If you have binary data that you need to encode to pass to the client as JSON, you can convert it to base64, a common means on the Internet to represent eight-bit values in solely printable characters. Node.js provides the Buffer object and a base64 encoder and decoder for this task.
First, you'll allocate a buffer, and then you'll convert it to a string, indicating that the string you want should be base64-encoded, like this:
var buffer = newBuffer('Hello world');
var string = buffer.toString('base64');The Node.js Buffer class wraps a collection of octets outside the Node.js V8 runtime heap. It's used in Node.js anytime you need to work with purely binary data. The first line of our example makes a buffer, populating it with the string Hello world.
The Buffer class includes the toString method, which takes a single argument, the means to encode the buffer. Here, we're passing base64, indicating that we want s to...