TypeError when using firebase

import firebase from 'firebase/app';

export default {

    props: {
        authApi: {type: Object, required: true}
    },
    methods: {
        googleSignIn: function() {
            const provider = new firebase.auth.GoogleAuthProvider();
            console.log(firebase);
            firebase
                .auth()
                .signInWithPopup(provider)
                .then((result) => {
                    const token = result.credential.accessToken;
                    const user = result.user;
                    console.log(token); // Token
                    console.log(user); // User that was authenticated
                })
                .catch((err) => {
                    console.log(err); // This will give you all the information needed to further debug any errors
                });
        }
    }
};

import firebase from 'firebase/app';

export default {

    props: {
        authApi: {type: Object, required: true}
    },
    methods: {
        googleSignIn: function() {
            const provider = new firebase.auth.GoogleAuthProvider();
            console.log(firebase);
            firebase
                .auth()
                .signInWithPopup(provider)
                .then((result) => {
                    const token = result.credential.accessToken;
                    const user = result.user;
                    console.log(token); // Token
                    console.log(user); // User that was authenticated
                })
                .catch((err) => {
                    console.log(err); // This will give you all the information needed to further debug any errors
                });
        }
    }
};

[Vue warn]: Error in v-on handler: "TypeError: firebase_app__WEBPACK_IMPORTED_MODULE_0__.default is undefined"

found in

---> <Auth> at src/controllers/auth.vue
       <App> at node_modules/@trikoder/trim/src/js/components/appView.vue
         <Root>

[Vue warn]: Error in v-on handler: "TypeError: firebase_app__WEBPACK_IMPORTED_MODULE_0__.default is undefined"

found in

---> <Auth> at src/controllers/auth.vue
       <App> at node_modules/@trikoder/trim/src/js/components/appView.vue
         <Root>

const firebaseConfig = {
//firebase config stuff
};
initializeApp(firebaseConfig);

const firebaseConfig = {
//firebase config stuff
};
initializeApp(firebaseConfig);