Wsrtjtyk

I have developed a blog with Gatsby JS and I managed to add categories to each markdown file so that I can create pages by querying a specific category and list all the posts related to that category.
Now, I'm trying to add pagination to avoid an infinite list of posts inside each category page.

I have been following the official guide here: https://www.gatsbyjs.org/docs/adding-pagination/

And this is the code I came up with:

gatsby-node.js

const path = require('path')

const _ = require("lodash")

const { createFilePath } = require("gatsby-source-filesystem")



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

const {createPage} = actions



const articleTemplate = path.resolve(`src/templates/article.js`)

const categoryTemplate = path.resolve("src/templates/category.js")



return new Promise((resolve, reject) => {

    resolve(

      graphql(

          `

            {

                allMarkdownRemark(

                    sort: { order: DESC, fields: [frontmatter___date] }

                    limit: 2000

                ) {

                    edges {

                        node {

                            html

                            id

                            frontmatter {

                                path

                                title

                                categories

                            }

                        }

                    }

                }

            }



    `).then(result => {

        if (result.errors) {

            reject(result.errors)

        }



        const articles = result.data.allMarkdownRemark.edges

        const articlesPerPage = 6

        const numPages = Math.ceil(articles.length / articlesPerPage)



        //Creating a page for each article

        articles.forEach(({ node }) => {

            createPage({

            path: node.frontmatter.path,

            component: articleTemplate,

            //context: {}, // additional data can be passed via context

            })

        })



        // Categories pages:

        let categories = 

        // Iterate through each article, putting all found categories into `categories`

        _.each(articles, edge => {

            if (_.get(edge, "node.frontmatter.categories")) {

                categories = categories.concat(edge.node.frontmatter.categories)

            }

        })





        Array.from({ length: numPages }).forEach((category, _, i) => {

            createPage({

              path: i === 0 ? `/${_.kebabCase(category)}/` : `/${_.kebabCase(category)}/${i + 1}`,

              component: categoryTemplate,

              context: {

                limit: articlesPerPage,

                skip: i * articlesPerPage,

                category,

              },

            })

        })

    })

)

})

/templates/categories.js

import React from "react"

import PropTypes from "prop-types"

import Layout from '../layouts/layout'

import ArticleCard from '../components/articles/articlecard'



// Components

import { Link, graphql } from "gatsby"



const _ = require("lodash")



const Categories = ({ pageContext, data }) => {

  const { category } = pageContext

  const { edges } = data.allMarkdownRemark



  return (

    <Layout>

        <section class="hero is-info is-medium has-text-centered">

            <div class="hero-body">

                <div class="container">

                    <h1 class="title is-top">

                        {category}

                    </h1>

                </div>

            </div>

        </section>

        <div class="section">

            <div class="container">

                <div class="columns is-multiline">

                    {edges.map(({ node }) => {

                        const { path, title, date } = node.frontmatter

                        return (

                            <div class="column is-half">

                                <div class="card">

                                    <div class="card-header">

                                        <p class="card-header-content">{date}</p>

                                    </div>

                                    <div class="card-content">

                                    <Link to={_.kebabCase(category)}><span class="tag is-success has-padding">{category}</span></Link>

                                        <Link to={path}>

                                            <h2 class="title is-4">{title}</h2>

                                        </Link>

                                    </div>

                                    <div class="card-footer">

                                        <div class="card-footer-item"><Link to={path}><div class="button is-success is-inverted is-fullwidth">Read</div></Link></div>

                                        <div class="card-footer-item"><Link to={path}><div class="button is-info is-inverted is-fullwidth">Share on Linkedin</div></Link></div>

                                    </div>        

                                </div>

                            </div>

                        )

                    })}

                </div>

            </div>

        </div>

    </Layout>

  )

}



Categories.propTypes = {

  pageContext: PropTypes.shape({

    category: PropTypes.string.isRequired,

  }),

  data: PropTypes.shape({

   allMarkdownRemark: PropTypes.shape({

      totalCount: PropTypes.number.isRequired,

      edges: PropTypes.arrayOf(

        PropTypes.shape({

          node: PropTypes.shape({

            frontmatter: PropTypes.shape({

              path: PropTypes.string.isRequired,

              title: PropTypes.string.isRequired,

            }),

          }),

        }).isRequired

      ),

    }),

  }),

}



export default Categories



export const pageQuery = graphql`

  query($skip: Int!, $limit: Int!, $category: String) {

    allMarkdownRemark(

      sort: { fields: [frontmatter___date], order: DESC }

      filter: { frontmatter: { categories: { in: [$category] } } }

      limit: $limit

      skip: $skip

    ) {

      totalCount

      edges {

        node {

          frontmatter {

            title

            path

            date(formatString: "MMMM DD, YYYY")

          }

        }

      }

    }

  }

`

This does not work and it is now throwing the error: error gatsby-node.js returned an error, TypeError: _.kebabCase is not a function

However kebabCase was used smoothly before modifying the query to add pagination, so I don't think the problem is actually there.

Does anyone have any clue?

Thank you!