*** cdist #6: Glueing it together
**** Lecture content
***** Objective
      - Apply learnings from the previous cdist sessions
***** Steps 1: *__all_in_one* (1.25h)
      - Create a new type named *__all_in_one*
        - Decide yourself whether it is a singleton or not
        - Reason why in your cdist.org file
      - It should work on alpine, debian and fedora
      - It accepts the following parameters:
        - *--with-x* (boolean)
        - *--extra-packages* (optional multiple)
      - On Alpine, it should install netcat-openbsd and tshark
      - On Debian, it should install netcat tshark
      - On Fedora, it should install nmap-ncat wireshark-cli
      - On all operating systems install socat sipcalc sudo
      - If the detected operating system is neither
        Alpine/Debian/Fedora, output an error message and abort the
        manifest with exit code 1
      - Additionally install all packages specified by the *--extra-packages* parameter
***** Steps 2: *__firewall* (1.25h)
      - Create a new type *__my_firewall*
      - Add a *type explorer* to find out whether nft is present on
        the target system
      - Add a required parameter named *file*
      - If the type explorer does not detect nft on the target system,
        abort with an error message
      - Deploy the specified file to */etc/my-nftables*
      - Add a *type explorer* that reads the current nft rules
      - If the rules are different on the target host, apply the new
        ruleset by generating code in *gencode-remote*
      - If the filename specified by the *file* parameter is *-* (the
        minus sign), then the type should read from *stdin*
***** Step 3: manifest (0.5h)
      - Create a new manifest in the folder that contains the initial manifest
      - Name the new manifest *firewall*
      - Source the *firewall* manifest in the *initial* manifest
      - In the *firewall* manifest, match on *localhost*
        - Install nftables
        - Use the *__firewall* type
        - Use correct *require* parameter to ensure that nftables is
          installed before the *__firewall* type is run