Skip to content

Latest commit

 

History

History
60 lines (45 loc) · 2.22 KB

jwksCache.md

File metadata and controls

60 lines (45 loc) · 2.22 KB

Variable: jwksCache

💗 Help the project

Support from the community to continue maintaining and improving this module is welcome. If you find the module useful, please consider supporting the project by becoming a sponsor.

• const jwksCache: unique symbol

Warning

This option has security implications that must be understood, assessed for applicability, and accepted before use. It is critical that the JSON Web Key Set cache only be writable by your own code.

This option is intended for cloud computing runtimes that cannot keep an in memory cache between their code's invocations. Use in runtimes where an in memory cache between requests is available is not desirable.

When passed to createRemoteJWKSet this allows the passed in object to:

  • Serve as an initial value for the JSON Web Key Set that the module would otherwise need to trigger an HTTP request for
  • Have the JSON Web Key Set the function optionally ended up triggering an HTTP request for assigned to it as properties

The intended use pattern is:

  • Before verifying with createRemoteJWKSet you pull the previously cached object from a low-latency key-value store offered by the cloud computing runtime it is executed on;
  • Default to an empty object {} instead when there's no previously cached value;
  • Pass it in as [jwksCache];
  • Afterwards, update the key-value storage if the uat property of the object has changed.

Example

// Prerequisites
let url!: URL
let jwt!: string
let getPreviouslyCachedJWKS!: () => Promise<jose.ExportedJWKSCache>
let storeNewJWKScache!: (cache: jose.ExportedJWKSCache) => Promise<void>

// Load JSON Web Key Set cache
const jwksCache: jose.JWKSCacheInput = (await getPreviouslyCachedJWKS()) || {}
const { uat } = jwksCache

const JWKS = jose.createRemoteJWKSet(url, {
  [jose.jwksCache]: jwksCache,
})

// Use JSON Web Key Set cache
await jose.jwtVerify(jwt, JWKS)

if (uat !== jwksCache.uat) {
  // Update JSON Web Key Set cache
  await storeNewJWKScache(jwksCache)
}