Clients

The clients plugin generates resource-based client classes and request commands from your Typeweaver spec. Instead of hand-writing URLs, payload types, and response parsing, you call your API through generated, contract-aware client code.

Install note

For client generation, add the plugin package:

npm install -D @rexeus/typeweaver-clients

What gets generated

For a todo resource with a getTodo operation, Typeweaver generates artifacts such as:

TodoClient
GetTodoRequestCommand
request and response types
request and response validators

Calling an operation

import { GetTodoRequestCommand, TodoClient } from "./api/generated";

const client = new TodoClient({
  baseUrl: "/api",
});

const response = await client.send(
  new GetTodoRequestCommand({
    param: {
      todoId: "todo_123",
    },
  }),
);

if (response.type === "GetTodoSuccess") {
  console.log(response.body.title);
}

baseUrl is required. fetchFn and timeoutMs are optional.

If your runtime already provides a global fetch, baseUrl is enough. Pass fetchFn only when you need a custom transport, such as in tests, on older Node.js setups, or inside a wrapper that decorates fetch.

The important part is the flow:

Create the generated client for the resource.
Create the generated request command for the operation.
Send the command.
Branch on response.type to handle the allowed outcomes.

Why this helps

Generated clients reduce contract drift because the caller uses artifacts built from the same spec as the server-side validators and handlers.

That means:

request shapes stay aligned with the spec
response handling stays aligned with the declared responses
renaming an operation or changing a schema shows up in generated code immediately

This page is about the generated surface

This page is about what the clients plugin generates. For constructor options and day-to-day calling patterns, see Basic Usage.

Most teams mainly work with:

the resource client, such as TodoClient
the request command for a specific operation
the response union returned by send(...)