react-promise-wrapper v0.2.0

React promise wrapper.

Usage

Install via NPM or Yarn

npm install --save react-promise-wrapper

yarn add react-promise-wrapper

Write a component that will receive several props :

• loading: a boolean to indicate if promises are done.
• error: an error thrown if any of the promises fails
• Your promises names.

// MyComponent.js

const MyComponent = ({ loading, error, promiseData, anotherPromise }) => {
  if (loading) {
    return <span>Loading...</span>;
  }

  if (error) {
    return <span>Oups! Something went wrong</span>;
  }

  return (
    <div>
      <span>{promiseData.id}</span>
      <span>{anotherPromise}</span>
    </div>
  );
};

Then write a wrapper that will inject the promises thanks to the withPromises helper.

withPromises take an object as a first argument. This object's keys are the name of the props that will be injected into the wrapped component and their values are the promises that are to be resolved.

// WithPromiseComponent.js

// import the lib
import withPromises from 'react-promise-wrapper';

// import your component
import MyComponent from './MyComponent';

const WrappedComponent = withPromises({
  // `promiseData` will be injected as prop into MyComponent
  // when all promises will be resolved.
  promiseData: fetch('/data').then(res => res.json()),

  // Same for `anotherPromiseData`
  anotherPromiseData: Promise.resolve('random data'),
})(MyComponent);

You can also pass a function to withPromise, so that you are able to fetch multiple times as the component is updated. The above example would be modified to look like this:

const WrappedComponent = withPromises((props, oldProps, oldPromises) => ({
  user:
    props.id !== oldProps.id
      ? fetch(`/users/${props.id}`).then(res => res.json())
      : oldPromises.user,

  anotherPromiseData: Promise.resolve('random data'),
}))(MyComponent);