How to customize errors throwed from static queries?

[tadeas22]

Hello

is it possible to custom errors throwed from static queries? For instance i can customize schema to require field foo in siteMetadata .

exports.createSchemaCustomization = ({ actions }) => {
	const { createTypes } = actions;
	const typeDefs = `
          type SiteSiteMetadata implements Node {
            foo: String!
          }
        `;
	createTypes(typeDefs);
};

src/pages/index.js

export const query = graphql`
	{
		site {
			siteMetadata {
				foo
			}
		}
	}
`;

and i need throw custom error/exception when missing

now i am getting the following error and i want customize text to "Foo is required because it contains secret" for instance

...
error There was an error in your GraphQL query:

Cannot return null for non-nullable field SiteSiteMetadata.foo.

The field "SiteSiteMetadata.foo." was expli...

[LekoArts]

Hi, thanks for the question!

No, this isn't currently possible. Depending on how the information for foo comes in you could validate it's existence in the onPreBootstrap phase (you have access to plugin options there) or in the gatsby-config.js file itself (you can throw errors there).

If you're creating a plugin: https://www.gatsbyjs.com/docs/how-to/plugins-and-themes/configuring-usage-with-plugin-options/