This guide will walk you through the manual migration steps to update your Hot Chocolate GraphQL server to version 14.

Start by installing the latest 14.x.x version of all of the HotChocolate.* packages referenced by your project.

This guide is still a work in progress with more updates to follow.

Breaking changes

Things that have been removed or had a change in behavior that may cause your code not to compile or lead to unexpected behavior at runtime if not addressed.

Banana Cake Pop and Barista renamed to Nitro

Dependency injection changes

• It is no longer necessary to use the [Service] attribute unless you're using keyed services, in which case the attribute is used to specify the key.

  • Hot Chocolate will identify services automatically.

• Support for the [FromServices] attribute has been removed.

  • As with the [Service] attribute above, this attribute is no longer necessary.

• Since the RegisterService method is no longer required, it has been removed, along with the ServiceKind enum.

• Scoped services injected into query resolvers are now resolver-scoped by default (not request scoped). For mutation resolvers, services are request-scoped by default.

• The default scope can be changed in two ways:

  1. Globally, using ModifyOptions:

     csharpCopy

     builder.Services
         .AddGraphQLServer()
         .ModifyOptions(o =>
         {
             o.DefaultQueryDependencyInjectionScope =
                 DependencyInjectionScope.Resolver;
             o.DefaultMutationDependencyInjectionScope =
                 DependencyInjectionScope.Request;
         });
     

  2. On a per-resolver basis, with the [UseRequestScope] or [UseResolverScope] attribute.

     • Note: The [UseServiceScope] attribute has been removed.

For more information, see the Dependency Injection documentation.

Entity framework integration changes

• The RegisterDbContext method is no longer required, and has therefore been removed, along with the DbContextKind enum.
• Use RegisterDbContextFactory to register a DbContext factory.

For more information, see the Entity Framework integration documentation.

New GID format

This release introduces a more performant GID serializer, which also simplifies the underlying format of globally unique IDs.

By default, the new serializer will be able to parse both the old and new ID format, while only emitting the new format.

This change is breaking if your consumers depend on the format of the GIDs, by for example parsing them (which they shouldn't). If possible, strive to decouple your consumers from the internal ID format and exposing the underlying ID as a separate field on your type if necessary.

If you don't want to switch to the new format yet, you can register the legacy serializer, which only supports parsing and emitting the old ID format:

builder.Services
    .AddGraphQLServer()
    .AddLegacyNodeIdSerializer()
    .AddGlobalObjectIdentification();

Note: AddLegacyNodeIdSerializer() needs to be called before AddGlobalObjectIdentification().

How to adopt incrementally in a distributed system

None of your services can start to emit the new ID format, as long as there are services that can't parse the new format.

Therefore, you'll first want to make sure that all of your services support parsing both the old and new format, while still emitting the old format.

This can be done, by configuring the new default serializer to not yet emit the new format:

builder.Services
    .AddGraphQLServer()
    .AddDefaultNodeIdSerializer(outputNewIdFormat: false)
    .AddGlobalObjectIdentification();

Note: AddDefaultNodeIdSerializer() needs to be called before AddGlobalObjectIdentification().

Once all of your services have been updated to this, you can start emitting the new format service-by-service, by removing the AddDefaultNodeIdSerializer() call and switching to the new default behavior:

builder.Services
    .AddGraphQLServer()
    .AddGlobalObjectIdentification();

IIdSerializer replaced by INodeIdSerializer

Previously, you could grab the IIdSerializer from your dependency injection container to manually parse and serialize globally unique identifiers (GID). As part of the changes to the GID format mentioned above, the IIdSerializer interface has been renamed to INodeIdSerializer.

The methods used for parsing and serialization have also been renamed:

The Parse() (previously Deserialize()) method has also changed its return type from IdValue to NodeId. The parsed Id value can now be accessed through the NodeId.InternalId instead of the IdValue.Value property.

The ability to encode the schema name in the GID via .Serialize("SchemaName", "MyType", "<raw-id>") has been dropped and is no longer supported.

Node Resolver validation

We now enforce that each object type implementing the Node interface also defines a resolver, so that the object can be refetched through the node(id: ID!) field.

You can opt out of this new behavior by setting the EnsureAllNodesCanBeResolved option to false.

builder.Services
    .AddGraphQLServer()
    .ModifyOptions(o => o.EnsureAllNodesCanBeResolved = false)

DataLoader.LoadAsync always returns nullable type

Previously, the LoadAsync method on a DataLoader was typed as non-nullable, even though null could be returned. This release changes the return type of LoadAsync to always be nullable.

Builder APIs

We have aligned all builder APIs to be more consistent and easier to use. Builders can now be created by using the static method Builder.New() and the Build() method to create the final object.

