Google Apps Script - Convert cell to SHA256 within an Array Formula

Question

I have a simple script written to hash a cell, however it doesn't work within and array formula, and I am having a hard time figure out how to add that functionality.

 function SHA256 (input) { var rawHash = Utilities.computeDigest(Utilities.DigestAlgorithm.SHA_256, input); var txtHash = ''; for (i = 0; i < rawHash.length; i++) { var hashVal = rawHash[i]; if (hashVal < 0) { hashVal += 256; } if (hashVal.toString(16).length == 1) { txtHash += '0'; } txtHash += hashVal.toString(16); } return txtHash; }

Within Google Sheets, the above script allows me to hash using SHA526(A2)

I would like to be able to hash an entire column by using SHA256() within an array formula. =ArrayFormula(SHA256(A2:A))

The error I get is

"Exception: The parameters (DigestAlgorithm,number[]) don't match the method signature for Utilities.computeDigest. (line 2)."

Any direction would be greatly appreciated!

Answer 1

Google Apps Script - Custom Functions Documentation

In order to use an array you need to map the input. Using a simple else if you can test if the input is an array or a single value.

 function SHA256 (input) { if(input.map) { return input.map(SHA256); } else { var rawHash = Utilities.computeDigest(Utilities.DigestAlgorithm.SHA_256, input); var txtHash = ''; for (i = 0; i < rawHash.length; i++) { var hashVal = rawHash[i]; if (hashVal < 0) { hashVal += 256; } if (hashVal.toString(16).length == 1) { txtHash += '0'; } txtHash += hashVal.toString(16); } return txtHash; } }