enigma-bbs/docs/configuration/menu-hjson.md

layout	title
page	Menu HSJON

Menu HJSON

The core of a ENiGMA½ based BBS is it's menus driven by what will be referred to as menu.hjson. Throughout ENiGMA½ documentation, when menu.hjson is referenced, we're actually talking about config/menus/yourboardname-*.hjson. These files determine the menus (or screens) a user can see, the order they come in, how they interact with each other, ACS configuration, and so on. Like all configuration within ENiGMA½, menu configuration is done in HJSON format.

ℹ️ See also HJSON General Information for more information on the HJSON file format.

💡 Entries in menu.hjson are often referred to as blocks or sections. Each entry defines a menu. A menu in this sense is something the user can see or visit. Examples include but are not limited to:

• Classical navigation and menus such as Main, Messages, and Files.
• Art file display.
• Module driven menus such as door launchers, Onelinerz, and other custom mods.

Menu entries live under the menus section of menu.hjson. The key for a menu is it's name that can be referenced by other menus and areas of the system.

Below is a very basic menu entry called showSomeArt that displays some art then returns to the previous menu after the user hits a key:

showSomeArt: {
  art: someart.ans
  config: { pause: true }
}

As you can see a menu can be very simple.

ℹ️ Remember that the top level menu may include additional files using the includes directive. See Configuration Files for more information on this.

Common Menu Entry Members

Below is a table of common menu entry members. These members apply to most entries, though entries that are backed by a specialized module (ie: module: bbs_list) may differ. Menus that use their own module contain a module declaration:

module: some_fancy_module

See documentation for the module in question for particulars.

Item	Description
desc	A friendly description that can be found in places such as "Who's Online" or wherever the %MD MCI code is used.
art	An art file spec. See General Art Information.
next	Specifies the menu to go to next. Can be explicit or an array of possibilities dependent on ACS. See Flow Control in the ACS Checks section below. If next is not supplied, the next menu is this menus parent. Note that special built in methods such as @systemMethod:logoff can also be utilized here.
prompt	Specifies a prompt, by name, to use along with this menu. Prompts are configured in the prompts section. See Prompts for more information.
submit	Defines a submit handler when using prompt.
form	An object defining one or more forms available on this menu.
module	Sets the module name to use for this menu. The system ships with many build in modules or you can build your own!
config	An object containing additional configuration. See Config Block below.

Config Block

The config block for a menu entry can contain common members as well as a per-module (when module is used) settings.

Item	Description
cls	If true the screen will be cleared before showing this menu.
pause	If true a pause will occur after showing this menu. Useful for simple menus such as displaying art or status screens.
nextTimeout	Sets the number of milliseconds before the system will automatically advanced to the next menu.
baudRate	See baud rate information in General Art Information.
font	Sets a SyncTERM style font to use when displaying this menus art. See font listing in General Art Information.
menuFlags	An array of menu flag(s) controlling menu behavior. See Menu Flags below.

Menu Flags

The menuFlags field of a config block can change default behavior of a particular menu.

Flag	Description
noHistory	Prevents the menu from remaining in the menu stack / history. When this flag is set, when the next menu falls back, this menu will be skipped and the previous menu again displayed instead. Example: menuA -> menuB(noHistory) -> menuC: Exiting menuC returns the user to menuA.
popParent	When this menu is exited, fall back beyond the parent as well. Often used in combination with noHistory.
forwardArgs	If set, when the next menu is entered, forward any extraArgs arguments to this menu on to it.

Forms

ENiGMA½ uses a concept of forms in menus. A form is a collection of associated views. Consider a New User Application using the nua module: The default implementation utilizes a single form with multiple EditTextView views, a submit button, etc. Forms are identified by number starting with 0. A given menu may have mutiple forms (often associated with different states or screens within the menu).

Menus may also support more than one layout type by using a MCI key. A MCI key is a alpha-numerically sorted key made from 1:n MCI codes. This lets the system choose the appropriate set of form(s) based on theme or random art. An example of this may be a matrix menu: Perhaps one style of your matrix uses a vertical light bar (VM key) while another uses a horizontal (HM key). The system can discover the correct form to use by matching MCI codes found in the art to that of the available forms defined in menu.hjson.

