@visma/react-openapi-client-generator

Generate typed hooks and methods for React app from OpenAPI schema.

TodoMVC example

Setup in Create React App

1. Install: npm i @visma/react-openapi-client-generator

2. Add API schema JSON, e.g. src/petstore.json (examples)

3. Add scripts to package.json:

   JavaScript:

   "generate-client": "react-openapi-client-generator src/petstore.json src/client.js",
   "prestart": "npm run generate-client",
   "prebuild": "npm run generate-client",

   TypeScript:

   "generate-client": "react-openapi-client-generator src/petstore.json src/client.ts",
   "prestart": "npm run generate-client",
   "prebuild": "npm run generate-client",

4. Add .gitignore

   # generated
   /src/client.js

5. Use <Suspense> to show a loading indicator(s)

6. Use Error Boundary to handle errors

Options

--add-loaders

Include the API schema in the bundle. Example: react-openapi-client-generator src/petstore.json src/client.ts --add-loaders.

This will prefix the import path with !json-loader! and with yaml-loader! in case of YAML schema.

Hooks for data fetching

Each GET operation is available as a hook. Hooks return the response data directly. This is the main approach to fetch data for rendering. Requests are memoized, so it is fine to call the hooks in any component, right where the data is needed.

import { useItems } from './client';

function List() {
  const items = useItems();
  // ...
}

Mutations and updates

After updating the the data in the backend, the UI must be notified to refetch certain paths. For this there are refetch* methods for each GET operation (hook). Calling refetch does nothing if there are no components currently mounted using the corresponding hooks. This means it is safe to call refetch* just in case, whenever the data has been mutated. It is recommended to put these "mutation / what needs to be refetch" rules to a separate file, for example api.js:

import * as client from './client';

export * from './client';

export async function postItem(item) {
  await client.postItem(null, item);

  // Trigger refetching GET /items and rerendering components using
  // `useItems()`.
  // Does nothing, if there are no components mounted using `useItems()`.
  await client.refetchItems();

  // Multiple refetch calls in parallel:
  // await Promise.all([client.refetchX(), client.refetchY(), client.refetchZ()]);
}
// ...

Parameters

See openapi-client-axios documentation for Parameters.

Server-side Rendering

See https://www.npmjs.com/package/@postinumero/use-async#server-side-rendering.

FAQ

How to call hooks conditionally?

It is not allowed by the Rules of Hooks. Instead create a new component and render components conditionally. For example create <Search> component for <input> and query state. Render <SearchResults query={query} /> only when the query is available. The hook can be called unconditionally in SearchResults.

What if the request fails?

You may use react-error-boundary for general error handling. If you make request to an endpoint that may intentionally fail and you need to handle the error in the same component, each hook has a *Safe version for that. For example a search response may have status code 404 and we don't want to use the general error boundary for that:

import { useSearchSafe } from './client';

function SearchResults({ query }) {
  const [
    error, // null | axios error
    data, // undefined | axios response.data
  ] = useSearchSafe({ query });

  if (error) {
    // ...
  }
  // ...
}

How to access response headers?

There are *Raw versions of the hooks and API methods for accessing the complete axios response:

import { useFooRaw, postFooRaw } from './client';

function App() {
  const { headers, data } = useFooRaw();

  async function handleSubmit(data) {
    const { headers, data } = await postFooRaw(null, data);
  }
  // ...
}