[SOLVED] How to insert layout meta info into all files matching a file pattern?

How to insert layout meta info into all files matching a file pattern?

I have lots of markdown source files, which are automatically generated by some data export step.

I'm using metalsmith-layouts and have e.g. these lines on top of my handcrafted (not automatically generated) markdown files in order to layout them using my layout.html:

---
layout: layout.html
title:  Downloads
---

How can I add the layout info dynamically to all files that match for example a file pattern tutorials/*.md, so that those files are also rendered with my layout? Adding this info to the files before conversion wouldn't be elegant.

Solution

I found it out meanwhile. It's possible to define a default layout to a file pattern this way:

// Apply the default layout to all .html files
.use(layouts({
    engine: 'handlebars',
    default: 'layout.html',
    directory: 'layouts',
    pattern: '**/*.html'
}))