Cron expression doesn't work for scheduling functions

[lwang-79]

Environment information

System:
  OS: macOS 15.1.1
  CPU: (10) arm64 Apple M1 Pro
  Memory: 248.80 MB / 32.00 GB
  Shell: /bin/zsh
Binaries:
  Node: 22.9.0 - /opt/homebrew/bin/node
  Yarn: 1.22.19 - /opt/homebrew/bin/yarn
  npm: 10.8.3 - /opt/homebrew/bin/npm
  pnpm: undefined - undefined
NPM Packages:
  @aws-amplify/auth-construct: 1.5.1
  @aws-amplify/backend: 1.12.0
  @aws-amplify/backend-auth: 1.4.2
  @aws-amplify/backend-cli: 1.4.6
  @aws-amplify/backend-data: 1.4.0
  @aws-amplify/backend-deployer: 1.1.13
  @aws-amplify/backend-function: 1.11.0
  @aws-amplify/backend-output-schemas: 1.4.0
  @aws-amplify/backend-output-storage: 1.1.4
  @aws-amplify/backend-secret: 1.1.4
  @aws-amplify/backend-storage: 1.2.4
  @aws-amplify/cli-core: 1.2.1
  @aws-amplify/client-config: 1.5.5
  @aws-amplify/deployed-backend-client: 1.5.0
  @aws-amplify/form-generator: 1.0.3
  @aws-amplify/model-generator: 1.0.12
  @aws-amplify/platform-core: 1.5.0
  @aws-amplify/plugin-types: 1.7.0
  @aws-amplify/sandbox: 1.2.9
  @aws-amplify/schema-generator: 1.2.6
  aws-amplify: 6.6.2
  aws-cdk: 2.173.2
  aws-cdk-lib: 2.173.2
  typescript: 5.6.2
No AWS environment variables
No CDK environment variables

Describe the bug

The cron expressions described in this documentation doesn't work, and received the following error.

Failed to instantiate schedule for nodejs function
Caused By: Cron field for month must be a whole number between 1 and 12\nCron expressions cannot have both day-of-month and day-of-week defined, you must use a ? in one of the fields\nCron field for month must be a whole number between 1 and 12\nCron expressions cannot have both day-of-month and day-of-week defined, you must use a ? in one of the fields

It seems that the validateCron function doesn't accept the * wildcard.

Reproduction steps

Follow the documentation to set the schedule for a function.

[ykethan]

Hey @lwang-79, thank you for reaching out. This is currently being tracked on aws-amplify/docs#8180
we are working on updating this here: aws-amplify/docs#8181

The cron expression lets say every tuesday at 5pm should be0 17 ? * 3 * instead of 0 17 * ? 3 * .
closing this issue as this is currently being tracked on aws-amplify/docs#8180