wp-calypso/client/state/data-layer/wpcom-http/pipeline/retry-on-failure/index.jsx

import { get, merge } from 'lodash';
import { decorrelatedJitter as defaultDelay } from './delays';
import { default as defaultPolicy } from './policies';

const isGetRequest = ( request ) => 'GET' === get( request, 'method', '' ).toUpperCase();

export const retryOnFailure =
	( getDelay = defaultDelay ) =>
	( inboundData ) => {
		const {
			nextError,
			originalRequest,
			store: { dispatch },
		} = inboundData;

		// if the request came back successfully
		// then we have no need to intercept it
		// flush our records of it
		if ( ! nextError ) {
			return inboundData;
		}

		// otherwise check if we should try again
		if ( ! isGetRequest( originalRequest ) ) {
			return inboundData;
		}

		const { options: { retryPolicy: policy = defaultPolicy } = {} } = originalRequest;
		const { delay, maxAttempts, name } = policy;
		const retryCount = get( originalRequest, 'meta.dataLayer.retryCount', 0 ) + 1;

		if ( 'NO_RETRY' === name || retryCount > maxAttempts ) {
			return inboundData;
		}

		setTimeout(
			() => dispatch( merge( originalRequest, { meta: { dataLayer: { retryCount } } } ) ),
			getDelay( delay, retryCount )
		);

		return { ...inboundData, shouldAbort: true };
	};