EXPOSE ports not analysed correctly

[martinlobe]

In the docker expose instruction one can define what protocol too.

e.g.
EXPOSE 80/tcp 3000/udp

This is currently detected as a non valid port. Definition of the protocol is allowed.

This is maybe fixed by that:

  expose_port_valid: function(port) {
    return /^([0-9]{1,4}|[1-5][0-9]{4}|6[0-4][0-9]{3}|65[0-4][0-9]{2}|655[0-2][0-9]|6553[0-5])(\/tcp|\/udp){0,1}$/.test(port);
  },

This also checks for a valid port in range, since currently 99999999 is also detected as a valid port.

[thomasbiddle]

Along with this - it would be great to allow a variable to be referenced. I follow the practice of

ENV PORT=3000
EXPOSE $PORT

... (Use in other spots as well, to keep DRY)

Line 18: EXPOSE $PORT
Issue  Category      Title                 Description
    1  Possible Bug  Invalid Port Exposed  Exposing ports should only be valid port numbers.

[marccampbell]

@thomasbiddle Agreed. Will you open a new issue for the ENV PORT; EXPOSE $PORT pattern? I think we should add this in, but we should also do it correctly and ensure that the env var is set and still a valid value (when possible).

[thomasbiddle]

@marccampbell Referenced in #86.

[nexdrew]

Closing this as it should be fixed in version 1.3.0+. Please let us know if you still have problems with the "port/proto" syntax.

(Also note that fromlatest.io isn't currently running the latest version of dockerfilelint, see replicatedhq/fromlatest.io#242.)