Calling REST API

In this section, you’ll learn how to access TMDB API to fetch popular movies.

What is an API?

API is an acronym for Application Programming Interface. An API lets two applications talk to each other.

The Movie DB contains information about popular movies and TV shows. API is the way to facilitate the app to fetch information from this big movie data storage into our application.

API key

An API key is a unique identifier given to a user, app, or developer to be able to make API requests. It is used to track the number of requests made by the app.

In the code, we’ll be using a variable apiKey to store the API key to access TheMovieDB API.

final apiKey = "YOUR_API_KEY";

First, you’ll need to get an API key for yourself. You need this to be able to make API requests to TMDB servers. Once you have your own API key, don’t forget to replace it with “YOUR_API_KEY”.

Getting an API key

Follow these steps to request an API key from TMDB API:

• Create a free account here.
• Check your email to verify your account.
• Visit the API Settings page in your Account Settings and request an API key. You should now have an API key and be ready to go!
• Update API key in code.

Accessing API

Now that you have your API key, keep it safe & handy to use in your code later for “YOUR_API_KEY”.

Configuration

Flutter uses the http Flutter package to make HTTP requests.

Adding package in pubspec.yaml

Add this package under the dependencies section. Be careful about indenting yaml file:

dependencies:
  flutter:
    sdk: flutter
  http: ^0.12.0+1

Importing the package

We’ll be making HTTP requests from code to fetch remote movie data. To do so, we need the Dart’s http package available to the code.

Import the http package in your code. Use the library prefix as for readability.

import 'package:http/http.dart' as http;

API endpoint

An endpoint is a place where the resource lives and where an API sends requests. Usually, an endpoint is a URL of the service.

The API endpoint or URL to request the most popular movies is /discover/movie?sort_by=popularity.desc

Replace YOUR_API_KEY with your own key generated in last lesson.

final apiKey = "YOUR_API_KEY";
final apiEndPoint =
"http://api.themoviedb.org/3/discover/movie?api_key=${apiKey}&sort_by=popularity.desc";

Your endpoint is ready to make an HTTP request.

Make HTTP Request

The package http imported earlier is used to make the HTTP request in the code snippet below.

The await keyword is used to make network calls asynchronously without blocking the main thread.

The following code returns the API response of HttpResponse type. Printing it will print a text string ‘Instance of Response.’

import 'package:http/http.dart' as http;

final apiResponse = await http.get(apiEndPoint);

Run code

At this point, we’ll print apiResponse fetched from API. It’ll simply print ‘Instance of Response’ on the screen.

Look out for the //NOTE comment(s).

Don’t forget to replace YOUR_API_KEY with your own API key to make requests to the TMDB API.

Please note that Android Emulator might take longer (~3 minutes) to start.