Project Moved
As of March 7, 2020, next-urql has been moved into a core package in the urql monorepo. In an effort to better consolidate and centralize work on the extended urql ecosystem, we at Formidable feels it makes sense to group these projects under a single umbrella. This also promotes better discoverability for contributors and future maintainers.
All new issues, pull requests, and code discussion for this project should happen there. All new releases will be published from that package. Thanks so much for using next-urql!
next-urql
A set of convenience utilities for using urql with NextJS.
Motivation
Using GraphQL with server-side rendering in React is a challenging problem. Currently, React has no support for Suspense for data fetching on the server. To get around this, a prepass step can be used to walk the tree (or a subsection of the tree) of your React application and suspend when it encounters thrown Promises. For more information, check out react-ssr-prepass.
next-urql handles integrating this prepass step for you, such that your NextJS application using urql will prefetch your GraphQL queries on the server before sending down markup to the Client.
Installation
Install next-urql along with its peerDependencies.
npm install --save next-urql urql react-is isomorphic-unfetchreact-is, styled-components, and isomorphic-unfetch help to support server-side Suspense with react-ssr-prepass. This assumes you have followed the basic installation steps for urql here.
Usage
To use next-urql, first import the withUrqlClient higher order component.
import { withUrqlClient } from 'next-urql';Then, for any page in your pages directory for which you want to prefetch GraphQL queries, wrap the page in withUrqlClient. For example, let's say you have an index.js page that renders two components that make GraphQL requests using urql, PokemonList and PokemonTypes. To run their queries initially on the server-side you'd do something like the following:
import React from 'react';
import Head from 'next/head';
import { withUrqlClient } from 'next-urql';
import PokemonList from '../components/pokemon_list';
import PokemonTypes from '../components/pokemon_types';
const Root = () => (
<div>
<Head>
<title>Root</title>
<link rel="icon" href="/static/favicon.ico" />
</Head>
<PokemonList />
<PokemonTypes />
</div>
);
export default withUrqlClient({ url: 'https://graphql-pokemon.now.sh' })(Root);Read more below in the API section to learn more about the arguments that can be passed to withUrqlClient.
Integration with _app.js
Next allows you to override the root of your application using a special page called _app.js. If you want to have all GraphQL requests in your application fetched on the server-side, you could wrap the component exported by _app.js in withUrqlClient. However, be aware that this will opt you out of automatic static optimization for your entire application. In general, it's recommended practice to only use withUrqlClient on the pages that have GraphQL operations in their component tree. Read more in the Caveats section. Check out our example for using next-urql with _app.js here.
API
next-urql exposes a single higher order component, withUrqlClient. This HoC accepts two arguments:
clientOptions (Required)
The clientOptions argument is required. It represents all of the options you want to enable on your urql Client instance. It has the following union type:
type NextUrqlClientConfig =
| Omit<ClientOptions, 'exchanges' | 'suspense'>
| ((ctx: NextPageContext) => Omit<ClientOptions, 'exchanges' | 'suspense'>);The ClientOptions interface comes from urql itself and has the following type:
interface ClientOptions {
/** The GraphQL endpoint your application is using. */
url: string;
/** Any additional options to pass to fetch. */
fetchOptions?: RequestInit | (() => RequestInit);
/** An alternative fetch implementation. */
fetch?: typeof fetch;
/** The exchanges used by the Client. See mergeExchanges below for information on modifying exchanges in next-urql. */
exchanges?: Exchange[];
/** A flag to enable suspense on the server. next-urql handles this for you. */
suspense?: boolean;
/** The default request policy for requests. */
requestPolicy?: RequestPolicy;
/** Use HTTP GET for queries. */
preferGetMethod?: boolean;
/** Mask __typename from results. */
maskTypename?: boolean;
}This means you have two options for creating your urql Client. The first involves just passing the options as an object directly:
withUrqlClient({
url: 'http://localhost:3000',
fetchOptions: {
referrer: 'no-referrer',
redirect: 'follow',
},
});The second involves passing a function, which receives Next's context object, ctx, as an argument and returns urql's Client options. This is helpful if you need to access some part of Next's context to instantiate your Client options. Note: ctx is only available on the initial server-side render and not on client-side navigation. This is necessary to allow for different Client configurations between server and client.
