catalog.js

const SquareConnect = require("square-connect");
const admin = require("firebase-admin");
const functions = require("firebase-functions");

exports.catalog = functions.https.onRequest((request, response) => {
  admin.auth().verifyIdToken(request.body.idToken)
    .then(decodedToken =>
      admin.database()
      .ref(`/squareAccessToken/${decodedToken.uid}`)
      .once("value")
    ).then(userToken => {
      SquareConnect.ApiClient.instance.authentications["oauth2"]
                                      .accessToken = userToken.val();
      const catalogApi = new SquareConnect.CatalogApi();
      return catalogApi.listCatalog();
    }).then(catalog => {
      let formattedResponse = catalog.objects.map(elem =>
        axios.post(
          'https://firebasedynamiclinks.googleapis.com/v1/shortLinks?key=' +
          functions.config().web.key, {
            longDynamicLink:
              `https://[YOUR_UNIQUE_LINK].page.link/?` +
              `link=https://[YOUR_PROJECT_NAME].firebaseapp.com/checkout/` +
              `${uid.split(":")[1]}/${elem.item_data.variations[0].id}`,
            suffix: { option: "SHORT" }
        }).then(resp => ({
          name: elem.item_data.name,
          catalogId: elem.id,
          varId: elem.item_data.variations[0].id,
          price: elem.item_data.variations[0].item_variation_data.price_money,
          checkoutUrl: resp.data.shortLink
        }))
      );
      return Promise.all(formattedResponse);
    })
    .then(values => { response.json(values); })
    .catch(error => {
      console.log(error);
      response.send(error);
    });
});