add types. TODO make logic match desired types.

src/mollie.ts

@@ -1,21 +1,22 @@
 "use strict";
 import { mergeMap } from "rxjs/operators";
-import { of, from, concat } from "rxjs";
+import { of, from, concat, Observable } from "rxjs";
+import { List, MollieClient, MollieOptions, Payment } from "@mollie/api-client";
 
 export const mollieKeys = {
-    leden: process.env.MOLLIE_API_KEY_LEDEN,
-    doemee: process.env.MOLLIE_API_KEY_DOEMEE,
-    shop: process.env.MOLLIE_API_KEY_SHOP,
-    doneer: process.env.MOLLIE_API_KEY_DONEER,
+    leden: process.env.MOLLIE_API_KEY_LEDEN || '',
+    doemee: process.env.MOLLIE_API_KEY_DOEMEE || '',
+    shop: process.env.MOLLIE_API_KEY_SHOP || '',
+    doneer: process.env.MOLLIE_API_KEY_DONEER || '',
 };
 
-export function unrollResult(result) {
+export function unrollResult(result: List<Payment>): Observable<Payment> {
     // log(result);
     // const { count, nextPage, links } = result;
     return concat(of(result), of(result.nextPage ? listAll(result.nextPage()) : []));
 }
 
-export function listAll(page$) {
+export function listAll(page$: Promise<List<Payment>>): Observable<Payment> {
     return from(page$).pipe(
         mergeMap(unrollResult)
     );

tests/airtable.test.ts

@@ -1,3 +1,4 @@
+import Airtable from 'airtable';
 import { tbl } from '../src/airtable';
 
 test('airtable can print records', () => {
@@ -7,7 +8,7 @@ test('airtable can print records', () => {
     // .eachPage()
     // .forEach()
     .then(records => {
-        records.forEach(record => {
+        records.forEach((record: Airtable.Record<any>) => {
             console.log(record.fields);
         });
     });

tests/mollie.test.ts

@@ -2,7 +2,7 @@ import { createMollieClient } from '@mollie/api-client';
 import { mollieKeys, listAll } from '../src/mollie';
 const log = console.log.bind(console);
 
-test('airtable can print records', (done) => {
+test('airtable can print records', (done: () => void) => {
     const mollieClient = createMollieClient({ apiKey: mollieKeys.leden });
     // const entity = mollieClient.customers;
     const entity = mollieClient.payments;
@@ -13,10 +13,10 @@ test('airtable can print records', (done) => {
     
     log('just before subscribe');
     obs.subscribe({
-      next(x) {
+      next(x: any) {
         log('got value ' + x);
       },
-      error(err) {
+      error(err: string) {
         console.error('something wrong occurred: ' + err);
       },
       complete() {