React Form Builder | createEntity

This function creates an entity definition that can be subsequently referenced in multiple builders.

By an entity definition, we simply mean an object with specific properties. The function itself serves primarily as a type safety helper and doesn't perform any underlying logic.

Reference

`createEntity(options)`

Use the createEntity function to create an entity definition.

import { createEntity } from "@coltorapps/builder";

import { labelAttribute } from "./label-attribute";

export const textFieldEntity = createEntity({
  name: "textField",
  attributes: [labelAttribute],
  validate(value) {
    if (typeof value !== "string") {
      throw new Error("Must be a string");
    }

    return value;
  },
});

Parameters

createEntity accepts a single parameter, which should be an object containing the following properties:

Property	Type	Description
`name`	string	The entity's name, which appears as the `type` property on entities instances within the schema.
`attributes`	array optional	An optional array of attributes definitions. Defaults to `[]`.
`validate`	function optional	An optional validation function for checking entity values during schema validation. It can be asynchronous, and any exceptions it raises will be automatically caught and stored in the builder store, or returned back to you when validating the schema inline. The method receives two arguments: the entity's value and the context object. Not defining this method implies that the entity cannot have a value. Defaults to `() => undefined`.
`childrenAllowed`	boolean optional	An optional flag for determining whether the entity can or cannot have any child entities. Defaults to `false`.
`parentRequired`	boolean optional	An optional flag for indicating whether the entity must always have a parent entity. Defaults to `false`.
`defaultValue`	function optional	An optional function for populating the entity's value with a default during the interpreter store initialization. It receives the context object as an argument. The return type of this method must match the return type of the `validate` method, but it can also return `undefined`. This method has no effect when the `validate` method is not defined. Defaults to `() => undefined`.
`shouldBeProcessed`	function optional	An optional function that should return either `true` or `false`, indicating whether both the entity and all its child entities should be displayed and validated or not. It receives the context object as an argument. Defaults to `() => true`.
`attributesExtensions`	object optional	An optional object for extending or overriding attribute validations. Defaults to {}. See below for structure details.

Returns

The createEntity function essentially forwards the provided options parameter as the returned object and doesn't perform any underlying logic, with optional parameters falling back to the defaults described above when not provided.

Property	Type	Description
`name`	string	The entity's name.
`attributes`	array	An array of attributes definitions.
`validate`	function	A validation function for checking entity values during schema validation.
`childrenAllowed`	boolean	A flag which determines whether the entity can or cannot have any child entities.
`parentRequired`	boolean	A flag which determines whether the entity must always have a parent entity.
`defaultValue`	function	A function for populating the entity's value with a default during the interpreter store initialization.
`shouldBeProcessed`	function	A function that determines whether both the entity and all its child entities should be displayed and validated or not.
`attributesExtensions`	object	An object for extending or overriding attribute validations.
`valueAllowed`	boolean	A flag that indicates whether the entity is allowed to have values. It is set to `true` only when the `validate` method was provided when creating the entity definition.

Usually, you will not need to manually access these properties; instead, the created entity definition object is typically passed directly to a builder definition.

Context

The context object is passed as an argument to the validate, defaultValue, and shouldBeProcessed methods within the createEntity function. It includes the following properties:

Property	Type	Description
`entity`	object	The entity instance.
`entitiesValues`	object	The values of all entities during schema interpretation.

Attributes Extensions

Extending or overriding attribute validations can be achieved using the attributesExtensions property when creating an entity definition, which is a deeply partial object of the following shape:

{
  // The key corresponds to the name of an attribute.
  attributeName?: {
    // The logic for validating the attribute's value.
    validate?: (value, context) => TValue
  }
}

The validate method in an attribute's extension receives the same arguments as the base validate method of the attribute, except the context object also includes an additional context.validate(value) method, tessentially represents the base validation of the attribute. Invoking it is optional, allowing you to entirely replace the validation with custom logic.

The return type of the new validation must match the return type of the attribute's base validate method.