diff options
Diffstat (limited to 'LibMatrix/Homeservers/ImplementationDetails/Synapse/Models/Responses/SynapseCollectionResult.cs')
| -rw-r--r-- | LibMatrix/Homeservers/ImplementationDetails/Synapse/Models/Responses/SynapseCollectionResult.cs | 250 |
1 files changed, 250 insertions, 0 deletions
diff --git a/LibMatrix/Homeservers/ImplementationDetails/Synapse/Models/Responses/SynapseCollectionResult.cs b/LibMatrix/Homeservers/ImplementationDetails/Synapse/Models/Responses/SynapseCollectionResult.cs new file mode 100644 index 0000000..36a5596 --- /dev/null +++ b/LibMatrix/Homeservers/ImplementationDetails/Synapse/Models/Responses/SynapseCollectionResult.cs @@ -0,0 +1,250 @@ +using System.Buffers; +using System.Text; +using System.Text.Json; +using System.Text.Json.Serialization; +using ArcaneLibs.Extensions; + +namespace LibMatrix.Homeservers.ImplementationDetails.Synapse.Models.Responses; + +public class SynapseNextTokenTotalCollectionResult { + [JsonPropertyName("total")] + public int Total { get; set; } + + [JsonPropertyName("next_token")] + public string? NextToken { get; set; } +} + +// [JsonConverter(typeof(SynapseCollectionJsonConverter<>))] +public class SynapseCollectionResult<T>(string chunkKey = "chunk", string prevTokenKey = "prev_token", string nextTokenKey = "next_token", string totalKey = "total") { + public int? Total { get; set; } + public string? PrevToken { get; set; } + public string? NextToken { get; set; } + public List<T> Chunk { get; set; } = []; + + // TODO: figure out how to provide an IAsyncEnumerable<T> for this + // https://learn.microsoft.com/en-us/dotnet/standard/serialization/system-text-json/use-utf8jsonreader#read-from-a-stream-using-utf8jsonreader + + // public async IAsyncEnumerable<T> FromJsonAsync(Stream stream) { + // + // } + + public SynapseCollectionResult<T> FromJson(Stream stream, Action<T> action) { + byte[] buffer = new byte[4096]; + _ = stream.Read(buffer); + var reader = new Utf8JsonReader(buffer, isFinalBlock: false, state: default); + + try { + FromJsonInternal(stream, ref buffer, ref reader, action); + } + catch (JsonException e) { + Console.WriteLine($"Caught a JsonException: {e}"); + int hexdumpWidth = 64; + Console.WriteLine($"Check hexdump line {reader.BytesConsumed / hexdumpWidth} index {reader.BytesConsumed % hexdumpWidth}"); + buffer.HexDump(64); + } + finally { } + + return this; + } + + private void FromJsonInternal(Stream stream, ref byte[] buffer, ref Utf8JsonReader reader, Action<T> action) { + while (!reader.IsFinalBlock) { + while (!reader.Read()) { + GetMoreBytesFromStream(stream, ref buffer, ref reader); + } + + if (reader.TokenType == JsonTokenType.PropertyName) { + var propName = reader.GetString(); + Console.WriteLine($"SynapseCollectionResult: encountered property name: {propName}"); + + while (!reader.Read()) { + GetMoreBytesFromStream(stream, ref buffer, ref reader); + } + + Console.WriteLine($"{reader.BytesConsumed}/{stream.Position} {reader.TokenType}"); + + if (propName == totalKey && reader.TokenType == JsonTokenType.Number) { + Total = reader.GetInt32(); + } + else if (propName == prevTokenKey && reader.TokenType == JsonTokenType.String) { + PrevToken = reader.GetString(); + } + else if (propName == nextTokenKey && reader.TokenType == JsonTokenType.String) { + NextToken = reader.GetString(); + } + else if (propName == chunkKey) { + if (reader.TokenType == JsonTokenType.StartArray) { + while (reader.Read() && reader.TokenType != JsonTokenType.EndArray) { + // if (reader.TokenType == JsonTokenType.EndArray) { + // break; + // } + // Console.WriteLine($"Encountered token in chunk: {reader.TokenType}"); + // var _buf = reader.ValueSequence.ToArray(); + // try { + // var item = JsonSerializer.Deserialize<T>(_buf); + // action(item); + // Chunk.Add(item); + // } + // catch(JsonException e) { + // Console.WriteLine($"Caught a JsonException: {e}"); + // int hexdumpWidth = 64; + // + // // Console.WriteLine($"Check hexdump line {reader.BytesConsumed / hexdumpWidth} index {reader.BytesConsumed % hexdumpWidth}"); + // Console.WriteLine($"Buffer length: {_buf.Length}"); + // _buf.HexDump(64); + // throw; + // } + var item = ReadItem(stream, ref buffer, ref