json-joy

json-joy is a library designed for real-time and collaborative editing of JSON data models. Its primary focus is the implementation of the JSON CRDT protocol, a Conflict-free Replicated Data Type that allows multiple replicas to merge changes seamlessly without conflicts.

Beyond CRDTs, the library provides high-performance implementations for various JSON-related utilities, including codecs (CBOR, MessagePack, etc.), JSON Patch, JSON Schema validation, and JSON Expressions.

The @jsonjoy.com/rpc-client is a browser client for JSON Reactive RPC servers. It connects to an @jsonjoy.com/rpc-server instance over WebSocket or HTTP and provides the following capabilities:

• Transports: WebSocket and HTTP (fetch) via @jsonjoy.com/channel.
• Codecs: Support for Compact, Binary, and JSON-RPC 2.0.
• Reliability: Automatic reconnection via PersistentChannel.
• Type Safety: TypeScript-typed RPC calls.

The @jsonjoy.com/rpc-server package provides an HTTP/1.1 and WebSocket server that exposes Reactive JSON-RPC methods. It supports three RPC protocols (Compact, Binary, JSON-RPC 2.0) and three value codecs (JSON, CBOR, MessagePack) via content-type negotiation.

Available Backends

• Node http backend: Uses RpcServer or Http1Server (built on top of Node's http/https with a built-in WebSocket implementation).
• uWebSockets backend: Uses RpcApp (an alternative backend, often used for testing or high performance).

Per-request Data

• ConnectionContext: Used for managing per-request data, token extraction, and codec negotiation.

JSON Joy provides several CLI tools for manipulating and querying JSON documents:

• json-pack: Encodes a JSON document into MessagePack format.
• json-unpack: Decodes a JSON document from MessagePack format.
• json-pointer: Finds a specific value within a JSON document using JSON Pointer syntax.
• json-patch: Applies a JSON Patch to a JSON document.
• json-pack-test: Runs tests against the json-pack CLI.
• json-pointer-test: Runs tests against the json-pointer CLI.
• json-patch-test: Runs tests against the json-patch CLI.

The NFSv3 implementation in json-pack provides complete support for the RFC 1813 protocol, covering three distinct layers:

• NFSv3: Core NFS version 3 protocol operations.
• MOUNT: The Mount protocol (defined in Appendix I of RFC 1813).
• NLM: The Network Lock Manager protocol version 4 (defined in Appendix II of RFC 1813).

The @jsonjoy.com/rpc-server package provides a robust JSON RPC implementation with the following capabilities:

• Transport Support: HTTP/1.1 server with path-based routing (via @jsonjoy.com/jit-router) and WebSocket upgrade handling with a built-in frame codec (no external WS dependency).
• Security: TLS support with automatic secure context refresh, CORS support, and authentication token extraction from headers, query parameters, or cookies.
• Codec & Encoding:
  • RPC Codecs: Supports Compact, Binary, and JSON-RPC 2.0.
  • Value Encodings: Supports JSON, CBOR, and MessagePack.
  • Negotiation: Automatic codec negotiation based on the Content-type header.

The @jsonjoy.com/rpc-codec-base package provides the foundational types and utilities required to implement RPC (Remote Procedure Call) message codecs. It defines the core interfaces and constants used across the json-joy ecosystem for message serialization and streaming.

Key components include:

• MsgStreamCodec: An interface for codecs that handle message streams.
• MsgCodec: An interface for standard message codecs.
• RpcMessageFormat: Constants defining the supported codec formats.
• getTypeEncoder: A helper function used by codec implementations to handle type encoding.

import {RpcMessageFormat} from '@jsonjoy.com/rpc-codec-base';
import type {MsgStreamCodec} from '@jsonjoy.com/rpc-codec-base';

The json-type package provides JIT-compiled encoders for four wire formats: JSON text, JSON binary, CBOR, and MessagePack. Each encoder takes a type schema and produces a specialized function that writes data without per-call schema lookups.

Note: json-type only generates the encoders. For decoders, use the @jsonjoy.com/json-pack package.

import {t, JsonTextCodegen} from '@jsonjoy.com/json-type';

const User = t.Object(
  t.Key('id', t.str),
  t.Key('age', t.Number({format: 'u32'})),
);

const toJson = JsonTextCodegen.get(User);

toJson({id: 'u_1', age: 30});
// '{"id":"u_1","age":30}'