For more information on views and associated MCI codes, see MCI Codes.

Submit Handlers

When a form is submitted, it's data is matched against a submit handler. When a match is found, it's action is performed.

Submit Actions

Submit actions are declared using the action member of a submit handler block. Actions can be kick off system/global or local-to-module methods, launch other menus, etc.

Action	Description
@menu:menuName	Takes the user to the menuName menu
@systemMethod:methodName	Executes the system/global method methodName. See System Methods below.
@method:methodName	Executes methodName local to the calling module. That is, the module set by the module member of a menu entry.
@method:/path/to/some_module.js:methodName	Executes methodName exported by the module at /path/to/some_module.js.

Advanced Action Handling

In addition to simple simple actions, action may also be:

• An array of objects containing ACS checks and a sub action if that ACS is matched. See Action Matches in the ACS documentation below for details.
• An array of actions. In this case a random selection will be made. Example:

submit: [
    {
        value: { command: "FOO" }
        action: [
            // one of the following actions will be matched:
            "@menu:menuStyle1"
            "@menu:menuStyle2"
        ]
    }
]

Method Signature

Methods executed using @method, or @systemMethod have the following signature:

(callingMenu, formData, extraArgs, callback)

System Methods

Many built in global/system methods exist. Below are a few. See system_menu_method for more information.

Method	Description
login	Performs a standard login.
login2FA_OTP	Performs a 2-Factor Authentication (2FA) One-Time Password (OTP) check, if configured for the user.
logoff	Performs a standard system logoff.
prevMenu	Goes to the previous menu.
nextMenu	Goes to the next menu (as set by next)
prevConf	Sets the users message conference to the previous available.
nextConf	Sets the users message conference to the next available.
prevArea	Sets the users message area to the previous available.
nextArea	Sets the users message area to the next available.

Example

Let's look a couple basic menu entries:

telnetConnected: {
    art: CONNECT
    next: matrix
    config: { nextTimeout: 1500 }
}

The above entry telnetConnected is set as the Telnet server's first menu entry (set by firstMenu in the Telnet server's config). The entry sets up a few things:

• A art spec of CONNECT. (See General Art Information).
• A next entry up the next menu, by name, in the stack (matrix) that we'll go to after telnetConnected.
• An config block containing a single nextTimeout field telling the system to proceed to the next (matrix) entry automatically after 1500ms.

Now let's look at matrix, the next entry from telnetConnected:

matrix: {
    art: MATRIX
    desc: Login Matrix
    form: {
        0: {
            //
            //  Here we have a MCI key of "VM". In this case we could
            //  omit this level since no other keys are present.
            //
            VM: {
                mci: {
                    VM1:  {
                        submit: true
                        focus:  true
                        items: [ "login", "apply", "log off" ]
                        argName: matrixSubmit
                    }
                }
                submit: {
                    *: [
                        {
                            value: { matrixSubmit: 0 }
                            action: @menu:login
                        }
                        {
                            value: { matrixSubmit: 1 },
                            action: @menu:newUserApplication
                        }
                        {
                            value: { matrixSubmit: 2 },
                            action: @menu:logoff
                        }
                    ]
                }
            }

            //
            //  If we wanted, we could declare a "HM" MCI key block here.
            //  This would allow a horizontal matrix style when the matrix art
            //  loaded contained a %HM code.
            //
        }
    }
}

In the above entry, you'll notice form. This defines a form(s) object. In this case, a single form by ID of 0. The system is then told to use a block only when the resulting art provides a VM (VerticalMenuView) MCI entry. Some other bits about the form:

• VM1 is then setup to submit and start focused via focus: true as well as have some menu entries ("login", "apply", ...) defined. We provide an argName of matrixSubmit for this element view.
• The submit object tells the system to attempt to apply provided match entries from any view ID (*).
• Upon submit, the first match will be executed. For example, if the user selects "login", the first entry with a value of { matrixSubmit: 0 } will match (due to 0 being the first index in the list and matrixSubmit being the arg name in question) causing action of @menu:login to be executed (go to login menu).

