public async Task <IPreProcessedCursorSlice <ICharacter> > GetCharactersPaginatedAsync(
[Service] ICharacterRepository repository,
//THIS is now injected by Pre-Processed extensions middleware...
[GraphQLParams] IParamsContext graphQLParams
)
{
var repoDbParams = new GraphQLRepoDbMapper <CharacterDbModel>(graphQLParams);
//********************************************************************************
//Get the data from the database via our lower level data access repository class.
//NOTE: Selections (e.g. Projections), SortFields, PagingArgs are all pushed
// down to the Repository (and underlying Database) layer.
var charactersSlice = await repository.GetCursorPagedCharactersAsync(
repoDbParams.GetSelectFields(),
repoDbParams.GetSortOrderFields(),
repoDbParams.GetCursorPagingParameters()
);
//With a valid Page/Slice we can return a PreProcessed Cursor Result so that
// it will not have additional post-processing in the HotChocolate pipeline!
//NOTE: Filtering can be applied but ONLY to the results we are now returning;
// Because this would normally be pushed down to the Sql Database layer.
return(charactersSlice.AsPreProcessedCursorSlice());
//********************************************************************************
}
public async Task <PreProcessedCursorSlice <Droid> > GetDroidsPaginatedAsync(
[Service] ICharacterRepository repository,
//THIS is now injected by Pre-Processed extensions middleware...
[GraphQLParams] IParamsContext graphQLParams
)
{
var repoDbParams = new GraphQLRepoDbMapper <CharacterDbModel>(graphQLParams);
//********************************************************************************
//Get the data and convert to List() to ensure it's an Enumerable
// and no longer using IQueryable to successfully simulate
// pre-processed results.
//NOTE: Selections (e.g. Projections), SortFields, PagingArgs are all pushed
// down to the Repository (and underlying Database) layer.
var charactersSlice = await repository.GetPagedDroidCharactersAsync(
repoDbParams.GetSelectFields(),
repoDbParams.GetSortOrderFields() ?? OrderField.Parse(new { Name = Order.Ascending }),
repoDbParams.GetCursorPagingParameters()
);
//With a valid Page/Slice we can return a PreProcessed Cursor Result so that
// it will not have additional post-processing in the HotChocolate pipeline!
//NOTE: Filtering can be applied but ONLY to the results we are now returning;
// Because this would normally be pushed down to the Sql Database layer.
return(charactersSlice.AsPreProcessedCursorSlice());
//********************************************************************************
}
public override void OnConfigure(
IDescriptorContext context,
IObjectFieldDescriptor descriptor,
MemberInfo member)
{
descriptor.Resolve(async ctx =>
{
ICharacter character = ctx.Parent <ICharacter>();
ICharacterRepository repository = ctx.Service <ICharacterRepository>();
//This is injected by the PreProcessing middleware wen enabled...
var graphQLParams = new GraphQLParamsContext(ctx);
//********************************************************************************
//Perform some pre-processed retrieval of data from the Repository...
//Notice Pagination processing is pushed down to the Repository layer also!
//Get RepoDb specific mapper for the GraphQL parameter context...
//Note: It's important that we map to the DB Model (not the GraphQL model).
var repoDbParams = new GraphQLRepoDbMapper <CharacterDbModel>(graphQLParams);
//Now we can retrieve the related and paginated data from the Repo...
var pagedFriends = await repository.GetCharacterFriendsAsync(character.Id, repoDbParams.GetCursorPagingParameters());
return(new PreProcessedCursorSlice <ICharacter>(pagedFriends));
//********************************************************************************
});
}