How to respond with different status codes in GraphQL?

In GraphQL, the HTTP status code for responses is typically set to 200 (OK) by default, regardless of the actual result of the GraphQL query or mutation. However, you might want to respond with different status codes to indicate specific outcomes or errors.

To respond with different status codes in GraphQL, you can leverage the HTTP response headers to provide additional information about the response. Here are some common scenarios and approaches:

  1. Error Handling: When an error occurs during query or mutation execution, you can include error information in the response and set an appropriate status code to indicate the error. For example, you can set the status code to 400 (Bad Request) for client errors or 500 (Internal Server Error) for server errors.
  2. Custom Status Codes: In some cases, you might want to introduce custom status codes to convey specific application-related information. You can include these custom status codes in the response headers along with relevant error or success messages.
  3. Unauthenticated or Unauthorized Access: When a client attempts to access a protected resource without proper authentication or authorization, you can respond with a 401 (Unauthorized) or 403 (Forbidden) status code to indicate that access is denied.
  4. Resource Not Found: If a client requests a resource that does not exist, you can respond with a 404 (Not Found) status code.
  5. Successful Requests with No Data: In some cases, a client’s GraphQL query might execute successfully, but no data is returned (e.g., when querying an empty list). In such cases, you can respond with a 204 (No Content) status code to indicate that the request was successful, but there is no data to return.

To set different status codes in your GraphQL server, the exact implementation may depend on the technology stack you are using. If you are using a popular GraphQL server library like Apollo Server, you can set the status code in the context or in the response object of the resolver.

For example, in Node.js with Apollo Server, you can set the status code in a resolver like this:

const { ApolloServer, gql } = require('apollo-server');

const typeDefs = gql`
  type Query {
    hello: String
  }
`;

const resolvers = {
  Query: {
    hello: () => {
      // Perform some logic and determine the status code
      const statusCode = 200;

      // Set the status code in the response
      // Apollo Server's context.res is an Express response object
      context.res.status(statusCode);

      return 'Hello, world!';
    },
  },
};

const server = new ApolloServer({ typeDefs, resolvers });

server.listen().then(({ url }) => {
  console.log(`Server ready at ${url}`);
});

Remember to handle status codes consistently and effectively in your GraphQL server to provide meaningful feedback to clients and adhere to standard HTTP practices.

error: Content is protected !!