Chronoblog (Gatsby) theme with RSS feed

Chronoblog is one of the Gatsby blogging themes. RSS feed can be used to get the latest posts for Github actions, dev.to, etc. The following steps can easily add it. Use a similar approach for other Gatsby themes.

Initial setup

Run the following commands to clone the repository and install the required packages.

npx gatsby new chronoblog-site https://github.com/Chronoblog/gatsby-starter-chronoblog
cd chronoblog-site
npm i gatsby-plugin-feed@2 gatsby-transformer-remark@3 gatsby-source-filesystem

GraphQL setup

Populate GraphQL fields to avoid null errors. Add canonical_url: http://example.com to content → links → frontmatter-placeholder → index.md file.

Gatsby config

Add plugin configurations in gatsby-config.js. Draft content, links, and placeholder post are skipped.

module.exports = {
  // ...
  plugins: [
    // ...
    {
      resolve: `gatsby-plugin-feed`,
      options: {
        query: `
          {
            site {
              siteMetadata {
                title
                description
                siteUrl
                site_url: siteUrl
              }
            }
          }
        `,
        feeds: [
          {
            serialize: ({ query: { site, allMarkdownRemark } }) => {
              return allMarkdownRemark.edges.map(edge => {
                return Object.assign({}, edge.node.frontmatter, {
                  description: edge.node.excerpt,
                  date: edge.node.frontmatter.date,
                  url: edge.node.frontmatter.canonical_url || edge.node.frontmatter.url,
                  guid: edge.node.frontmatter.canonical_url || edge.node.frontmatter.url,
                  custom_elements: [{ "content:encoded": edge.node.html }],
                })
              })
            },
            query: `
              {
                allMarkdownRemark(
                  filter: { 
                    frontmatter: {
                      draft: { ne: true },
                      link: { eq: null },
                      title: { ne: "Ghost Post" }
                    },
                  },
                  sort: { order: DESC, fields: [frontmatter___date] },
                ) {
                  edges {
                    node {
                      excerpt
                      html
                      fields { slug }
                      frontmatter {
                        title
                        canonical_url
                        date
                      }
                    }
                  }
                }
              }
            `,
            output: "/rss.xml",
            title: "RSS Feed",
          },
        ],
      },
    },
    {
      resolve: `gatsby-transformer-remark`
    },
  ],
  // ...
};

Gatsby node setup

Implement onCreateNode function in gatsby-node.js file

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

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

Npm scripts setup

Add serve script in package.json

{
  // ...
  "scripts": {
    // ...
    "serve": "gatsby serve"
  }
}

Demo

Run npm run build && npm run serve. RSS feed should be populated on http://localhost:9000/rss.xml page.