gatsby-plugin-folder-metadata

While building a large and complex website, I ran into a situation where I wanted to be able to have metadata that applied to every file within a folder. This plugin reads in metadata.json files and adds them to the metadata.data field on Gatsby File nodes.

If a parent folder has metadata, it's included under the metadata.parent field. This allows a single node to respond to all metadata that may be relevant. For instance, this allows metadata to be used to assign a different path to be used when generating pages from a folder's contents.

For instance, for .mdx files, you can query the metadata generated by this plugin with

query YourQuery {
  allMdx {
    edges {
      node {
        parent {
          ... on File {
            fields {
              metadata {
                data {
                  your
                  json
                  keys
                }
              }
            }
          }
        }
      }
    }
  }
}

It's verbose and a little awkward, but it means that the only requirement for using this plugin is using source plugins that generate File nodes. This lets it compose well with other plugin without knowledge of them.