.httpServer.Shutdown(ctx)
 
 	rl.clients.Range(func(conn *websocket.Conn, _ struct{}) bool {