Handlebars-helper-compose NPM

{{compose}} handlebars helper. Inlines content from multiple files optionally using wildcard (globbing/minimatch) patterns, extracts YAML front matter to pass to context for each file. Accepts compare function as 3rd parameter for sorting inlined files.

Quickstart

In the root of your project, run the following in the command line:

npm i handlebars-helper-compose --save-dev

Next, in your Gruntfile, simply add handlebars-helper-compose to the helpers property in the Assemble task or target options:

grunt.initConfig({
  assemble: {
    options: {
      // the 'handlebars-helper-compose' modules must also be listed in devDependencies
      // for assemble to automatically resolve the helper
      helpers: ['handlebars-helper-compose']
    }
    files: {
      '_gh_pages/': ['templates/*.hbs']
    }
  }
});

With that completed, you may now use the {{compose}} helper in your templates:

{{compose src="blog/posts/*.md"}}
  <h1>Title: {{@title}}</h1>
  {{{@content}}}</p>
{{/compose}}

Note that the path used in the src hash option is relative to the project root (e.g. Gruntfile).

Context & Lo-Dash templates

The helper will also process any valid Lo-Dash templates in the YAML front matter of any targeted files. For example:

---
title: <%= blog.title %>
post: 1
heading: <%= blog.title %> | Blog <%= post %>
---
<h1>{{title}}</h1>
<p class="heading">{{heading}}</p>

Options

src

Type: String (optional)

Default: undefined

The file path of the file(s) to include. Glob patterns may be used.

cwd

Type: String (optional)

Default: undefined

The cwd for paths defined in the helper.

sep

Type: String

Default: \n

The separator to append after each inlined file.

marked

Type: Object

Default: \n

The separator to append after each inlined file.

filter

Type: function

Default: undefined

A custom function for filtering the array of paths returned from the src property. This could potentially be more flexible, please make a feature request if you have a use case.

compare

Type: Function

Default: function(a, b) {return a.index >= b.index ? 1 : -1;}

Compare function for sorting the aggregated files.

Defining options

"assemble" task options

If you use Grunt and Assemble, you can pass options from the assemble task in the Gruntfile to the helper.

In your project's Gruntfile, options for the {{#compose}}...{{/compose}} helper can be defined in the Assemble task options:

assemble: {
  options: {
    helpers: ['handlebars-helper-compose', 'foo/*.js'],
    compose: {
      cwd: './posts',
      sep: '<!-- post -->',
      compare: function(a, b) {
        return a.index >= b.index ? 1 : -1;
      }
    }
  },
  files: {}
}

Note that the options are defined in options: {compose: {}}, which is registered by this helper as a custom property in the Assemble options.

Examples

all options

assemble: {
  options: {
    compose: {
      cwd: 'posts',
      sep: '<!-- post -->',
      compare: function(a, b) {
        return a.index >= b.index ? 1 : -1;
      }
    }
  }
}

filtering

Example: return only the last two items from the src files array:

assemble: {
  options: {
    compose: {
      cwd: 'posts',
      sep: '<!-- post -->',
      filter: function(arr) {
        return arr.slice(Math.max(arr.length - 2, 0));
      }
    }
  }
}

cwd option

Instead of defining the entire path in the src hash option, like this:

{{compose src="path/to/my/blog/posts/*.md"}}
  <h1>{{@title}}</h1>
  {{@content}}
{{/compose}}

You could define the cwd in the compose options in your project's Gruntfile:

assemble: {
  options: {
    helpers: ['helper-compose'],
    compose: {
      cwd: 'path/to/my/blog'
    }
  }
}

and then define paths in the templates like this:

{{compose 'posts/*.md'}}
  <h1>{{@title}}</h1>
  {{@content}}
{{/compose}}

Usage example

In our Gruntfile, let's say we have the following config:

// Project configuration.
grunt.initConfig({

  // Metadata for our blog.
  blog: require('./test/fixtures/blog/blog.yml'),
  assemble: {
    options: {
      helpers: ['handlebars-helper-compose'],
      compose: {
        cwd: 'blog',
        sep: '<!-- post -->'
      }
    },
    blog: {
      src: ['index.hbs'],
      dest: 'blog/'
    }
  }
});

page

...and index.hbs file contains the following:

<!-- post -->
{{#compose src="posts/*.md" sep="<!-- post -->"}}
  <h1>{{blog.title}}</h1>
  <h2>Post title: {{@title}}</h2>
  <p>{{{@content}}}</p>
{{/compose}}

posts

..and we have a few posts, monday.md, tuesday.md, and wednesday.md, for example:

---
title: Monday
---

This is the {{title}} post...

result

The result, blog/index.html would look something like:

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8">
    <title>My Brilliant Blog</title>
  </head>
  <body>

    <!-- post -->
    <h1>My Brilliant Blog</h1>
    <h2>Post title: Monday</h2>
    <p>This is the Monday post...</p>

    <!-- post -->
    <h1>My Brilliant Blog</h1>
    <h2>Post title: Tuesday</h2>
    <p>This is the Tuesday post...</p>

    <!-- post -->
    <h1>My Brilliant Blog</h1>
    <h2>Post title: Wednesday</h2>
    <p>This is the Wednesday post...</p>
  </body>
</html>