DTK0020: RPC Function Not Registered

Package: @vitejs/devtools

Message

RPC function "{name}" is not registered

Cause

The RpcFunctionsHost.invokeLocal() method was called with a function name that has not been registered in the RPC definitions map. This method is used to call server-side RPC functions directly without going through the WebSocket transport. The function must have been registered via defineRpcFunction and collected by the RPC host before it can be invoked locally.

Example

export default defineDevToolsPlugin({
  name: 'my-plugin',
  setup(context) {
    // Attempting to invoke a function that hasn't been registered throws DTK0020
    await context.rpc.invokeLocal('my-plugin:unregistered-fn')
  },
})

Fix

Ensure the RPC function is registered before calling invokeLocal(). The function must be defined using defineRpcFunction and set up within a plugin that has already been initialized.

import { defineRpcFunction } from '@vitejs/devtools-kit'

// Define the function
export const myFunction = defineRpcFunction({
  name: 'my-plugin:my-function',
  type: 'query',
  setup: context => ({
    handler: () => {
      return { result: 'hello' }
    },
  }),
})

// Later, invoke it locally (after it has been registered)
const result = await context.rpc.invokeLocal('my-plugin:my-function')

Source

packages/core/src/node/host-functions.ts