Countries GraphQL API
A public GraphQL API for information about countries, continents, and languages. This project uses Countries List as a data source, so the schema follows the shape of that data, with a few exceptions:
- The codes used to key the objects in the original data are available as a
codeproperty on each item returned from the API. - The
continentandlanguagesproperties are now objects and arrays of objects, respectively.
Querying
In:
{
country(code: "BR") {
name
native
emoji
currency
languages {
code
name
}
}
}
Out:
{
"data": {
"country": {
"name": "Brazil",
"native": "Brasil",
"emoji": "🇧🇷",
"currency": "BRL",
"languages": [
{
"code": "pt",
"name": "Portuguese"
}
]
}
}
}
Check out the playground to explore the schema and test out some queries.
Example
One practical use of this API is to create a country select field that fetches its options dynamically. Normally, you would need to install an npm package or create a file in your project containing the necessary data -- usually country codes and names -- and bundle that data with your app code. This results in a lot of extra kilobytes hanging around in your bundle for a feature that might not always get rendered or used. Here's what that data size looks like:
- 50.1 KB using the
countriesexport from Countries List - 14.2 KB using this API (~70% smaller)
In this example, I'll be using React and some Apollo tools. Apollo's GraphQL client and React components make it simple to execute, handle, and cache GraphQL queries. You can also accomplish this by sending a POST request to this API using fetch or your favourite request library, but I won't cover that in this example.
Install dependencies
$ npm install react react-dom react-apollo apollo-boost graphql graphql-tag
Build a React component
import ApolloClient from 'apollo-boost';
import React, {Component} from 'react';
import ReactDOM from 'react-dom';
import gql from 'graphql-tag';
import {Query} from 'react-apollo';
// initialize our Apollo GraphQL client
const client = new ApolloClient({
uri: 'https://countries.trevorblades.com'
});
// write a GraphQL query that asks for names and codes for all countries
const GET_COUNTRIES = gql`
{
countries {
name
code
}
}
`;
class App extends Component {
constructor(props) {
super(props);
// set a default value
this.state = {
country: 'US'
};
}
// set the selected country to the new input value
onCountryChange(event) {
this.setState({country: event.target.value});
}
render() {
return (
<Query query={GET_COUNTRIES} client={client}>
{({loading, error, data}) => {
if (loading) return <p>Loading...</p>;
if (error) return <p>{error.message}</p>;
return (
<select
value={this.state.country}
onChange={this.onCountryChange.bind(this)}
>
{data.countries.map(country => (
<option key={country.code} value={country.code}>
{country.name}
</option>
))}
</select>
);
}}
</Query>
);
}
}
ReactDOM.render(<App />, document.getElementById('root'));