DgsGraphQlClient support for GraphQLMultiQueryRequest

[giridhargg]

Clients should be able to send multiple queries(netflix dgs generated query and projection DTO's) using the DgsGraphQlClient wrapper class? For example, I have below schema:

type Query {
    books: [Book]
    authors: [Author]
}

type Book {
    id: ID
    name: String!
    authors: [Author!]!
}
type Author {
    name: String!
}

The generated DTO's for queries and projections, and the multi-query request will be:

var booksGraphqlQuery = BooksGraphQLQuery.newRequest().build();
var authorsGraphqlQuery = AuthorsGraphQLQuery.newRequest().build();
var booksProjection = BooksProjectionRoot<>().id().name().authors().name();
var authorsProjection = AuthorsProjectionRoot<>().name();

var booksRequest = new GraphQLQueryRequest(booksGraphqlQuery, booksProjection);
var authorsRequest = new GraphQLQueryRequest(authorsGraphqlQuery, authorsProjection);

var multiQueryRequest = new GraphQLMultiQueryRequest(List.of(booksRequest, authorsRequest));

Now I need to send this multi-query request using DgsGraphQlClient for example something like:

var dgsGraphQlClient = DgsGraphQlClient.create(HttpGraphQlClient.builder(webClientBuilder).build());
var response = dgsGraphQlClient.request(multiQueryRequest).executeSync();

But I see it's not supported with it yet. I know there is a work around, using the following code:

var response = dgsGraphQlClient.getGraphQlClient().document(multiQueryRequest.serialize()).executeSync();

But, I am hoping DgsGraphQlClient to do all of the above things, where I will just pass in the DTO's of queries and projections directly as arguments to it.

[rstoyanchev]

One option would be to add a new request(GraphQLQuery query) method on DgsGraphQlClient.Builder as a way of adding an additional request. Each time this method is called we would create a GraphQLQueryRequest from the current values of query, projectionNode, and coercingMap fields and reset them to prepare for the next query.