added function to get an AWS security token using STS

test/aws.js

@@ -0,0 +1,40 @@
+const test = require('tape').test ;
+const config = require('config');
+const opts = config.get('redis');
+const logger = require('pino')({level: 'error'});
+process.on('unhandledRejection', (reason, p) => {
+  console.log('Unhandled Rejection at: Promise', p, 'reason:', reason);
+});
+
+const sleep = (ms) => new Promise((resolve) => setTimeout(resolve, ms));
+
+test('AWS - create and cache auth token', async(t) => {
+  const fn = require('..');
+  const {client, getAwsAuthToken} = fn(opts, logger);
+
+  if (!process.env.AWS_ACCESS_KEY_ID || !process.env.AWS_SECRET_ACCESS_KEY || !process.env.AWS_REGION) {
+      t.pass('skipping AWS auth token tests since no AWS credentials provided');
+      t.end();
+      client.quit();
+      return;
+  }
+  try {
+    let obj = await getAwsAuthToken(process.env.AWS_ACCESS_KEY_ID, process.env.AWS_SECRET_ACCESS_KEY, process.env.AWS_REGION);
+    console.log({obj}, 'received auth token from AWS');
+    t.ok(obj.sessionToken && !obj.servedFromCache, 'successfullY generated auth token from AWS');
+
+    await sleep(250);
+    obj = await getAwsAuthToken(process.env.AWS_ACCESS_KEY_ID, process.env.AWS_SECRET_ACCESS_KEY, process.env.AWS_REGION);
+    console.log({obj}, 'received auth token from AWS - second request');
+    t.ok(obj.sessionToken && obj.servedFromCache, 'successfully received access token from cache');
+ 
+    await client.flushall();
+    t.end();
+  }
+  catch (err) {
+    console.error(err);
+    t.end(err);
+  }
+  client.quit();
+});
+

test/index.js

@@ -1,4 +1,7 @@
 require('./docker_start');
 require('./synth');
 require('./list-voices');
+require('./aws');
+require('./ibm');
+require('./nuance');
 require('./docker_stop');