All notable user-facing changes to this project will be documented in this file.

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

7.3.1

Fixed

  • Changed error displayed for the creationStack validation check when a store with localKeys set to false is used.
  • Improved documentation for the creationStack check.

7.3.0

Added

  • Added a new unsharedStore validation check that identifies cases where a single store instance is shared across multiple limiters.

7.2.0

Added

  • Added a new creationStack validation check that looks for instances created in a request handler.

7.1.5

Fixed

  • Enable async requestWasSuccessful methods to work as documented.

7.1.4

Fixed

  • Ensure header values are strings rather than numbers, for compatibility with Bun.

7.1.3

Changed

  • Loosened peer dependencies to explicitly allow the Express 5 beta. (See #415)

7.1.2

Changed

  • Re-organized documentation from readme into docs/ folder and added documentation website.

v7.1.1

Added

7.1.0

Changed

  • The getKey method is now always defined. If the store does not have the required get method, getKey will throw an error explaining this.

7.0.2

Added

  • Added cluster-memory-store to the readme and made a couple of other minor clarifications.

7.0.1

Added

  • Added rate-limit-postgresql to the stores list in the readme.

7.0.0

Breaking

  • Changed behavior when max is set to 0:
    • Previously, max: 0 was treated as a ‘disable’ flag and would allow all requests through.
    • Starting with v7, all requests will be blocked when max is set to 0.
    • To replicate the old behavior, use the skip function instead.
  • Renamed req.rateLimit.current to req.rateLimit.used.
    • current is now a hidden getter that will return the used value, but it will not appear when iterating over the keys or calling JSON.stringify().
  • Changed the minimum required Node version from v14 to v16.
    • express-rate-limit now targets es2022 in TypeScript/ESBuild.
  • Bumped TypeScript from v4 to v5 and dts-bundle-generator from v7 to v8.

Deprecated

  • Removed the draft_polli_ratelimit_headers option (it was deprecated in v6).
    • Use standardHeaders: 'draft-6' instead.
  • Removed the onLimitReached option (it was deprecated in v6).
    • This is an example of how to replicate it’s behavior with a custom handler option.

Changed

  • The MemoryStore now uses precise, per-user reset times rather than a global window that resets all users at once.
  • The limit configuration option is now preferred to max.
    • It still shows the same behavior, and max is still supported. The change was made to better align with terminology used in the IETF standard drafts.

Added

  • The validate config option can now be an object with keys to enable or disable specific validation checks. For more information, see this.

6.11.2

Fixed

  • Restored IncrementResponse TypeScript type (See #397)

6.11.1

Fixed

  • Check for prefixed keys when validating that the stores have single counted keys (See #395).

6.11.0

Added

  • Support for retrieving the current hit count and reset time for a given key from a store (See #390).

6.10.0

Added

  • Support for combined RateLimit header from the RateLimit header fields for HTTP standardization draft adopted by the IETF. Enable by setting standardHeaders: 'draft-7'.
  • New standardHeaders: 'draft-6' option, treated equivalent to standardHeaders: true from previous releases. Note that true and false are still supported.
  • New RateLimit-Policy header added when standardHeaders is set to 'draft-6', 'draft-7', or true.
  • Warning when using deprecated draft_polli_ratelimit_headers option.
  • Warning when using deprecated onLimitReached option.
  • Warning when totalHits value returned from Store is invalid.

6.9.0

Added

  • New validaion check for double-counted requests.
  • Added help link to each validation error, directing users to the appropriate wiki page for more info.

Changed

  • Miscellaneous documentation improvements.

6.8.1 & 6.7.2

Changed

  • Revert 6.7.1 change that bumped typescript from 5.x to 4.x and dts-bundle-generator from 8.x to 7.x (See #360).

6.8.0

Added

6.7.1

Fixed

  • Fixed compatibility with TypeScript’s TypeScript new node16 module resolution strategy (See #355).

Changed

  • Bumped development dependencies
    • This initially include bumping typescript from 4.x to 5.x and dts-bundle-generator from 7.x to 8.x
  • Added node 20 to list of versions the CI jobs run on.

No functional changes.

6.7.0

Changed

  • Updated links to point to the new express-rate-limit organization on GitHub.
  • Added advertisement to readme.md for project sponsor Zuplo.
  • Updated to typescript version 5 and bumped other dependencies.
  • Dropped node 12, and added node 19 to the list of versions the CI jobs run on.

No functional changes.

