get request react

1// Simple GET request using fetch
2fetch('https://api.npms.io/v2/search?q=react')
3  .then(response => response.json())
4  .then(data => this.setState({ data: data.feed }));

1/* React get method.  */
2
3componentWillMount(){
4    fetch('/getcurrencylist',
5    {
6        /*
7        headers: {
8          'Content-Type': 'application/json',
9          'Accept':'application/json'
10        },
11        */
12        method: "get",
13        dataType: 'json',
14    })
15    .then((res) => res.json())
16    .then((data) => {
17      var currencyList = [];
18      for(var i=0; i< data.length; i++){
19        var currency = data[i];
20        currencyList.push(currency);
21      }
22      console.log(currencyList);
23      this.setState({currencyList})
24      console.log(this.state.currencyList);
25    })
26    .catch(err => console.log(err))
27  }