Medplum React Hooks Library

The Medplum React Hooks Library provides non-UI React features for your application.

Most users will want the full Medplum React Component Library, @medplum/react. However, that library has peer dependencies on Mantine, which may not be desired.

Key Features

useMedplum - handles shared global instance of MedplumClient
useResource - reads a resource by ID or reference with intelligent caching
useSearch - performs a FHIR search with intelligent state management
useSubscription - subscribes to a FHIR search criteria and calls a given callback upon receiving a relevant notification

Installation

Add as a dependency:

npm install @medplum/react-hooks

Note the following peer dependencies:

Setup

import { MedplumClient } from '@medplum/core';
import { MedplumProvider } from '@medplum/react';

const medplum = new MedplumClient();

export function App() {
  return (
    <MedplumProvider medplum={medplum}>
      <MyPage1 />
      <MyPage2 />
      <Etc />
    </MedplumProvider>
  );
}

For more details on how to setup MedplumClient, refer to the docs for medplum.

`useMedplum`

import { useMedplum } from '@medplum/react-hooks';

export function MyComponent() {
  const medplum = useMedplum();
  return <div>{JSON.stringify(medplum.getProfile())}</div>;
}

`useMedplumContext`

useMedplumContext can be used to access the MedplumContext provided by the MedplumProvider directly. The MedplumContext has the following interface:

interface MedplumContext {
  medplum: MedplumClient;
  navigate: MedplumNavigateFunction;
  profile?: ProfileResource;
  loading: boolean;
}

Using `loading` to know when `MedplumClient` initialization is done

You can use the loading property from useMedplumContext() to know when MedplumClient has finished initialization successfully. loading is updated asynchronously so it will usually start as false and change to true once the client has finished its initialization.

function MyComponent(): JSX.Element {
  const { loading } = useMedplumContext();
  return loading ? <Spinner /> : <div>Loaded!</div>;
}

`useSubscription`

useSubscription creates an in-memory Subscription resource with the given criteria on the Medplum server and calls the given callback when an event notification is triggered by a resource interaction over a WebSocket connection.

Subscriptions created with this hook are lightweight, share a single WebSocket connection, and are automatically untracked and cleaned up when the containing component is no longer mounted.

function MyComponent(): JSX.Element {
  const [notificationCount, setNotificationCount] = useState(0);

  useSubscription('Communication?sender=Practitioner/abc-123&recipient=Practitioner/me-456', (bundle: Bundle) => {
    console.log('Received a message from Practitioner/abc-123!');
    handleNotificationBundle(bundle); // Do something with the bundle
    setNotificationCount((s) => s + 1);
  });

  return <div>Notifications received: {notificationCount}</div>;
}

Usage within `Expo` app

Usage within Expo / React Native has some special considerations. See: @medplum/expo-polyfills README

About Medplum

Medplum is a healthcare platform that helps you quickly develop high-quality compliant applications. Medplum includes a FHIR server, React component library, and developer app.