gridsome.server.js

// Server API makes it possible to hook into various parts of Gridsome
// on server-side and add custom data to the GraphQL data layer.
// Learn more: https://gridsome.org/docs/server-api/

// Changes here require a server restart.
// To restart press CTRL + C in terminal and run `gridsome develop`

module.exports = function(api) {
  api.createPages(async ({ graphql, createPage }) => {
    const { data } = await graphql(`
      {
        gcms {
          graphcms {
            products {
              slug
            }
          }
        }
      }
    `);

    data.gcms.graphcms.products.forEach(node => {
      createPage({
        path: `/product/${node.slug}`,
        component: './src/templates/Product.vue',
        context: {
          slug: node.slug,
        },
      });
    });
  });
};