Javascript – TypeError: loadData.getData is not a function

I’m trying to fetching json file format from url, But I want the function inside of a class, but I got an undefined thing on output, here’s all my codes:

const axios = require('axios');

var BASE_URL = 'https://estra-api.herokuapp.com/'


class loadData {
    constructor() {
        self.sfw = {};
        self.nsfw = {};
    }
    getData(){
        axios.get(BASE_URL)
        .then(function data (response) {
            return response.data["link"]
        })
    }
}
console.log(loadData.getData())

My Output errors was

console.log(loadData.getData())
                     ^

TypeError: loadData.getData is not a function
    at Object.<anonymous> (C:UsersStawaDesktopEstraMainAPIEstraJS-APIindex.js:20:22)
    at Module._compile (internal/modules/cjs/loader.js:1085:14)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1114:10)
    at Module.load (internal/modules/cjs/loader.js:950:32)
    at Function.Module._load (internal/modules/cjs/loader.js:790:12)
    at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:76:12)
    at internal/main/run_main_module.js:17:47

I have tried to use console.log(loadData.getData) it just give me output undefined