Posted on

Uploading and Downloading Files: Streaming in Node.js

While the buffer APIs are easier to use to upload and download files, the streaming APIs are a great way to better manage memory and concurrency. In this post, you'll learn how to stream files between clients, Node.js, and Oracle Database.

Overview

The streaming APIs in Node.js are designed to leverage and simplify its evented nature. There are four different stream classes: Readable, Writeable, Transform, and Duplex. Readable streams (which includes Transform and Duplex) have a method that can be thought of like the pipe command in Linux, where the standard output of one command can be piped into the standard input of another command. Here's a command line example that takes the output from the ls (list) command and pipes it through the grep (search) command to show files that have the word "oracle" in the name:

Posted on

How to Interact With a Database Using Async Functions in Node.js

So far in this async series, we’ve covered Node.js style callbacks, the Async module, and promises. In this final part of the series, we’ll learn about async functions (AKA async/await). To me, async functions are the most exciting thing to happen to JavaScript since Ajax. Finally, we can read JavaScript code in a synchronous manner while it executes asynchronously as it always has.

Async Functions Overview

Async functions are a relatively new feature of JavaScript (not specific to Node.js). Support for the feature first landed in Node.js v7.6 via an update to the V8 JavaScript engine. Because async functions rely heavily on Promises, I recommend you read the previous post before continuing.