App

Definition

Every Rinkhals app ships an app.json file next to its app.sh. This manifest describes the app to Rinkhals: its name, version and description, optional resource hints, and any settings that should be exposed in the Rinkhals touch UI.

At startup Rinkhals reads $version and only loads apps whose schema version it understands (currently 1). Apps with a missing or unsupported $version are skipped. The name, description, version and properties fields are also read by the touch UI to render the app's settings page.

JSON comments (//) are tolerated in app.json; Rinkhals strips them before parsing.

Schema

Field	Type	Required	Description
$version	string	Yes	Manifest schema version. Must be "1". Apps with any other value are skipped at startup.
name	string	Yes	Display name shown in the touch UI.
description	string	Yes	Short description shown in the touch UI.
version	string	Yes	The app's own version (free-form, e.g. "1.0" or a commit hash).
url	string	No	App or project URL.
requirements	object	No	Resource hints (see below). Informational only; not currently enforced by the loader.
properties	object	No	User-configurable settings shown in the touch UI (see below).

requirements

Field	Type	Description
cpu	number	Approximate CPU usage, in percent.
memory	number	Approximate memory usage, in MB.

properties

properties is an object whose keys are the property names used to store the value. Each value is an object describing how the property is presented and edited:

Field	Type	Description
display	string	Label shown in the UI. If omitted, the property is not shown.
type	string	One of text, number, enum, report, qr.
default	any	Default value used until the user sets one.
options	array	Valid choices, for enum types.
validation	string	Regex used to validate text input. Declared in the schema; not yet enforced by the touch UI.
range	array	[min, max] valid range for number input. Declared in the schema; not yet enforced by the touch UI.

Property type values:

• text - editable free text.
• number - editable numeric value.
• enum - a choice among options. As a special case, an enum whose options are exactly ["False", "True"] is rendered as a checkbox.
• report - a read-only value shown to the user (not editable).
• qr - a value shown to the user with a button to display it as a QR code.

Example

{
    "$version": "1", // Schema version

    "name": "Example app",
    "description": "Simple example app to showcase the app system",
    "version": "1.0",
    "url": "https://github.com/rinkhals-community/Rinkhals.Apps/tree/master/apps/example", // App or project URL

    "requirements":
    {
        "cpu": 0, // CPU usage in %
        "memory": 0 // Memory usage in MB
    },

    // Those properties will be exposed in Rinkhals UI
    "properties": {
        "text_input": {
            "display": "IP address", // Optional: if display is not set, the property won't be shown in the UI
            "type": "text", // Optional: property type for the UI (text, number, enum, report or qr)
            "validation": "^[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}$", // Optional: regex to validate strings
            "default": "0.0.0.0" // Optional: default value
        },
        "number_input": {
            "display": "Number",
            "type": "number",
            "range": [ 1024, 65536 ], // Optional: valid range for the number
            "default": 5678
        },
        "enum_input": {
            "display": "Option",
            "type": "enum",
            "options": [ "Choice 1", "Choice 2", "Choice 3" ] // Optional: valid choices for this enum
        },

        "text_output": {
            "display": "Status",
            "type": "report" // Reports will be shown to the user but not editable
        },
        "link_output": {
            "display": "Link",
            "type": "qr" // This property will be shown to the user with a QR code
        }
    }
}