Office Whisperer

export function memoizeChain(providers, treatAsExpired) { const chain = internalCreateChain(providers); let activeLock; let passiveLock; let credentials; const provider = async (options) => { if (options?.forceRefresh) { return await chain(options); } if (credentials?.expiration) { if (credentials?.expiration?.getTime() < Date.now()) { credentials = undefined; } } if (activeLock) { await activeLock; } else if (!credentials || treatAsExpired?.(credentials)) { if (credentials) { if (!passiveLock) { passiveLock = chain(options).then((c) => { credentials = c; passiveLock = undefined; }); } } else { activeLock = chain(options).then((c) => { credentials = c; activeLock = undefined; }); return provider(options); } } return credentials; }; return provider; } export const internalCreateChain = (providers) => async (awsIdentityProperties) => { let lastProviderError; for (const provider of providers) { try { return await provider(awsIdentityProperties); } catch (err) { lastProviderError = err; if (err?.tryNextLink) { continue; } throw err; } } throw lastProviderError; };