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Example demonstates How to call REST API which supports GET Method? & How to convert response JSON to Object?
func main() {
// mapping json keys to the struct fields.
// Make sure first character of each field value is uppercase,
// otherwise mapping will not work
type User struct {
Id int `json:"id"`
Email string `json:"email"`
FirstName string `json:"first_name"`
LastName string `json:"last_name"`
Avatar string `json:"avatar"`
}
// mapping json keys to the struct fields.
// Make sure first character of each field value is uppercase,
// otherwise mapping will not work.
// We are taking this struct as json is nested object
// where "data" is the key for inner object.
type Data struct {
User User `json:"data"`
}
var data Data
/*response from dummy API: {
"data":{
"id":7,
"email":"michael.lawson@reqres.in",
"first_name":"Michael",
"last_name":"Lawson",
"avatar":"https://s3.amazonaws.com/uifaces/faces/twitter/follettkyle/128.jpg"
}
}
*/
response, err := http.Get("http://reqres.in/api/users/7")
if err != nil {
fmt.Printf("Request Failed %s\n", err) // print error if err is not empty
} else {
// json.Decode can also be used to do this conversion.
// Declared blank identifier("_") to avoid unused variables
// from the returns values.
jsonData, _ := ioutil.ReadAll(response.Body)
// print response as json string
fmt.Printf("%s\n", jsonData)
// there are many ways to do this
json.Unmarshal(jsonData, &data)
// print struct values with field name
fmt.Printf("%+v", data.User)
}
}
{
"data": {
"id": 7,
"email": "michael.lawson@reqres.in",
"first_name": "Michael",
"last_name": "Lawson",
"avatar": "https://s3.amazonaws.com/uifaces/faces/twitter/follettkyle/128.jpg"
}
}
{
Id:7 Email:michael.lawson@reqres.in
FirstName:Michael
LastName:Lawson
Avatar:https://s3.amazonaws.com/uifaces/faces/twitter/follettkyle/128.jpg
}
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