What is a Waterline adapter

Summary

This lesson dives into Waterline adapters and their role in Sails.js. Adapters are what allow models in a Sails app to connect and interact with databases or datastores. Since Waterline handles the "M" (Model) in the MVC framework of Sails, each model requires an adapter to point it to the corresponding database. Adapters act as the bridge between your models and the underlying database, ensuring that calls like User.find() or User.create() are translated into the necessary database queries. Many adapters, such as those for Redis, PostgreSQL, and MySQL, are officially maintained by the Sails core team.

Transcript

All right. So in the previous lesson, we talked about Waterline being an adapter-based ORM for Sails. So what are these adapters, and how does Waterline interoperate with adapters? So what happens is, recall Sails is an MVC framework, right? And I told you before that Waterline handles the M in the MVC. So the models in your Sails app are going to have to talk to the underlying database or datastore, right?

So your models are JavaScript files, and they need to point to a defined database. So that's what this adapter provides, or these adapters provide. So when you do something like you say User.find(), what happens next is up to the adapter, which is going to work behind the scenes. So every model definitely is going to need an adapter, which points that model to a respective database or datastore.

So there are a couple of adapters already in existence in the Sails ecosystem. Some of them are maintained first-party wise and officially by the Sails core team, like the adapter for Redis, PostgreSQL, and MySQL. So that's what an adapter is in Waterline and Sails.

It gives your model the ability to interact with databases. So you call it an adapter or a database adapter. What that means is that when I do, like, maybe User.create() and my adapter is a PostgreSQL adapter, what happens is that once I call the .create() method in the User model, the underlying adapter is going to write an INSERT SQL statement in order to create whatever I'm trying to create at the time.

So that's what Waterline adapters or what database adapters are in relation to Waterline, the ORM, and Sails, the framework.