Indexing in Algolia using serverless functions (and observables!)
Written by Knut Melvær
2021-03-30: This article uses Webtask which now has been sunset. You can still read it to learn how to use observables in serverless functions. However, we recommend using our Sanity-Algolia toolkit for indexing content from your Sanity Content Lake in Algolia.
<Movie trailer voice>
In a world where monoliths break up, devs build new exciting services with towering JAMstacks, serverless functions, and epic cloud services. Yet they face one challenge: Moving data from one service to another. Introducing Observables. The code pattern that takes streams of data, mutate it to your liking, and pipe it effortlessly to another place. Coming soon to a code editor near you.
</Movie trailer voice>
With Sanity’s powerful export API it's easy to make a small serverless function in order to index all your content in Algolia for the times you want to harness its search capabilities. It's also a nice way to learn about observables in JavaScript.
Algolia is a powerful search-as-a-service that makes it easy to provide weighted searches, statistics, and rich user interfaces for search for your frontends. Webtask by Auth0 is a service that makes it easy to build serverless functions right in the browser. In this tutorial we will look closer on how we can use Sanity’s export API to quickly get the content you want to index into Algolia using a scheduled serverless function.
Setting up Algolia and getting some API keys
First you'll have to sign up for an account at Algolia. It should be pretty straightforward. Once you've set up an account go to API keys in the sidebar. You should be able to do this tutorial on the free plan, but note that there are some limits that may kick in at some point.
Have the keys available, because we're going to need them when we set up our serverless function.
Setting up a serverless function on webtask.io
There are many great services for setting up serverless functions: begin.com, code.xyz, Netlify functions, AWS Lambda, Now, Google Cloud Functions, the list could go on. For this tutorial we'll use webtask.io because it easy to set up, runs in the browser, and has scheduling as a feature. It shouldn't be too much work adapting this code to other services though.
Add secret tokens
Go to webtask.io/make, log in and make a new function from an empty template. Go to the 🔧wrench menu and choose secrets and Add Secret.
Call your "secret key" ALGOLIA_TOKEN and copy-paste your Admin API Key from Algolia into the "secret value" field. In other words: You should be careful with where you save this. This key will now be available under context.secrets.ALGOLIA_TOKEN in your function.