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Object Definition

Object definition is a type present in multiple parts of meta-system. It is the standard we created for defining types of objects. This is declared in its own package at object-definition on NPM and Git Hub

The libraries contain both the typings and functions to validate both the definition and objects against a definition.

How to define​

This type expects to be an object which the properties are strings, and the values are type definitions, as the following example:

{
  "propertyName": { "type": "string" }
}

The available types are:

  • string
  • number
  • boolean
  • date
  • function
  • cloudedObject
  • enum - deep
  • object - deep
  • array - deep
  • any

CloudedObjects are objects that you don't know or don't want to specify its strucutre.

Shallow Types​

These are the types that does not require any other subType specification. They are: "string", "number", "boolean", "date", "function", "cloudedObject".

{
  "propertyName": { "type": <shallow-types> }
}

Deep Types​

There are other types that can have multiple levels, they are "object", "array", and "enum". These require a subtype to be considered valid, and they must be defined as the following:

// For "object"
{
  "deepProperty": {
    "type": "object",
    "subtype": {
      "someProperty": { "type": "string" }
    }
  }
}

// For "array"
{
  "listProperty": {
    "type": "array",
    "subtype": "string"
  }
}

// For "enum"
{
  "enumProperty": {
    "type": "enum",
    "subtype": ["possibleValue1", "value2", 3]
  }
}

When type === "object", subtype must be an Object Definition. When type === "array", subtype can be any of the shallow types, or another object definition. The object definition does not support array of arrays.

For type === "enum", the subtype must be an array of elements, which must be either strings, numbers, or a mix of both.

Required Fields​

You may also indicate whether a property is required or not, by using "required": true|false in the same level of the "type" property, as it goes:

{
  "name": { "type": "string", "required": true },
  "age": { "type": "number", "required": false },
  "nickname": { "type": "string" }
}

The absence of "required" is interpreted as "required": false.

Multiple Types​

On top of all said in page, you can type a prop with multiple types at the same time. This can be useful for a variable schema, in which a property can be both a string, or an array of strings, for instance.

For doing this, simply group types in an array:

{
  "foods": [{ "type": "string", "required": true }, { "type": "array", "subtype": "string", "required": true }],
  "age": { "type": "number", "required": false },
  "nickname": { "type": "string" }
}