@ariestools/json-rpc-engine

Browser-safe re-export of @metamask/json-rpc-engine v2 that tree-shakes the legacy events drag-along

Why this package?

@metamask/json-rpc-engine/v2 re-exports asLegacyMiddleware, which statically imports the legacy v1 engine → @metamask/safe-event-emitter → bare events. Browser consumers then need a bundler alias/polyfill for Node's events module even when they only use the v2 API.

This package re-exports the public v2 API without asLegacyMiddleware, and inlines the engine at compile time so the unused legacy chain is tree-shaken out of the published dist. Node and browser behavior for the v2 surface is unchanged.

Install

pnpm add @ariestools/json-rpc-engine

Usage

Drop-in for @metamask/json-rpc-engine/v2:

import {
  JsonRpcEngineV2,
  JsonRpcServer,
  createScaffoldMiddleware,
} from '@ariestools/json-rpc-engine'

// or, for a 1:1 path migration:
// import { JsonRpcEngineV2 } from '@ariestools/json-rpc-engine/v2'

const engine = JsonRpcEngineV2.create({
  middleware: [
    createScaffoldMiddleware({
      eth_chainId: () => '0x1',
    }),
  ],
})

Not exported

• asLegacyMiddleware — intentionally omitted (this is the events drag path)
• The legacy v1 root API (JsonRpcEngine, createAsyncMiddleware, …) — use MetaMask's package directly if you need v1 on Node only

Provenance

Runtime code is derived from @metamask/json-rpc-engine (ISC). Type re-exports still resolve against that package at publish time.

License

See the LICENSE file for license rights and limitations (LGPL-3.0-only). Bundled MetaMask engine code remains under its ISC license.