IQueryRequestBuilder replaced by OperationRequestBuilder

The interface IQueryRequestBuilder and its implementations were replaced with OperationRequestBuilder which now supports building standard GraphQL operation requests as well as variable batch requests.

The Build() method now returns a IOperationRequest which is implemented by OperationRequest and VariableBatchRequest.

We've also renamed and consolidated some methods on the OperationRequestBuilder:

IQueryResultBuilder replaced by OperationResultBuilder

The interface IQueryResultBuilder and its implementations were replaced with OperationResultBuilder which produces an OperationResult on Build().

IQueryResult replaced by IOperationResult

The interface IQueryResult was replaced with IOperationResult.

IExecutionResult.ExpectQueryResult replaced by .ExpectOperationResult

In your unit tests you might have been using result.ExpectQueryResult() to assert that a result is not a streamed response and rather a completed result. This assertion method has been renamed to ExpectOperationResult().

Operation complexity analyzer replaced

The Operation Complexity Analyzer in v13 has been replaced by Cost Analysis in v14, based on the draft IBM Cost Analysis specification.

• The Complexity property on RequestExecutorOptions (accessed via ModifyRequestOptions) has been removed.
• Cost analysis is enabled by default.

Please see the documentation for further information.

DateTime scalar enforces a specific format

The DateTime scalar will now enforce a specific format. The time and offset are now required, and fractional seconds are limited to 7. This aligns it with the DateTime Scalar spec (https://www.graphql-scalars.com/date-time/), with the one difference being that fractions of a second are optional, and 0-7 digits may be specified.

Please ensure that your clients are sending date/time strings in the correct format to avoid errors.

You can opt out of the format check with the following code:

builder.Services
    .AddGraphQLServer()
    .AddType(new DateTimeType(disableFormatCheck: true));

Persisted Queries renamed to Persisted Operations

Packages renamed

Interfaces renamed

Methods renamed

Options renamed

Defaults changed

MutationResult renamed to FieldResult

IReadStoredQueries and IWriteStoredQueries now IOperationDocumentStorage

IReadStoredQueries and IWriteStoredQueries have been merged into a single interface named IOperationDocumentStorage.

Renamed interface methods:

Required keyed services

Accessing a keyed service that has not been registered will now throw, instead of returning null. The return type is now non-nullable.

This change aligns the API with the regular (non-keyed) service access API.

Change to OnlyAllowPersistedOperations option

Before

ModifyRequestOptions(o => o.OnlyAllowPersistedOperations = true);

After

ModifyRequestOptions(o => o.PersistedOperations.OnlyAllowPersistedDocuments = true);

Connection getTotalCount constructor argument replaced with totalCount

Previously, you could supply an async method to the getTotalCount constructor argument when instantiating a Connection<T>. This method would only be evaluated to calculate the total count, if the totalCount field was selected on that Connection in a query.

return new Connection<MyType>(
    edges: [/* ... */],
    info: new ConnectionPageInfo(/* ... */),
    getTotalCount: async cancellationToken => 123)

In this release the constructor argument was renamed to totalCount and now only accepts an int for the total count, no longer a method to compute the total count. If you want to re-create the old behavior, you can use the new [IsSelected] attribute to conditionally compute the total count.

public Connection<MyType> GetMyTypes(
  [IsSelected("totalCount")] bool hasSelectedTotalCount,
  CancellationToken cancellationToken)
{
    var totalCount = 0;
    if (hasSelectedTotalCount)
    {
        totalCount = /* ... */;
    }

    return new Connection<MyType>(
        edges: [/* ... */],
        info: new ConnectionPageInfo(/* ... */),
        totalCount: totalCount)
}

Other changes

Change to SingleOrDefaultMiddleware

As a side-effect of fixing a bug in the SingleOrDefaultMiddleware, usage of this middleware along with EF Core may result in a warning being logged, as follows:

The query uses a row limiting operator ('Skip'/'Take') without an 'OrderBy' operator. This may lead to unpredictable results. If the 'Distinct' operator is used after 'OrderBy', then make sure to use the 'OrderBy' operator after 'Distinct' as the ordering would otherwise get erased.

We are looking at fixing this in a different way in the future (see #8070), but for now you can work around this by returning an IExecutable from your resolver by calling AsDbContextExecutable() on your IQueryable or DbSet, or by using Executable.From(...).

Deprecations

Things that will continue to function this release, but we encourage you to move away from.

SetPagingOptions

In an effort to align our configuration APIs, we're now also offering a delegate based configuration API for pagination options.

Before

builder.Services
    .AddGraphQLServer()
    .SetPagingOptions(new PagingOptions
    {
        MaxPageSize = 100,
        DefaultPageSize = 25
    });

After

builder.Services
    .AddGraphQLServer()
    .ModifyPagingOptions(opt =>
    {
        opt.MaxPageSize = 100;
        opt.DefaultPageSize = 25;
    });