gatsby-node.js

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

// You can delete this file if you're not using it
const path = require("path")
const { createFilePath } = require("gatsby-source-filesystem")
const { fmImagesToRelative } = require("gatsby-remark-relative-images")

exports.createPages = ({ graphql, actions }) => {
  const { createPage } = actions

  return new Promise((resolve, reject) => {
    resolve(
      graphql(
        `
          {
            allMarkdownRemark(
              sort: { fields: [frontmatter___date], order: DESC }
              filter: { frontmatter: { templateKey: { eq: "actualites" } } }
              limit: 1000
            ) {
              edges {
                node {
                  fields {
                    slug
                  }
                }
              }
            }
          }
        `
      ).then(result => {
        if (result.errors) {
          reject(result.errors)
        }

        // Create blog-list pages
        const posts = result.data.allMarkdownRemark.edges
        const postsPerPage = 6
        const numPages = Math.ceil(posts.length / postsPerPage)
        Array.from({ length: numPages }).forEach((_, i) => {
          createPage({
            path: i === 0 ? `/actualites` : `/actualites/${i + 1}`,
            component: path.resolve("./src/components/news-list.js"),
            context: {
              limit: postsPerPage,
              skip: i * postsPerPage,
              numPages,
              currentPage: i + 1,
            },
          })
        })
      })
    )
  })
}

exports.onCreateNode = ({ node, actions, getNode }) => {
  const { createNodeField } = actions
  fmImagesToRelative(node) // convert image paths for gatsby images

  if (node.internal.type === `MarkdownRemark`) {
    const value = createFilePath({ node, getNode })
    createNodeField({
      name: `slug`,
      node,
      value,
    })
  }
}