Working with Images in Markdown & MDX
When building Gatsby sites composed primarily of markdown or MDX, insertion of images can enhance the content. You can add images in multiple ways which will be explained below. If you’re new to Gatsby we recommend checking out the main tutorial first. The instructions also assume that you already have an existing Gatsby site running with either markdown or MDX.
Prerequisites
- A Gatsby project set up. (Need help creating one? Follow the Quick Start)
- Either markdown or MDX support added to your site. Follow the MDX instructions or markdown instructions.
Featured images with frontmatter metadata
In sites like a blog, you may want to include a featured image that appears at the top of a page. One way to do this is to grab the image filename from a frontmatter field and then transform it with gatsby-plugin-sharp
in a GraphQL query.
If you want to have a very detailed explanation of this, head to part 7 of the Gatsby tutorial. The tutorial uses MDX, the instructions below will use markdown for the most part. It more or less behaves the same though.
To start out, install the necessary plugins for gatsby-plugin-image.
Then, configure the various plugins in the gatsby-config
file.
Configuring for images and posts in the same directory
If your images are in the same directory as the markdown files, sourcing and resolving the images can be done in one configuration. For example, if your markdown files and images are located together in a src/content
directory, both content types will be automatically picked up by GraphQL as part of Gatsby’s data layer.
Then, in an example markdown file, add a field called featuredImage
:
The next step will be to incorporate the data into a template with a GraphQL query, which can be found later in this guide.
Configuring for images and posts in different directories
There are also occasions when you may want to source images from a different directory than where your markdown posts or pages are located, such as in an external /images
folder. You can set this up by specifying two distinct sources, one for the markdown files and the other for images:
Then, in a markdown file, the path to a featuredImage
would be relative to the page file (in this case, in an /images
directory up a level):
Querying for images from frontmatter
Now that you’ve sourced markdown and image data, you can query for featured images in GraphQL. If a filepath points to an actual image, it will be transformed into a File
node in GraphQL and then you can get the image data out of it by using the childImageSharp
field.
This can be added to the GraphQL query in a markdown template file. In this example, a Dynamic image is used to make a responsive image. The query below might be different to what you have in your blog post template, however the highlighted section will be relevant nevertheless:
In the blog post template, import the gatsby-plugin-image
package and pass the results of the GraphQL query into an <GatsbyImage />
component.
The code example above is just an example, adjust the <GatsbyImage />
portion to how you’d want to use it in your template.
Inline images with gatsby-remark-images
You may also include images in the markdown/MDX body itself. The plugin gatsby-remark-images comes in handy for this.
Start out by installing gatsby-remark-images
:
Configure the plugins in your gatsby-config
file. As with the previous example, either markdown or MDX can be used.
Using gatsby-transformer-remark
Put the gatsby-remark-images
plugin within the plugins
option field of gatsby-transformer-remark
.
Using gatsby-plugin-mdx
gatsby-remark-images
needs to be a sub-plugin of gatsby-plugin-mdx
, included in the gatsbyRemarkPlugins
array.
With the configurations above, you can use the default markdown syntax for images. They will be processed by sharp and appear as if you placed them in a gatsby-plugin-image
component.