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gatsby-remark-autolink-headers

Adds GitHub-style hover links to headers in your markdown files when they’re rendered.

This is a sub-plugin for gatsby-transformer-remark. As demoed below, add this plugin to the options of gatsby-transformer-remark.

Install

npm install gatsby-remark-autolink-headers

How to use

// In your gatsby-config.js
module.exports = {
  plugins: [
    {
      resolve: `gatsby-transformer-remark`,
      options: {
        plugins: [`gatsby-remark-autolink-headers`],
      },
    },
  ],
}

Note: if you are using gatsby-remark-prismjs, make sure that it’s listed after this plugin. Otherwise, you might face an issue described here: https://github.com/gatsbyjs/gatsby/issues/5764.

// good
{
  resolve: `gatsby-transformer-remark`,
  options: {
    plugins: [
      `gatsby-remark-autolink-headers`,
      `gatsby-remark-prismjs`,
    ],
  },
}

// bad
{
  resolve: `gatsby-transformer-remark`,
  options: {
    plugins: [
      `gatsby-remark-prismjs`, // should be placed after `gatsby-remark-autolink-headers`
      `gatsby-remark-autolink-headers`,
    ],
  },
}

Options

  • offsetY: Signed integer. Vertical offset value in pixels (optional)
  • icon: SVG shape inside a template literal or boolean false. Set your own svg or disable icon (optional)
  • className: String. Set your own class for the anchor (optional)
  • maintainCase: Boolean. Maintains the case for markdown header (optional)
  • removeAccents: Boolean. Remove accents from generated headings IDs (optional)
  • enableCustomId: Boolean. Enable custom header IDs with {#id} (optional)
  • isIconAfterHeader: Boolean. Enable the anchor icon to be inline at the end of the header text (optional)
  • elements: String array. Specify which type of header tags to link (optional)
// In your gatsby-config.js
module.exports = {
  plugins: [
    {
      resolve: `gatsby-transformer-remark`,
      options: {
        plugins: [
          {
            resolve: `gatsby-remark-autolink-headers`,
            options: {
              offsetY: `100`,
              icon: `<svg aria-hidden="true" height="20" version="1.1" viewBox="0 0 16 16" width="20"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg>`,
              className: `custom-class`,
              maintainCase: true,
              removeAccents: true,
              isIconAfterHeader: true,
              elements: [`h1`, `h4`],
            },
          },
        ],
      },
    },
  ],
}

By default, the anchor link has a class of anchor (see className option to change this name) on the element but has no additional styling. To make it fit your website, you’ll have to write some CSS to change the appeareance.

In your CSS you can specify this element, in this instance the anchor tag will appear red:

a.anchor {
  fill: "red";
}

Note: There are a variety of approaches to styling your Gatsby site, see styling documentation for more detail.