Getting the categories

3.4-gatsby-node.js

const kebabCase = require(`lodash.kebabcase`)

const allCategories = Object.keys(countCategories)

allCategories.forEach((cat, i) => {
  const link = `/blog/category/${kebabCase(cat)}`

  Array.from({
    length: Math.ceil(countCategories[cat] / postsPerPage),
  }).forEach((_, i) => {
    createPage({
      path: i === 0 ? link : `${link}/page/${i + 1}`,
      component: blogCategoryLayout,
      context: {
        allCategories: allCategories,
        category: cat,
        limit: postsPerPage,
        skip: i * postsPerPage,
        currentPage: i + 1,
        numPages: Math.ceil(countCategories[cat] / postsPerPage),
      },
    })
  })
})