Object Type

Object Types represent the probably most used primitive types in GraphQL applications. The hold a set of fields, where each field has it’s own type, which lays the foundation for building complex hierachies and systems.

In php-graphql object types are an instance of the GraphQLObjectType class, which are configured via the constructor.

/*
 * HINT: this code section is an excerpt of the books example in the 'examples/' folder
 *       and is not ment to work solely.
 */
$bookType = new GraphQLObjectType("Book", "The Book Type", function () use (&$authorType, &$bookCategoryType, &$authors, &$bookType, &$books) {
    return [
        new GraphQLTypeField(
            "id",
            new GraphQLNonNull(new GraphQLInt()),
            "ID of the Book"
        ),
        new GraphQLTypeField(
            "name",
            new GraphQLString(),
            "Name of the Book",
            function ($parent, $args, $context) {
                return ($args["prefix"] ?? "") . $parent["name"] . ($context["addOn"] ?? "");
            },
            [
                new GraphQLTypeFieldArgument("prefix", new GraphQLString())
            ]
        ),
        new GraphQLTypeField(
            "author",
            new GraphQLNonNull($authorType),
            "Author of the book",
            function ($parent, $args) use ($authors) {
                $index = array_search($parent["authorId"], array_column($authors, 'id'));
                return $authors[$index];
            }
        )
    ];
});

GraphQLObjectType Constructor

Parameters used for the GraphQLObjectType constructors are (in the following order):

Parameter	Type	Description	Required
type	`string`	Name of the new type. Used for introspection.	☑️
description	`string`	Description of the new type. Used for introspection.	☑️
fields	`\Closure`	Function that returns an array of `GraphQLTypeField`. Is called as soon the fields are needed. Used during validation and execution.	☑️
interfaces	`array`	Array of `GraphQLInterface` that should be implemented.
isTypeOfFn	`\Closure`	Function that returns wether an object or array is type of this object or not. Used during execution. If not passed, uses default resolver.

GraphQLTypeField Constructor

A GraphQLTypeField is a field that can only be used in a field set e.g. in a GraphQLObjectType. Parameters used for the GraphQLTypeField constructors are (in the following order):

Parameter	Type	Description	Required
id	`string`	Name of the new field. Used for introspection, validation and execution.	☑️
type	`GraphQLType`	The type of the new field.	☑️
description	`string`	Description of the new field. Used for introspection.	☑️
resolve	`\Closure`	Function whose signature looks like this `function($parent, $args, $context, $info) {...}`. It should resolve the field’s actual content based on the parameters. If not passed, uses default resolver.	️
args	`array`	Array of `GraphQLFieldArgument` that represent possible input arguments.
defaultValue	`mixed`	The field’s default value (deprected).
deprecationReason	`string`	If passed, the field is marked internally as deprected and the argument is stored as explanation.