Prompts

Prompts are found in the prompts section of menu files. Prompts allow for quick user input and shorthand form requirements for menus. Additionally, prompts are often used for for multiple menus. Consider a pause prompt or menu command input for example.

TODO: additional prompt docs

ACS Checks

Menu modules can check user ACS in order to restrict areas and perform flow control. See ACS for available ACS syntax.

Menu Access

To restrict menu access add an acs key to config. Example:

opOnlyMenu: {
    desc: Ops Only!
    config: {
        acs: ID1
    }
}

Action Matches

Action blocks (action) can perform ACS checks:

// ...
{
    action: [
        {
            acs: SC1
            action: @menu:secureMenu
        }
        {
            action: @menu:nonSecureMenu
        }
    ]
}

Flow Control

The next member of a menu may be an array of objects containing an acs check as well as the destination. Depending on the current user's ACS, the system will pick the appropriate target. The last element in an array without an acs can be used as a catch all. Example:

login: {
    desc: Logging In
    next: [
        {
            //	>= 2 calls else you get the full login
            acs: NC2
            next: loginSequenceLoginFlavorSelect
        }
        {
            next: fullLoginSequenceLoginArt
        }
    ]
}

Art Asset Selection

Another area in which you can apply ACS in a menu is art asset specs.

someMenu: {
    desc: Neato Dorito
    art: [
        {
            acs: GM[couriers]
            art: COURIERINFO
        }
        {
            //  show ie: EVERYONEELSE.ANS to everyone else
            art: EVERYONEELSE
        }
    ]
}

Case Study: Adding a Sub Menu to Main

A very common task: You want to add a new menu accessible from "Main". First, let's create a new menu called "Snazzy Town"! Perhaps under the mainMenu entry somewhere, create a new menu:

snazzyTown: {
    desc: Snazzy Town
    art: snazzy
    config: {
        cls: true
        pause: true
    }
}

Now let's make it accessible by "S" from the main menu. By default the main menu entry is named mainMenu. Within the mainMenu's submit block you will see some existing action matches to "command". Simply add a new one pointing to snazzyTown:

{
    value: { command: "S" }
    action: @menu:snazzyTown
}

That's it! When users type "S" at the main menu, they'll be sent to the Snazzy Town menu. Since we did not supply additional flow logic when they exit, they will fall back to main.

Case Study: Adding a New User Password (NUP)

You've got a super 31337 board and want to prevent lamerz! Let's run through adding a NUP to your application flow.

Given the default menu system, two "pre" new user application menus exist due to the way Telnet vs SSH logins occur. We'll focus only on Telnet here. This menu is newUserApplicationPre. Let's say you want to display this preamble, but then ask for the NUP. If the user gets the password wrong, show them a LAMER.ANS and boot 'em.

First, let's create a new menu for the NUP:

newUserPassword: {
    art: NUP.ANS
    next: newUserApplication
    desc: NUP!

    form: {
        0: {
            mci: {
                ET1: {
                    // here we create an argument/variable of "nup"
                    argName: nup
                    focus: true
                    submit: true
                }
            }
            submit: {
                *: [
                    {
                        // if the user submits "nup" with the correct
                        // value of "nolamerz" action will send
                        // them to the next menu defined above --
                        // in our case: newUserApplication
                        value: { nup: "nolamerz" }
                        action: @systemMethod:nextMenu
                    }
                    {
                        // anything else will result in going to the badNewUserPassword menu
                        value: { nup: null }
                        action: @menu:badNewUserPassword
                    }
                ]
            }
        }
    }
}

Looks like we'll need a badNewUserPassword menu as well! Let's create a very basic menu to show art then disconnect the user.

badNewUserPassword: {
    art: LAMER.ANS
    // here we use a built in system method to boot them.
    next: @systemMethod:logoff
    config: {
        //  wait 2s after showing the art before kicking them
        nextTimeout: 2000
    }
}

Great, we have a couple new menus. Now let's just point to them. Remember the existing newUserApplicationPre menu? All that is left to do is point it's next to our newUserPassword menu:

newUserApplicationPre: {
    //  easy! Just tell the system where to go next
    next: newUserPassword
    // note that the rest of this menu is omitted for clarity
}