Search And You Shall Find

Every blog should have a search box. Not because it’s necessary, but because it’s fun to implement.

A few weeks ago I ran across a small Javascript library called Lunr.js. It’s basically a small text indexer that can rank search results and it’s written entirely in Javascript, just the way I like it.

Setting up an index is really easy:

var searchIndex = lunr(function () {
  this.field('title', { boost: 10 })
  this.field('content')
});

Then you just add some documents to the index:

var doc = {
  id: "a-blog-post-title",
  title: "A Blog Post Title",
  content: "This is a crummy example blog post...",
};
searchIndex.add(doc);

Then you can search for it by simply calling searchIndex.search('crummy blog'); and that will return an array of objects with the properties ref and score.

ref is the id property of the indexed document and score is, well, how well it scored. The array will be sorted with the highest scoring result first in the array.

If you want you can supply a word list to the search index with words that should not be counted, but by default it has a list of common English words such as ‘and’ and ‘if’ so that they won’t be ranked and affect performance.

Overall, I’m very happy with it. I created the SearchManager and connected it to the CacheManager so that it rebuilds the index if a new post is created or one is edited. I also configured the CacheManager so that it does not cache URLs starting with /search. That way I won’t fill up my cache store with all different search results.

So, if browsing the archive isn’t your cup of tea, then get searching folks!