withUrqlClient(ctx => ({
url: 'http://localhost:3000',
fetchOptions: {
headers: {
Authorization: ctx
? `Bearer ${ctx?.req?.headers?.Authorization ?? ''}`
: localStorage.getItem('token') ?? '',
},
},
}));In client-side SPAs using urql, you typically configure the Client yourself and pass it as the value prop to urql's context Provider. withUrqlClient handles setting all of this up for you under the hood. By default, you'll be opted into server-side Suspense and have the necessary exchanges set up for you, including the ssrExchange. If you need to customize your exchanges beyond the defaults next-urql provides, use the second argument to withUrqlClient, mergeExchanges.
mergeExchanges (Optional)
The mergeExchanges argument is optional. This is a function that takes the ssrExchange created by next-urql as its only argument and allows you to configure your exchanges as you wish. It has the following type signature:
(ssrExchange: SSRExchange) => Exchange[]By default, next-urql will incorprate the ssrExchange into your exchanges array in the correct location (after any other caching exchanges, but before the fetchExchange – read more here). Use this argument if you want to configure your Client with additional custom exchanges, or access the ssrCache directly to extract or restore data from its cache.
Different Client configurations on the client and the server
There are use cases where you may need different configurations for your urql Client on the client-side and the server-side; for example, you may want to interact with one GraphQL endpoint on the server-side and another on the client-side. next-urql supports this as of v0.3.0. We recommend using typeof window === 'undefined' or a process.browser check.
withUrqlClient({
url:
typeof window === 'undefined'
? 'https://my-server-graphql-api.com/graphql'
: 'https://my-client-graphql-api.com/graphql',
});If you want more customization of your Client instance to modify requests on specific routes, for instance, consider using a custom exchange. You can find an example of that here.
Accessing the urql Client inside a Page component's getInitialProps method
There are use cases where you may want to access the urql Client instance inside your Page component's getInitialProps method. To support this, we actually attach the urql Client instance to the ctx object passed to your Page's getInitialProps method. You can access it like so:
import { NextUrqlPageContext } from 'next-urql';
const Page = () => {
return <main />;
};
Page.getInitialProps = async (ctx: NextUrqlPageContext) => {
// Do something with the urql Client instance!
let client = ctx.urqlClient;
return {
...props,
};
};Usage with ReasonML
While there are no official bindings for using next-urql with ReasonML, porting next-urql to Reason is not too difficult. Moreover, having your own bindings means you can select only the pieces you need from the library. Here's an example of how you could bind next-urql if you only needed access to the non-functional clientOptions API, and only wanted to pass a url and fetchOptions. This assumes BuckleScript 7 to take advantage of records compiling into plain JS objects and assumes usage of bs-fetch.
type clientOptions = {
url: string,
fetchOptions: Fetch.requestInit
};
[@bs.module "next-urql"]
external withUrqlClient:
(. clientOptions) =>
(. React.component('props)) => React.component('props) =
"withUrqlClient";Which can then be used like so:
let headers = Fetch.HeadersInit.make({ "Content-Type": "application/json" });
let client = {
url: "https://mygraphqlapi.com/graphql",
fetchOptions: Fetch.RequestInit.make(~headers, ~method_=POST, ())
};
[@react.component]
let make = () => {
<h1>"Heck yeah, next-urql with Reason!"->React.string</h1>
};
let default = (withUrqlClient(. clientOptions))(. make);The great part about writing thin bindings like this is that they are zero cost – in fact, the above bindings get totally compiled away by BuckleScript, so you get the full benefits of type safety with absolutely zero runtime cost!
Examples
You can see simple example projects using next-urql in the examples directory or on CodeSandbox.
Caveats
withUrqlClient implements Next's unique getInitialProps method under the hood. This means that any page containing a component wrapped by withUrqlClient will be opted out of automatic static optimization. Automatic static optimization was added in Next v9, so you shouldn't worry about this if using an earlier version of Next. This is not unique to next-urql – any implementation of getInitialProps by any component in your application will cause Next to opt out of automatic static optimization.