[](https://deploy.now.sh/?repo=https://github.com/zeit/next.js/tree/master/examples/with-apollo-auth)
Execute [`create-next-app`](https://github.com/segmentio/create-next-app) with [Yarn](https://yarnpkg.com/lang/en/docs/cli/create/) or [npx](https://github.com/zkat/npx#readme) to bootstrap the example:
> [Apollo](https://www.apollographql.com/client/) is a GraphQL client that allows you to easily query the exact data you need from a GraphQL server. In addition to fetching and mutating data, Apollo analyzes your queries and their results to construct a client-side cache of your data, which is kept up to date as further queries and mutations are run, fetching more results from the server.
> In this simple example, we integrate Apollo seamlessly with Next by wrapping our *pages* inside a [higher-order component (HOC)](https://facebook.github.io/react/docs/higher-order-components.html). Using the HOC pattern we're able to pass down a central store of query result data created by Apollo into our React component hierarchy defined inside each page of our Next application.
> On initial page load, while on the server and inside `getInitialProps`, we invoke the Apollo method, [`getDataFromTree`](https://www.apollographql.com/docs/react/features/server-side-rendering.html#getDataFromTree). This method returns a promise; at the point in which the promise resolves, our Apollo Client store is completely initialized.
> *Note: If you're interested in integrating the client with your existing Redux store check out the [`with-apollo-and-redux`](https://github.com/zeit/next.js/tree/master/examples/with-apollo-and-redux) example.*
[graph.cool](https://www.graph.cool) can be setup with many different
[authentication providers](https://www.graph.cool/docs/reference/integrations/overview-seimeish6e/#authentication-providers), the most basic of which is [email-password authentication](https://www.graph.cool/docs/reference/simple-api/user-authentication-eixu9osueb/#email-and-password). Once email-password authentication is enabled for your graph.cool project, you are provided with 2 useful mutations: `createUser` and `signinUser`.
On loading each route, we perform a `user` query to see if the current visitor is logged in (based on a cookie, more on that in a moment). Depending on the query result, and the route, the user may be [redirected](https://github.com/zeit/next.js/blob/master/examples/with-apollo-auth/lib/redirect.js) to a different page.
When creating an account, both the `createUser` and `signinUser` mutations are executed on graph.cool, which returns a token that can be used to [authenticate the user for future requests](https://www.graph.cool/docs/reference/auth/authentication-tokens-eip7ahqu5o/). The token is stored in a cookie for easy access (_note: This may have security implications. Please understand XSS and JWT before deploying this to production_).
A similar process is followed when signing in, except `signinUser` is the only mutation executed.
It is important to note the use of Apollo's `resetStore()` method after signing in and signing out to ensure that no user data is kept in the browser's memory.
To get this example running locally, you will need to create a graph.cool
account, and provide [the `project.graphcool` schema](https://github.com/zeit/next.js/blob/master/examples/with-apollo-auth/project.graphcool).
In these *with-apollo* examples, the ```withData()``` HOC must wrap a top-level component from within the ```pages``` directory. Wrapping a child component with the HOC will result in a ```Warning: Failed prop type: The prop 'serverState' is marked as required in 'WithData(Apollo(Component))', but its value is 'undefined'``` error. Down-tree child components will have access to Apollo, and can be wrapped with any other sort of ```graphql()```, ```compose()```, etc HOC's.
