fix(core): json escaping of some characters

src/Netstr/Extensions/JsonExtensions.cs → src/Netstr/Json/JsonExtensions.cs

@@ -1,6 +1,6 @@
 using System.Text.Json;
 
-namespace Netstr.Extensions
+namespace Netstr.Json
 {
     public static class JsonExtensions
     {

src/Netstr/Json/NostrJsonEncoder.cs

@@ -0,0 +1,29 @@
+using System.Text.Encodings.Web;
+
+namespace Netstr.Json
+{
+    /// <summary>
+    /// Json encoder for nostr events which follows NIP-01's character escaping rules.
+    /// </summary>
+    public class NostrJsonEncoder : JavaScriptEncoder
+    {
+        private static int[] EscapableCharacters = [0x0A, 0x22, 0x5C, 0x0D, 0x09, 0x08, 0x0C];
+
+        public override int MaxOutputCharactersPerInputCharacter => JavaScriptEncoder.Default.MaxOutputCharactersPerInputCharacter;
+
+        public override unsafe int FindFirstCharacterToEncode(char* text, int textLength)
+        {
+            return JavaScriptEncoder.UnsafeRelaxedJsonEscaping.FindFirstCharacterToEncode(text, textLength);
+        }
+
+        public override unsafe bool TryEncodeUnicodeScalar(int unicodeScalar, char* buffer, int bufferLength, out int numberOfCharactersWritten)
+        {
+            return JavaScriptEncoder.UnsafeRelaxedJsonEscaping.TryEncodeUnicodeScalar(unicodeScalar, buffer, bufferLength, out numberOfCharactersWritten);
+        }
+
+        public override bool WillEncode(int unicodeScalar)
+        {
+            return EscapableCharacters.Contains(unicodeScalar);
+        }
+    }
+}

src/Netstr/Converters/UnixTimestampJsonConverter.cs → src/Netstr/Json/UnixTimestampJsonConverter.cs

@@ -1,7 +1,7 @@
 using System.Text.Json.Serialization;
 using System.Text.Json;
 
-namespace Netstr.Converters
+namespace Netstr.Json
 {
     /// <summary>
     /// Converts Unix time to DateTimeOffset.

src/Netstr/Messaging/Events/EventParser.cs

@@ -1,4 +1,4 @@
-using Netstr.Extensions;
+using Netstr.Json;
 using Netstr.Messaging.Models;
 using System.Text.Json;
 

src/Netstr/Messaging/Events/Validators/EventHashValidator.cs

@@ -1,4 +1,5 @@
-using Netstr.Messaging.Models;
+using Netstr.Json;
+using Netstr.Messaging.Models;
 using System.Security.Cryptography;
 using System.Text.Encodings.Web;
 using System.Text.Json;
@@ -12,7 +13,7 @@ public class EventHashValidator : IEventValidator
     {
         private static JsonSerializerOptions serializerOptions = new JsonSerializerOptions
         {
-            Encoder = JavaScriptEncoder.UnsafeRelaxedJsonEscaping
+            Encoder = new NostrJsonEncoder()            
         };
 
         public string? Validate(Event e, ClientContext context)

src/Netstr/Messaging/MessageHandlers/FilterMessageHandlerBase.cs

@@ -1,6 +1,7 @@
 using Microsoft.Extensions.Options;
 using Netstr.Data;
 using Netstr.Extensions;
+using Netstr.Json;
 using Netstr.Messaging.Models;
 using Netstr.Messaging.Subscriptions;
 using Netstr.Messaging.Subscriptions.Validators;

src/Netstr/Messaging/MessageHandlers/UnsubscribeMessageHandler.cs

@@ -1,4 +1,4 @@
-using Netstr.Extensions;
+using Netstr.Json;
 using Netstr.Messaging.Models;
 using System.Text.Json;
 

src/Netstr/Messaging/Models/Event.cs

@@ -1,5 +1,5 @@
 using Microsoft.EntityFrameworkCore.Diagnostics;
-using Netstr.Converters;
+using Netstr.Json;
 using System.Numerics;
 using System.Text.Json.Serialization;
 

