gatsby-node.js

/**
 * Implement Gatsby's Node APIs in this file.
 *
 * See: https://www.gatsbyjs.org/docs/node-apis/
 */

const path = require(`path`);

exports.onCreateNode = ({ node, boundActionCreators }) => {
  const { createNodeField } = boundActionCreators;
  if (node.internal.type === `PrismicDocument`) {
    if (node.type == 'page') {
      const slug = '/' + node.uid;
      createNodeField({
        node,
        name: `slug`,
        value: slug,
      });
    }
  }
};

exports.createPages = ({ graphql, boundActionCreators }) => {
  const { createPage } = boundActionCreators;
  return new Promise((resolve, reject) => {
    graphql(`
      {
        allPrismicDocument(filter: { type: { eq: "page" } }) {
          edges {
            node {
              fields {
                slug
              }
            }
          }
        }
      }
    `
).then(result => {
      result.data.allPrismicDocument.edges.forEach(({ node }) => {
        createPage({
          path: node.fields.slug,
          component: path.resolve(`./src/templates/page.js`),
          context: {
            // Data passed to context is available in page queries as GraphQL variables.
            slug: node.fields.slug,
          },
        })
      })
      resolve();
    })
  })
};