reader); + action(item); + Chunk.Add(item); + } + } + } + } + } + } + + private T ReadItem(Stream stream, ref byte[] buffer, ref Utf8JsonReader reader) { + while (!reader.Read()) { + GetMoreBytesFromStream(stream, ref buffer, ref reader); + } + + // handle nullable types + if (typeof(T).IsGenericType && typeof(T).GetGenericTypeDefinition() == typeof(Nullable<>)) { + if (reader.TokenType == JsonTokenType.Null) { + return default(T); + } + } + + // if(typeof(T) == typeof(string)) { + // return (T)(object)reader.GetString(); + // } + // else if(typeof(T) == typeof(int)) { + // return (T)(object)reader.GetInt32(); + // } + // else { + // var _buf = reader.ValueSequence.ToArray(); + // return JsonSerializer.Deserialize<T>(_buf); + // } + + // default branch uses "object?" cast to avoid compiler error + // add more branches here as nessesary + // reader.Read(); + var call = typeof(T) switch { + Type t when t == typeof(string) => reader.GetString(), + _ => ReadObject<T>(stream, ref buffer, ref reader) + }; + + object ReadObject<T>(Stream stream, ref byte[] buffer, ref Utf8JsonReader reader) { + if (reader.TokenType != JsonTokenType.PropertyName) { + throw new JsonException(); + } + + List<byte> objBuffer = [(byte)'{', ..reader.ValueSequence.ToArray()]; + var currentDepth = reader.CurrentDepth; + while (reader.CurrentDepth >= currentDepth) { + while (!reader.Read()) { + GetMoreBytesFromStream(stream, ref buffer, ref reader); + } + + if (reader.TokenType == JsonTokenType.EndObject && reader.CurrentDepth == currentDepth) { + break; + } + + objBuffer.AddRange(reader.ValueSpan); + } + + return JsonSerializer.Deserialize<T>(objBuffer.ToArray()); + } + + return (T)call; + + // return JsonSerializer.Deserialize<T>(ref reader); + } + + private static void GetMoreBytesFromStream(Stream stream, ref byte[] buffer, ref Utf8JsonReader reader) { + int bytesRead; + if (reader.BytesConsumed < buffer.Length) { + ReadOnlySpan<byte> leftover = buffer.AsSpan((int)reader.BytesConsumed); + + if (leftover.Length == buffer.Length) { + Array.Resize(ref buffer, buffer.Length * 2); + Console.WriteLine($"Increased buffer size to {buffer.Length}"); + } + + leftover.CopyTo(buffer); + bytesRead = stream.Read(buffer.AsSpan(leftover.Length)); + } + else { + bytesRead = stream.Read(buffer); + } + + // Console.WriteLine($"String in buffer is: {Encoding.UTF8.GetString(buffer)}"); + reader = new Utf8JsonReader(buffer, isFinalBlock: bytesRead == 0, reader.CurrentState); + } +} + +public partial class SynapseCollectionJsonConverter<T> : JsonConverter<SynapseCollectionResult<T>> { + public override SynapseCollectionResult<T>? Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options) { + if (reader.TokenType != JsonTokenType.StartObject) { + throw new JsonException(); + } + + var result = new SynapseCollectionResult<T>(); + while (reader.Read()) { + if (reader.TokenType == JsonTokenType.EndObject) { + break; + } + + if (reader.TokenType != JsonTokenType.PropertyName) { + throw new JsonException(); + } + + var propName = reader.GetString(); + reader.Read(); + if (propName == "total") { + result.Total = reader.GetInt32(); + } + else if (propName == "prev_token") { + result.PrevToken = reader.GetString(); + } + else if (propName == "next_token") { + result.NextToken = reader.GetString(); + } + else if (propName == "chunk") { + if (reader.TokenType != JsonTokenType.StartArray) { + throw new JsonException(); + } + + while (reader.Read()) { + if (reader.TokenType == JsonTokenType.EndArray) { + break; + } + + var item = JsonSerializer.Deserialize<T>(ref reader, options); + result.Chunk.Add(item); + } + } + } + + return result; + } + + public override void Write(Utf8JsonWriter writer, SynapseCollectionResult<T> value, JsonSerializerOptions options) { + writer.WriteStartObject(); + if (value.Total is not null) + writer.WriteNumber("total", value.Total ?? 0); + if (value.PrevToken is not null) + writer.WriteString("prev_token", value.PrevToken); + if (value.NextToken is not null) + writer.WriteString("next_token", value.NextToken); + + writer.WriteStartArray("chunk"); + foreach (var item in value.Chunk) { + JsonSerializer.Serialize(writer, item, options); + } + + writer.WriteEndArray(); + writer.WriteEndObject(); + } +} \ No newline at end of file |