gatsby-node.js

const path = require("path");
const glob = require("glob");
const fs = require("fs");
const frontmatter = require("@github-docs/frontmatter");
const { v4: uuidv4 } = require("uuid");
const { createFilePath } = require("gatsby-source-filesystem");
const redirects = require("./src/redirects.json");
const leftNavTitle = require("./src/left-nav-title.json");

const ignorePaths = [];

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

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

  redirects.forEach(({ from, to }) => {
    createRedirect({
      fromPath: from,
      isPermanent: true,
      redirectInBrowser: true,
      toPath: to,
    });
  });

  const result = await graphql(`
    query {
      allMarkdownRemark(sort: { fields: frontmatter___order, order: ASC }) {
        edges {
          node {
            fields {
              slug
            }
            frontmatter {
              title
              metadesc
              canonical
              keywords
              social_share_summary
              social_share_desc
              social_share_image
              noindex
            }
          }
        }
      }
    }
  `);
  result.data.allMarkdownRemark.edges.forEach(({ node }, index) => {
    if (node.fields.slug.includes("-")) {
      const underscoreSlug = node.fields.slug.replace(/-/g, "_");

      createRedirect({
        fromPath: underscoreSlug,
        isPermanent: true,
        redirectInBrowser: true,
        toPath: node.fields.slug,
      });
    }
    createPage({
      path: node.fields.slug,
      component: path.resolve("./src/templates/page.jsx"),
      context: {
        slug: node.fields.slug,
        prev:
          index === 0
            ? null
            : result.data.allMarkdownRemark.edges[index - 1].node,
        next:
          index === result.data.allMarkdownRemark.edges.length - 1
            ? null
            : result.data.allMarkdownRemark.edges[index + 1].node,
      },
    });
  });
};

/* Create Header and Footer
/************************************************************************ */
exports.sourceNodes = async ({
  actions,
  createNodeId,
  createContentDigest,
}) => {
  const prepareNode = (obj, name) => {
    const data = {
      key: uuidv4(),
      value: JSON.stringify(obj),
    };
    const node = JSON.stringify(data);
    const nodeMeta = {
      id: createNodeId(`my-data-${data.key}`),
      parent: null,
      children: [],
      internal: {
        type: name,
        mediaType: "text/json",
        content: node,
        contentDigest: createContentDigest(data),
      },
    };

    const output = { ...data, ...nodeMeta };
    return output;
  };

  const { createNode } = actions;

  const getDirectories = (src) => glob.sync(`${src}/**/*`);
  const paths = getDirectories("./src/pages/docs")
    .filter((val) => val.slice(-3) === ".md")
    .map((val) => {
      const { data } = frontmatter(fs.readFileSync(val));
      const order = data.order || 200;
      return [val, order];
    })
    .sort((a, b) => Number(a[1]) - Number(b[1]))
    .map((val) => {
      let newVal = "";
      newVal = val[0].replace(/\.\/src\/pages/g, "");
      newVal = newVal.substring(0, newVal.length - 3);
      newVal =
        newVal.slice(-5) === "index"
          ? newVal.substring(0, newVal.length - 5)
          : newVal;
      return `${newVal}/`;
    })
    .filter((val) => !ignorePaths.includes(val));

  const output = {};

  paths.forEach((val) => {
    let split = val.split("/");
    split = split.filter((url) => url !== "");

    let current = output;
    split.forEach((part) => {
      if (current[part]) current[part] = current[part];
      else {
        current[part] = {};
        if (leftNavTitle[part]) {
          Object.keys(leftNavTitle[part]).forEach((key) => {
            if (val.indexOf(key) === 0) {
              //console.log(key);
              current[part] = { leftNavTitle: leftNavTitle[part][key] };
            }
          });
        }
      }
      current = current[part];
    });
    current.url = `/${split.join("/")}/`;
  });
  //console.log(output.docs)
  createNode(prepareNode(output.docs, "leftNavLinks"));
};

exports.createSchemaCustomization = ({ actions }) => {
  const { createTypes } = actions;
  createTypes(`
    type MarkdownRemark implements Node {
      pluginCreator___NODE: String
    }
  `);
};