6.6.0

Added

  • Added shutdown method to the Store interface and the MemoryStore.

6.5.2

Fixed

  • Fixed an issue with missing types in ESM monorepos.

6.5.1

Added

  • The message option can now be a (sync/asynx) function that returns a value (#311)

Changed

  • Updated all dependencies

Note: 6.5.0 was not released due to CI automation issues.

6.4.0

Added

  • Adds Express 5 (5.0.0-beta.1) as a supported peer dependency (#304)

Changed

  • Tests are now run on Node 12, 14, 16 and 18 on CI (#305)
  • Updated all development dependencies (#306)

6.3.0

Changed

  • Changes the build target to es2019 so that ESBuild outputs code that can run with Node 12.
  • Changes the minimum required Node version to 12.9.0.

6.2.1

Fixed

  • Use the default value for an option when undefined is passed to the rate limiter.

6.2.0

Added

  • Export the MemoryStore, so it can now be imported as a named import (import { MemoryStore } from 'express-rate-limit').

Fixed

  • Deprecate the onLimitReached option (this was supposed to be deprecated in v6.0.0 itself); developers should use a custom handler function that checks if the rate limit has been exceeded instead.

6.1.0

Added

  • Added a named export rateLimit in case the default import does not work.

Fixed

  • Added a named export default, so Typescript CommonJS developers can default-import the library (import rateLimit from 'express-rate-limit').

6.0.5

Fixed

  • Use named imports for ExpressJS types so users do not need to enable the esModuleInterop flag in their Typescript compiler configuration.

6.0.4

Fixed

  • Upload the built package as a .tgz to GitHub releases.

Changed

  • Add main and module fields to package.json. This helps tools such as ESLint that do not yet support the exports field.
  • Bumped the minimum node.js version in package-lock.json to match package.json

6.0.3

Changed

6.0.2

Fixed

  • Ensure CommonJS projects can import the module.

Added

  • Add additional tests that test:
    • importing the library in js-cjs, js-esm, ts-cjs, ts-esm environments.
    • usage of the library with external stores (redis, mongo, memcached, precise).

Changed

  • Use esbuild to generate ESM and CJS output. This reduces the size of the built package from 138 kb to 13kb and build time to 4 ms! :rocket:
  • Use dts-bundle-generator to generate a single Typescript declaration file.

6.0.1

Fixed

  • Ensure CommonJS projects can import the module.

6.0.0

Added

  • express 4.x as a peer dependency.
  • Better Typescript support (the library was rewritten in Typescript).
  • Export the package as both ESM and CJS.
  • Publish the built package (.tgz file) on GitHub releases as well as the npm registry.
  • Issue and PR templates.
  • A contributing guide.

Changed

  • Rename the draft_polli_ratelimit_headers option to standardHeaders.
  • Rename the headers option to legacyHeaders.
  • Retry-After header is now sent if either legacyHeaders or standardHeaders is set.
  • Allow keyGenerator to be an async function/return a promise.
  • Change the way custom stores are defined.
    • Add the init method for stores to set themselves up using options passed to the middleware.
    • Rename the incr method to increment.
    • Allow the increment, decrement, resetKey and resetAll methods to return a promise.
    • Old stores will automatically be promisified and used.
  • The package can now only be used with NodeJS version 12.9.0 or greater.
  • The onLimitReached configuration option is now deprecated. Replace it with a custom handler that checks the number of hits.

Removed

  • Remove the deprecated limiter.resetIp method (use the limiter.resetKey method instead).
  • Remove the deprecated options delayMs, delayAfter (the delay functionality was moved to the express-slow-down package) and global (use a key generator that returns a constant value).

5.x

Added

  • The middleware throws logs an error if request.ip is undefined.

Removed

  • Removes typescript typings. (See #138)

4.x

Changed

  • The library no longer modifies the passed-in options object, it instead makes a clone of it.

3.x

Added

  • Simplifies the default handler function so that it no longer changes the response format. The default handler also uses response.send.

Changes

  • onLimitReached now only triggers once for a client and window. However, the handle method is called for every blocked request.

Removed

  • The delayAfter and delayMs options; they were moved to the express-slow-down package.

2.x

Added

  • Support external stores (from version 2.3.0) onwards.
  • A limiter.resetKey() method to reset the hit counter for a particular client

Changes

  • The rate limiter now uses a less precise but less resource intensive method of tracking hits from a client.

Removed

  • The global option.