Upgrading to GraphQL 4#

The 4.0 release of silverstripe/graphql underwent a massive set of changes representing an entire rewrite of the module. This was done as part of a year-long plan to improve performance. While there is no specific upgrade path, there are some key things to look out for and general guidelines on how to adapt your code from the 3.x release to 4.x.

Note that this document is aimed towards developers who have a custom GraphQL schema. If you are updating from GraphQL 3 to 4 but do not have a custom schema, you should familiarise yourself with the building the schema documentation, but you do not need to read this document.

In this section, we'll cover each of these upgrade issues in order of impact.

GraphQL schemas require a build step#

The most critical change moving from 3.x to 4.x affects the developer experience. The key to improving performance in GraphQL requests was eliminating the overhead of generating the schema at runtime. This didn't scale. As the GraphQL schema grew, API response latency increased.

To eliminate this overhead, the GraphQL API relies on generated code for the schema. You need to run a task to build it.

vendor/bin/sake dev/graphql/build schema=default

Check the building the schema documentation to learn about the different ways to build your schema.

The Manager class, the godfather of GraphQL 3, is gone#

silverstripe/graphql 3.x relied heavily on the Manager class. This became a catch-all that handled scaffolding, registration of types, running queries and middleware, error handling, and more. This class has been broken up into two separate concerns:

• Schema <- register your stuff here
• QueryHandlerInterface <- Handles GraphQL queries, applies middlewares and context. You'll probably never have to touch it.

Upgrading#

Before#

SilverStripe\GraphQL\Manager:
  schemas:
    default:
      types: {}
      queries: {}
      mutations: {}

After#

SilverStripe\GraphQL\Schema\Schema:
  schemas:
    default:
      src:
        - app/_graphql # A directory of your choice

Add the appropriate YAML files to the directory. For more information on this pattern, see the configuring your schema section.

app/_graphql
  types.yml
  queries.yml
  mutations.yml
  models.yml
  enums.yml
  interfaces.yml
  unions.yml

TypeCreator, QueryCreator, and MutationCreator are gone#

A thorough look at how these classes were being used revealed that they were really just functioning as value objects that effectively created configuration in a static context. That is, they had no real reason to be instance-based. Most of the time, they can easily be ported to configuration.

Upgrading#

Before#

namespace App\GraphQL;

class GroupTypeCreator extends TypeCreator
{
    public function attributes()
    {
        return [
            'name' => 'group',
        ];
    }

    public function fields()
    {
        return [
            'ID' => ['type' => Type::nonNull(Type::id())],
            'Title' => ['type' => Type::string()],
            'Description' => ['type' => Type::string()],
        ];
    }
}

After#

# app/_graphql/types.yml
group:
  fields:
    ID: ID!
    Title: String
    Description: String

That's a simple type, and obviously there's a lot more to it than that. Have a look at the working with generic types section of the documentation to learn more.

Resolvers must be static callables#

You can no longer use instance methods for resolvers. They can't be easily transformed into generated PHP code in the schema build step. These resolvers should be refactored to use the static declaration and moved into a class.

Upgrading#

Move your resolvers into one or many classes, and register them. Notice that the name of the method determines what is being resolved, where previously that would be the name of a resolver class. Now, multiple resolver methods can exist within a single resolver class.

Before#

namespace App\GraphQL;

class LatestPostResolver implements OperationResolver
{
    public function resolve($object, array $args, $context, ResolveInfo $info)
    {
        return Post::get()->sort('Date', 'DESC')->first();
    }
}

After#

# app/_graphql/config.yml
resolvers:
  - App\GraphQL\MyResolverClassA
  - App\GraphQL\MyResolverClassB

namespace App\GraphQL;

class MyResolverClassA
{
    public static function resolveLatestPost($object, array $args, $context, ResolveInfo $info)
    {
        return Post::get()->sort('Date', 'DESC')->first();
    }
}

This method relies on resolver discovery, which you can learn more about in the documentation.

Alternatively, you can hardcode the resolver into your config. Note that the resolver value here is a YAML array, which PHP will interpret as a callable.

# app/_graphql/queries.yml
latestPost:
  type: Post
  resolver: ['App\GraphQL\MyResolvers', 'resolveLatestPost']

ScaffoldingProviders are now SchemaUpdaters#

The ScaffoldingProvider interface has been replaced with SchemaUpdater. If you were updating your schema with procedural code, you'll need to implement SchemaUpdater and implement the updateSchema() method.

Upgrading#

Register your schema builder, and change the code.

