Add Custom Header To Apollo Client Polling Request

Are you using Apollo Client for managing your GraphQL interactions and wondering how to customize the headers in your polling requests? Well, you've come to the right place! Adding a custom header to an Apollo Client polling request is a useful feature that can help you enhance the security and functionality of your application. Let's dive into how you can easily achieve this.

When it comes to Apollo Client, polling allows your application to continuously retrieve updated data from your GraphQL server at specified intervals. By including custom headers in these polling requests, you can pass along additional information to authenticate, authorize, or identify the request.

To start, you need to define a new instance of the `ApolloClient` with your desired custom headers. The `createHttpLink` method from the `@apollo/client` package enables you to create a new HTTP link with custom configurations.

Here's a basic example of how you can add custom headers to your Apollo Client polling request:

import { ApolloClient, InMemoryCache, createHttpLink } from '@apollo/client';
import { setContext } from '@apollo/client/link/context';

const httpLink = createHttpLink({
  uri: 'YOUR_GRAPHQL_ENDPOINT',
});

const authLink = setContext((_, { headers }) => {
  const customHeaders = {
    Authorization: `Bearer YOUR_ACCESS_TOKEN`,
    // Add other custom headers here
  };

  return {
    headers: {
      ...headers,
      ...customHeaders,
    },
  };
});

const client = new ApolloClient({
  link: authLink.concat(httpLink),
  cache: new InMemoryCache(),
});

In this code snippet, we first create an `httpLink` that points to your GraphQL endpoint. Next, we define an `authLink` using the `setContext` function to include our custom headers, such as an authorization token. Finally, we create a new `ApolloClient` instance by combining the `authLink` and `httpLink`.

With these simple steps, you have successfully added custom headers to your Apollo Client polling requests. Remember to replace `'YOUR_GRAPHQL_ENDPOINT'` with the actual endpoint of your GraphQL server and `'YOUR_ACCESS_TOKEN'` with your valid access token.

By incorporating custom headers into your polling requests, you can ensure that your application communicates securely and efficiently with your GraphQL server. Whether you need to pass authentication tokens, user identifiers, or any other custom data, this feature gives you the flexibility to tailor your requests according to your specific requirements.

Now that you have this knowledge in your toolkit, feel free to explore more ways to customize and optimize your Apollo Client setup. Happy coding!