I thought that relay modern implemented a system whereby it would not try to fetch data until it was rendering the component that declared it. I am talking about fragment components. I have tried to test this but it is fetching all the data.
import React from "react";
import { Environment, Network, RecordSource, Store } from "relay-runtime";
import {
RelayEnvironmentProvider,
} from "react-relay/hooks";
import "./App.css";
import QueryLoaderComponent from "./QueryLoaderComponent";
import QueryComponent from "./QueryComponent";
async function fetchGraphQL(text: string, variables: Record<any, any>) {
// Fetch data from GitHub's GraphQL API:
const response = await fetch("https://countries.trevorblades.com/", {
method: "POST",
headers: {
"Content-Type": "application/json",
},
body: JSON.stringify({
query: text,
variables,
}),
});
// Get the response as JSON
return await response.json();
}
async function fetchRelay(params: any, variables: any) {
console.log(
`fetching query ${params.name} with ${JSON.stringify(variables)}`
);
return fetchGraphQL(params.text, variables);
}
// Export a singleton instance of Relay Environment configured with our network function:
const environment = new Environment({
network: Network.create(fetchRelay),
store: new Store(new RecordSource()),
});
function App() {
return (
<RelayEnvironmentProvider environment={environment}>
{/* <QueryLoaderComponent /> */}
<QueryComponent />
</RelayEnvironmentProvider>
);
}
export default App;
import { useState } from "react";
// @ts-ignore
import graphql from "babel-plugin-relay/macro";
import { QueryComponentQuery } from "./__generated__/QueryComponentQuery.graphql";
import { PreloadedQuery, useLazyLoadQuery, usePreloadedQuery } from "react-relay";
// import FragmentComponent from "./FragmentComponent";
const query = graphql`
query QueryComponentQuery($id: ID!) {
country(code: $id) {
name
...FragmentComponent_country
}
}
`;
interface Props {
// queryRef: PreloadedQuery<QueryComponentQuery>;
}
const QueryComponent = ({
// queryRef
}: Props) => {
const data = useLazyLoadQuery<QueryComponentQuery>(query, { id: "US"});
const [showContinent, setShowContinent] = useState(false);
return (
<div>
<button onClick={() => setShowContinent(!showContinent)}>
{showContinent ? "Hide" : "Show"} continent
</button>
<h1>{data.country?.name}</h1>
{/* <ul>
{data.countries.map((country: any) => (
<li key={country.name}>
{country.name}{" "}
{showContinent && <FragmentComponent country={country} />}
</li>
))}
</ul> */}
</div>
);
};
export default QueryComponent;
import { useFragment } from "react-relay";
// @ts-ignore
import graphql from "babel-plugin-relay/macro";
import { FragmentComponent_country$key } from "./__generated__/FragmentComponent_country.graphql";
export const fragment = graphql`
fragment FragmentComponent_country on Country {
continent {
name
}
}
`;
interface Props {
country: FragmentComponent_country$key;
}
const FragmentComponent = ({ country }: Props) => {
const data = useFragment(fragment, country);
return <div>{data.continent.name}</div>;
};
export default FragmentComponent;
this is fetching the data for the fragment component even though it is not rendering the fragment component. is there a way to defer it until it is rendering the component?