Before#

SilverStripe\GraphQL\Manager:
  schemas:
    default:
      scaffolding_providers:
        - 'App\GraphQL\MyProvider'

namespace App\GraphQL;

class MyProvider implements ScaffoldingProvider
{
    public function provideGraphQLScaffolding(SchemaScaffolder $scaffolder)
    {
        // updates here...
    }
}

After#

SilverStripe\GraphQL\Schema\Schema:
  schemas:
    default:
      execute:
        - 'App\GraphQL\MyProvider'

namespace App\GraphQL;

class MyProvider implements SchemaUpdater
{
    public function updateSchema(Schema $schema): void
    {
        // updates here...
    }
}

Goodbye scaffolding, hello models#

In silverstripe/graphql 3.x, a massive footprint of the codebase was dedicated to a DataObject-specific API called "scaffolding" that was used to generate types, queries, fields, and more from the ORM. In 4.x, that approach has been replaced with a concept called model types.

A model type is just a type that is backed by a class that has awareness of its schema (like a DataObject!). At a high-level, it needs to answer questions like:

• Do you have field X?
• What type is field Y?
• What are all the fields you offer?
• What operations do you provide?
• Do you require any extra types to be added to the schema?

Upgrading#

The 4.x release ships with a model type implementation specifically for DataObjects, which you can use a lot like the old scaffolding API. It's largely the same syntax, but a lot easier to read.

Before#

SilverStripe\GraphQL\Manager:
  schemas:
    default:
      scaffolding:
        types:
          SilverStripe\Security\Member:
            fields: '*'
            operations: '*'
          SilverStripe\CMS\Model\SiteTree:
            fields:
              title: true
              content: true
            operations:
              read: true

After#

# app/_graphql/models.yml
SilverStripe\Security\Member:
  fields: '*'
  operations: '*'

SilverStripe\CMS\Model\SiteTree:
  fields:
    title: true
    content: true
  operations:
    read: true

DataObject GraphQL field names are lowerCamelCase by default#

The 3.x release of the module embraced an anti-pattern of using UpperCamelCase field names so that they could map directly to the conventions of the ORM. This makes frontend code look awkward, and there's no great reason for the Silverstripe CMS GraphQL server to break convention. In this major release, the lowerCamelCase approach is encouraged.

Upgrading#

Change the casing in your queries.

Before#

query readPages {
  edges {
    nodes {
     Title
     ShowInMenus
    }
  }
}

After#

query readPages {
  edges {
    node {
      title
      showInMenus
    }
  }
}

edges no longer required#

We don't have cursor-based pagination in Silverstripe CMS, so the use of edges is merely for convention. You can eliminate a layer here and just use nodes, but edges still exists for backward compatibility.

query readPages {
  nodes {
    title
    showInMenus
  }
}

DataObject type names are simpler#

To avoid naming collisions, the 3.x release of the module used a pretty aggressive approach to ensuring uniqueness when converting a DataObject class name to a GraphQL type name, which was <vendorName><shortName>.

In the 4.x release, the typename is just the shortName by default, which is based on the assumption that most of what you'll be exposing is in your own app code, so collisions aren't that likely.

Upgrading#

Change any references to DataObject type names in your queries

Before#

query SilverStripeSiteTrees {}

After#

query SiteTrees {}

The Connection class has been replaced with plugins#

In the 3.x release, you could wrap a query in the Connection class to add pagination features. In 4.x, these features are provided via the new plugin system.

The good news is that all DataObject queries are paginated by default, and you shouldn't have to worry about this. But if you are writing a custom query and want it paginated, check out the section on adding pagination to a custom query.

Additionally, the sorting features that were provided by Connection have been moved to a plugin dedicated to SS_List results. Again, this plugin is applied to all DataObject classes by default, and will include all of their sortable fields by default - though this is configurable. See the query plugins section for more information.

Upgrading#

There isn't much you have to do here to maintain compatibility. If you prefer to have a lot of control over what your sort fields are, check out the linked documentation above.

Query filtering has been replaced with a plugin#

The previous QueryFilter API has been vastly simplified in a new plugin. Filtering is provided to all read queries by default, and should include all filterable fields including nested relationships - though this is configurable. See the query plugins section for more information.

Upgrading#

There isn't much you have to do here to maintain compatibility. If you prefer to have a lot of control over what your filter fields are, check out the linked documentation above.

Query permissions have been replaced with a plugin#

This was mostly an internal API, and shouldn't be affected in an upgrade - but if you want more information on how it works you can read the permissions documentation.

Enums are first-class citizens#

In the 3.x release, there was no clear path to creating enum types, but in 4.x, they have a prime spot in the configuration layer.

Before#

(A type creator that has been hacked to return an Enum singleton?)

After#

# app/_graphql/enums.yml
Status:
  values:
    SHIPPED: Shipped
    CANCELLED: Cancelled
    PENDING: Pending

See the Enums, unions, and interfaces documentation for more information.