in lib/config/decorators/entity-field.decorator.ts [12:25]
export function EntityField(fieldConfig?:FieldConfig):PropertyDecorator {
return function (entityPrototype: DataEntityType, propertyKey: string | symbol) {
fieldConfig = fieldConfig || {};
let propertyConstructor:Function = fieldConfig.type || (<any>Reflect).getMetadata("design:type", entityPrototype, propertyKey);
let field:Field = Object.assign({}, fieldConfig);
if (!field.id)
field.id = String(propertyKey);
field.type = fieldConfig.arrayOf || propertyConstructor;
field.isArray = propertyConstructor === Array;
entityFieldsService.addField(entityPrototype, field);
}
}