Error:
  badError:
    message:
      header:
        version: 4
        type: OFPT_ERROR
        length: 8
        xid: 0
    expectation: false
    description: error without type
  error:
    message:
      header:
        version: 4
        type: OFPT_ERROR
        length: 12
        xid: 0
      type: OFPET_HELLO_FAILED
      code: OFPHFC_INCOMPATIBLE
    expectation: true
    description: plain error