src/Netstr/Messaging/Models/SubscriptionFilter.cs

@@ -1,4 +1,4 @@
-using Netstr.Converters;
+using Netstr.Json;
 using System.Text.Json;
 using System.Text.Json.Serialization;
 

src/Netstr/Netstr.csproj

@@ -6,6 +6,7 @@
     <ImplicitUsings>enable</ImplicitUsings>
     <DockerDefaultTargetOS>Linux</DockerDefaultTargetOS>
 	<DockerfileFile>..\..\Dockerfile</DockerfileFile>
+	<AllowUnsafeBlocks>true</AllowUnsafeBlocks>
   </PropertyGroup>
 
   <ItemGroup>

test/Netstr.Tests/NIPs/01.feature

@@ -1,4 +1,4 @@
-Feature: NIP-01
+Feature: NIP-01
 	Defines the basic protocol that should be implemented by everybody. 
 
 Background: 
@@ -20,21 +20,21 @@ Scenario: Invalid messages are discarded, valid ones accepted
 	| Kinds |
 	| 1     |
 	And Bob publishes events
-	| Id                                                               | Content              | Kind | CreatedAt  | Signature | Tags |
-	| ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff | Hello 1              | 1    | 1722337838 |           |      |
-	| a6d166e834e78827af0770f31f15b13a772f281ad880f43ce12c24d4e3d0e346 | Hello 1              | 1    | 1722337838 | Invalid   |      |
-	| 9a6b4cefcd17f3bf7fb03c02da044c628836a118c47d5b92503c1d2bdb796296 | Hi ' \" \b \t \r \n  | 1    | 1722337838 |           |      |
-	| 50ed63c449df67d89e9964a27a26abbf214ca155b03915067a5a0f75618802bb | Hello                | 1    | 1722337838 |           | [[]] |
+	| Id                                                               | Content                       | Kind | CreatedAt  | Signature | Tags |
+	| ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff | Hello 1                       | 1    | 1722337838 |           |      |
+	| a6d166e834e78827af0770f31f15b13a772f281ad880f43ce12c24d4e3d0e346 | Hello 1                       | 1    | 1722337838 | Invalid   |      |
+	| bb5d2fe5b2c16c676d87ef446fa38581b9fa45e2e50ba89568664abf4e1d1396 | Hi ' \" \b \t \r \n 🎉 #nostr | 1    | 1722337838 |           |      |
+	| 50ed63c449df67d89e9964a27a26abbf214ca155b03915067a5a0f75618802bb | Hello                         | 1    | 1722337838 |           | [[]] |
 	Then Bob receives messages
  	| Type | Id                                                               | Success |
  	| OK   | ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff | false   |
  	| OK   | a6d166e834e78827af0770f31f15b13a772f281ad880f43ce12c24d4e3d0e346 | false   |
- 	| OK   | 9a6b4cefcd17f3bf7fb03c02da044c628836a118c47d5b92503c1d2bdb796296 | true    |
+ 	| OK   | bb5d2fe5b2c16c676d87ef446fa38581b9fa45e2e50ba89568664abf4e1d1396 | true    |
  	| OK   | 50ed63c449df67d89e9964a27a26abbf214ca155b03915067a5a0f75618802bb | false   |
 	And Alice receives a message
  	| Type  | Id   | EventId                                                          |
  	| EOSE  | abcd |                                                                  |
- 	| EVENT | abcd | 9a6b4cefcd17f3bf7fb03c02da044c628836a118c47d5b92503c1d2bdb796296 |
+ 	| EVENT | abcd | bb5d2fe5b2c16c676d87ef446fa38581b9fa45e2e50ba89568664abf4e1d1396 |
 
 Scenario: Newly subscribed client receives matching events, EOSE and future events
 	Bob publishes events which are stored by the relay before any subscription exists. 

test/Netstr.Tests/NIPs/Types.cs

@@ -1,4 +1,4 @@
-using Netstr.Extensions;
+using Netstr.Json;
 using Netstr.Messaging.Models;
 using System.Net.WebSockets;
 using System.Text.Json;