Golang-How to parse JSON data into a nested struct

Say you are fetching data from a RESTful API using GET requests and want to store the JSON responses. One of the ways to achieve this is by parsing the JSON data into a Go struct. The following example will fetch data related to standings of a football league, UEFA Champions League in this case.

RESTful API used : https://www.football-data.org/
You’ll need a free API key to access the data.

Construct a blueprint of the struct:
Here’s a useful tool that converts JSON to a Go struct type. I have removed a few fields to make the struct simpler. Each field is associated with a JSON tag.

Construct separate struct types for JSON objects that are arrays. In the following example a separate type is constructed for Standing and Table and the fields Standings is a slice of Standing i.e. []Standing and Tables is a slice of Table i.e. []Table .

Get JSON data from the API:
GetData function returns a slice of byte. It does the following tasks:
* Makes an HTTP GET request;
* Sets the “X-Auth-Token” in request header;
* Sets up an HTTP Client that makes an HTTP request and returns an HTTP response, following the auth-token as configured.
* Reads HTTP response body that contains JSON data and converts it to a []byte.

The []byte returned can be used to parse JSON encoded data into any struct type using json.Unmarshal.

Parse JSON into Competitions struct:
GetStandings function takes the league id as an argument to build the final url and returns a Competitions struct that has the parsed JSON data in it.

json.Unamrshal parses the JSON-encoded data that is in []byte and stores the result in the struct whose address is given by &s .

Note: To make successful GET requests, set the variable apikey.

Voila!
Print the struct on terminal using the format verb %+v variant that will include the struct’s field names or use package spew that prints some additional information about the struct.