index.md

Type System

Types

Types can be define 3 different ways:

1. The configuration way

   Creating this file extension .types.yml or .types.xml in src/*Bundle/Resources/config/graphql or app/config/graphql. See the different possible types:

   • Scalars
   • Object
   • Interface
   • Union
   • Enum
   • Input Object
   • Lists
   • Non-Null

   You can also define custom dirs using config:

   overblog_graphql:
       definitions:
           mappings:
               # auto_discover: false # to disable bundles and root dir auto discover
               types:
                   -
                       type: yaml # or xml or graphql null
                       dir: "%kernel.root_dir%/.../mapping" # sub directories are also searched
                       # suffix: .types # use to change default file suffix
                   -
                       types: [yaml, graphql] # to include different types from the same dir
                       dir: "%kernel.root_dir%/.../mapping"

2. The PHP way

   You can also declare PHP types (any subclass of GraphQL\Type\Definition\Type) in src/*Bundle/GraphQL or app/GraphQL they will be auto discover (thanks to auto mapping). Auto map classes are accessible by service id (example: AppBunble\GraphQL\Type\DateTimeType), you can also alias a type by implementing Overblog\GraphQLBundle\Definition\Resolver\AliasedInterface that returns an array of aliases.

   here an example:

   <?php
   
   namespace App\GraphQL\Type;
   
   use Overblog\GraphQLBundle\Definition\Resolver\AliasedInterface;
   use GraphQL\Type\Definition\ScalarType;
   
   class DateTimeType extends ScalarType implements AliasedInterface
   {
       /**
        * {@inheritdoc}
        */
       public static function getAliases()
       {
           return ['DateTime', 'Date'];
       }
       // ...
   }

   You can also define custom dirs using config:

   overblog_graphql:
       definitions:
           auto_mapping:
               directories:
                   - "%kernel.root_dir%/src/*Bundle/CustomDir"
                   - "%kernel.root_dir%/src/AppBundle/{foo,bar}"

   If using Symfony 3.3+ disabling auto mapping can be a solution to leave place to native DI autoconfigure:

   overblog_graphql:
       definitions:
           auto_mapping: false

   Here an example of how this can be done with DI autoconfigure:

   services:
       _instanceof:
           GraphQL\Type\Definition\Type:
               tags: ['overblog_graphql.type']
   
       App\Type\:
           resource: '../src/Type'

   Note:

   • Types are lazy loaded so when using Symfony DI autoconfigure or this bundle auto mapping, the only access to type is FQCN (or aliases if implements the aliases interface).
   • When using service id as FQCN in yaml definition, backslashes must be correctly escaped,

3. The service way

   Creating a service tagged overblog_graphql.type

   services:
       AppBundle\GraphQL\Type\DateTime:
           # only for sf < 3.3
           #class: AppBundle\GraphQL\Type\DateTime
           tags:
               - { name: overblog_graphql.type, alias: DateTime }