👋 Welcome to Intro to GraphQL with TypeScript!

Your GraphQL journey begins now! Ready to embark?

In this series, we'll start from scratch and build a full-fledged GraphQL server using the Spotify API.

In this lesson, we will:

• Learn about what we're building, and the technologies that help us build it
• Set up our project environment

What is GraphQL?

Let's begin with the most important question of the course. What is GraphQL?

GraphQL is the developer-friendly query language for the modern web. It transforms how apps fetch data from an API, enabling you to get exactly what you need with a single query—instead of wrangling responses from a patchwork of REST endpoints.

With a strongly typed schema at its core, GraphQL helps you define relationships between data across any number of systems, empowering you to focus on what your data can do instead of where it's stored.

Throughout this course, we're going to learn how GraphQL fits into our existing architecture and how it works with existing REST APIs and other data sources. We'll learn how to use queries, mutations, arguments, the schema, and resolvers in our GraphQL API. Get ready to roll up your sleeves, write some code, test your understanding, and build something cool! 🎶

Prerequisites

To follow along...

• You should be familiar with basic TypeScript programming concepts.
• You'll need Node installed (we recommend using the latest version) as well as an IDE (we're using Visual Studio Code).
• Concepts and keywords like import, map, and async should be familiar before starting up.

What we're building

Listen up! Ready to tune into what we're building in this course? Drumroll please! 🥁

If you couldn't tell from all those music-related cues, we're building a music catalog API called MusicMatcher that helps us find the right soundtrack for the right moment.

For this first iteration of MusicMatcher, we'll focus on playlists: showcasing featured playlists, listing a playlist's tracks, and adding tracks. In future courses, we'll add more features like pagination, authentication, intermediate schema design concepts, and federation.

Clone the repository

In the directory of your choice with your preferred terminal, clone the app's starter repository:

Project structure

Our project already contains the files we need to get started and run our server, but we'll work primarily out of the src package highlighted below.

Now, open the repository in your favorite IDE. (We're using Visual Studio Code!)

Let's build and run the app

In the terminal, navigate to the root of the directory and run the following command.

If all goes well, you'll see your installation complete and a message that ts-node-dev is waiting for changes to your ./src/index.ts file. There's nothing else to do here, because we don't have any code for ts-node-dev to run just yet.

Let's jump in!

💾 Data!

Throughout the course, we'll build the GraphQL API that serves (and updates) data for playlists and their tracks.

This mockup shows a grid of featured playlists. For each playlist, we can start to see which pieces of data we need: a name and a description.

We need even more data to create a view for a specific playlist.

Here we can see the specific elements that make up each track contained in a playlist: its name, link, duration, and whether it's considered explicit.

To represent these different pieces in GraphQL, we can think about our data as a collection of objects (such as playlists and tracks) and relationships between objects (such as each playlist having at least one track).

Now, if we think of each object as a node and each relationship as an edge between two nodes, we can envision our entire data model as a collection of nodes and edges. This is called our application's graph.

Practice

Key takeaways

• GraphQL enables precise data retrieval with a single query, eliminating the need to navigate multiple REST endpoints on the client app side.
• GraphQL enables us to build APIs by describing our data in terms of object types (nodes) and relationships (edges).

Up next

This is what GraphQL is made up of, but we still need to talk about HOW it actually works. In the next lesson, we'll jump into the basics and follow the journey of a GraphQL operation.