Delve into building a GraphQL endpoint with Deno, compare technologies, configure queries, and integrate PostgresSQL and MongoDB databases to create a secure, high-performing application.

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Deno is a modern and secure runtime for JavaScript. It was created by the same team that created Node.js. Deno offers better performance, security, and simplicity than any other JavaScript runtime.

In this course, you will start by understanding the different technologies used in Deno, such as Typescript. You will compare these technologies with JavaScript and GraphQL as well as learn their terminologies. Then, you will create your own endpoint with Deno and configure queries and mutations in it. Next, you will explore two different databases with Deno: first, you’ll learn how to set up an SQL database using PostgresSQL and then how to configure a NoSQL database using MongoDB to store documents and collections of on-demand data. Finally, you’ll put everything together to have a fully functioning GraphQL endpoint made with Deno and backed by PostgreSQL and MongoDB. 

After this course, you’ll be able to create a Deno application and a GraphQL endpoint while having a database of your choice to store data.

Building a GraphQL Endpoint with Deno

**GraphQL** is a query language that lets us describe the data we want to receive from the API. It gives the client the ability to ask for exactly what they need.

In the illustration below, the GraphQL server returns the exact fields our application is asking for, even though the `Book` entity has other fields.

Meta (formerly known as Facebook) developed GraphQL in 2012 before being publicly released in 2015. In 2019, it became a foundation. Today, it’s hosted by the Linux foundation, along with other GraphQL projects like GraphiQL, GraphQL.js, Node.js, and many others.

# Motivation behind GraphQL

The motivation behind GraphQL was pretty simple: the team at Meta had encountered many problems when trying to get a Facebook user’s news feed. This was because the shape of data was different between what was implemented in the backend and what front-end teams assumed it would be. It was also due to the problems related to underfetching and overfetching.

By working with GraphQL, some of the complexity is moved from the server-side to the client-side, which can be a very good thing for the developer. Many of the mobile phones we use today are more powerful than the PCs we had years ago, which is amazing for us, because now we rely less on the server’s computing power, subsequently lowering the cost of infrastructure. This decrease in reliability on the server-side depends on the type of application we’re working on, our target audience, and the sensitivity of our data, among other things.


Learn about the motivations behind the invention of GraphQL.

Introduction to Deno, TypeScript, and GraphQL

Creating a Basic GraphQL Endpoint

Databases and Deno

SQL: Postgres and Deno

NoSQL: Mongo and Deno

Wrapping Up

Appendix

What is GraphQL?

Motivation behind GraphQL