Label <label> is not a valid email format - must be conform to RFC5322.

This rule is activated by specifying a label-schema including a label of type email. This can be done via command line

$ hadolint --require-label maintainer:email Dockerfile

or in the config file:

label-schema:
  maintainer: email

Problematic code:

LABEL maintainer="foo-bar"

Correct code:

LABEL maintainer="foo@bar.com"

Note:

This rule does not expand variables. It requires the value of a label to be a literal email compliant with RFC 5322.