Skip to main content

Queries

Executing your first Query​

With gqlxy-client, you can execute your queries in 2 ways:

C++20 Coroutine​

You can use coroutines to co_await on your request:

boost::asio::awaitable<void> run(Client& client) {
    auto result = co_await client.Query({
        .query = R"(
            query GetUser($id: ID!) {
                user(id: $id) {
                    id
                    name
                }
            }
        )",
        .variables = {{"id", "42"}}
    });

    if (result.errors) {
        for (const auto& e : *result.errors)
            std::cerr << e.message << "\n";
        co_return;
    }

    std::cout << result.data->dump(2) << "\n";
}

Client::Query() returns Observable<GraphQLResponse>. Awaiting it resolves the first (and only) value from the stream.

Subscribe style​

Observable<T> wraps an rpp::dynamic_observable<T>. You can call .subscribe() directly to get notified when the request succeeds or fails:

auto sub = client.Query({
    .query = "{ hello }"
}).subscribe(
    [](const GraphQLResponse& result) {
        std::cout << result.data->dump(2) << "\n";
    },
    [](std::exception_ptr e) {
        try { std::rethrow_exception(e); }
        catch (const std::exception& ex) { std::cerr << ex.what() << "\n"; }
    }
);

Caching​

By default, all the queries will be cached in the client's InMemoryCache unless you specify another FetchPolicy. See more on caching here.