Often it doesn’t matter when a Promise returns data and the members of a collection of Promises can be resolved independently without regard to timing. A function can perform asynchronous tasks that don’t depend on the data from, or the success of, other asynchronous tasks.
But sometimes business rules or program design require that asynchronous actions are dependent on other asynchronous operations. For example...
Are you a developer looking for a new hobby that’s compatible with sheltering in place? Would you like to be able to share it with friends from a virus-safe distance?
You can stargaze from the safety of your own lawn, balcony, or roof, and you don’t need any equipment other than your own eyes, and maybe a pair of binoculars. There are plenty of bright objects in the night sky that are visible with the naked eye. One of them is the International Space Station (ISS), which is the third brightest object in the sky after the sun and moon.
The ISS whips around the earth at 27,576 kilometers per hour (17,000 miles per hour), making a complete orbit every 94 minutes. Opportunities to observe it only last a few minutes, so it’s helpful to know when the ISS will be visible and from which direction it will appear.
SMS messages can reach over 4.5 billion text-enabled devices to notify people about upcoming appointments, emergencies, traffic disruptions, or commercial promotions. Sending SMS messages programmatically enables you to reach many people almost simultaneously. With Twilio Programmable SMS you can create a Node.js application that sends many messages and reports when each of them has been delivered—or not.
You can create a mechanism for monitoring and reporting the status...