Node's createHmac function

Question

for the node.js crypto command:

crypto.createHmac('this is a test', key);

What is node expecting for key's encoding?

utf8? a binary buffer?

Answer 1

Since javascript uses UTF-16 strings, I suspect it is expecting a UTF-16 encoded string. Just to clarify, your first parameter should be a hash algorithm ('sha1', 'md5', etc.) not the data to be encrypted.

Answer 2

First parameter should be the algorythm, not the input to be HMACed, should be one of the following -

MD5
SHA
SHA1
SHA256
SHA384

The key is a secret / salt string.

crypto.createHmac returns a stream, you write your input into it and once you start reading, it returns the computed digests.