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Upgrade 3.x -> 4.x

aka "The AWS SDK v3 Update"

Version 4.x of Middy no longer supports Node.js versions 14.x. You are highly encouraged to move to Node.js 18.x.

Notable changes​

  • Middy now uses AWS SDK v3 by default.

Core​

  • Remove polyfill for AbortControler
  • Remove polyfill for timers/promises

Util​

  • normalizeResponse now will set the statusCode to 200 when casting to a new object or 500 when missing Breaking Change

Middleware​

cloudwatch-metrics​

No change

do-not-wait-for-empty-event-loop​

No change

error-logger​

No change

event-normalizer​

No change

http-content-encoding​

  • Removed body as stream support, will be brought back as a new middleware in a future middleware Breaking Change

http-content-negotiation​

No change

http-cors​

No change

http-error-handler​

No change

http-event-normalizer​

No change

http-header-normalizer​

No change

http-json-body-parser​

  • Deprecate event.rawBody Breaking Change

You can add in an inline middleware as a workaround.

  .before((request) => {
    request.event.rawBody = request.event.body
  })
  .use(httpJSONBodyParserMiddleware())

See https://github.com/middyjs/middy/issues/945 for discussion and reasoning.

http-multipart-body-parser​

  • Add new option to set charset

http-partial-response​

No change

http-response-serializer​

No change

http-router​

No change

http-security-headers​

No change

http-urlencode-body-parser​

  • Now throws 422 when unable to parse JSON Breaking Change

http-urlencode-path-parser​

No change

input-output-logger​

No change

rds-signer​

  • Updated to use AWS SDK v3 Breaking Change

s3-object-response​

  • Updated to use AWS SDK v3 Breaking Change

secrets-manager​

  • Updated to use AWS SDK v3 Breaking Change

service-discovery​

  • Updated to use AWS SDK v3 Breaking Change

sqs-partial-batch-failure​

No change

ssm​

  • Updated to use AWS SDK v3 Breaking Change

sts​

  • Updated to use AWS SDK v3 Breaking Change

validator​

We've put a lot of work into making this middleware bundle smaller and faster by default, while allowing for opting into more functionality.

  • Deprecate inputSchema and outputSchema options Breaking Change
  • Deprecated i18nEnabled Breaking Change
  • Must now pass in defaultLanguage localizations to languages Breaking Change
  • Added in ajv-error support
  • Pulled transpileSchema out of middleware to allow for tree shaking and pre-compile option Breaking Change
  • Added in transpileLocale to allow for custom internationalization of error messages including errorMessage

How to update use of middleware

import validatorMiddleware from '@middy/validator'
// 1. Import transpileSchema
import { transpileSchema } from '@middy/validator/transpile'

export const handler = middy(...)
  .use(validatorMiddleware({
    // 2. Wrap schemas with transpileSchema
    eventSchema: transpileSchema(eventJsonSchema)
  }))
import validatorMiddleware from '@middy/validator'
// 1. Import localizations
import { en, fr } from 'ajv-ftl-i18n'

export const handler = middy(...)
  .use(validatorMiddleware({
    eventSchema: transpileSchema(eventJsonSchema),
    // 2. Add localizations in
    langauges: { en, fr }
  }))

warmup​

No change

ws-json-body-parser​

No change

ws-response​

  • Updated to use AWS SDK v3 Breaking Change

ws-router​

No change

Notes​

None