v4.0.0

Breaking Changes

• Deprecated allowInvalidAppCheckToken option. Instead use
  enforceAppCheck.

App Check enforcement on callable functions is disabled by default in v4.
Requests containing invalid App Check tokens won't be denied unless you
explicitly enable App Check enforcement using the new enforceAppCheck option.
Furthermore, when enforcement is enabled, callable functions will deny
all requests without App Check tokens.

• Dropped support for Node.js versions 8, 10, and 12.
• Dropped support for Admin SDK versions 8 and 9.
• Removed the functions.handler namespace.
• DataSnapshot passed to the Firebase Realtime Database trigger now
  matches the DataSnapshot returned by the Admin SDK, with null values
  removed.
• Removed __trigger object on function handlers.
• Reorganized source code location. This affects only apps that directly import files instead of using the recommend entry points specified in the
• Reworked the apps library and removed lodash as a runtime dependency.
• Change default behavior of function deploy to clear configurations not specified in the source code (e.g. change memory configuration in Google Cloud Console). Use preserveExternalChanges to keep existing behavior. See docs for more info.

Enhancements

• Logs created with the functions.logger package in v2 functions
  are now annotated with each request's trace ID, making it easy to correlate
  log entries with the incoming request. Trace IDs are especially useful for
  cases where 2nd gen's concurrency feature permits a function
  to handle multiple requests at any given time. See
  Correlate log entries to learn more.
• functions.logger.error now always outputs an error object and is included in Google Cloud Error Reporting.
• The logging severity of Auth/App Check token validation has changed from info to debug level.
• Event parameters for 2nd generation functions are now strongly typed, permitting stronger TypeScript types for matched parameters.