NC | generate_entropy Using lsblk Command When No Candidates Were Found

[shirady]

Explain the changes

1. In case there was not disk found according to the hard-coded array of disk names, we will call the lsblk command and rerun the the same steps as before.
2. Refactoring:

• Change the condition if (entropy_avail < 512) to if (entropy_avail >= 512) return; to avoid additional nested layer.
• Separate functions.
• Add JSDoc to the new separated functions.

Issues: Fixed #8598

1. Currently there is an array of hard-coded disk names. In PR NC | Related to Issue 8598 | generate_entropy() - Add Disks (Temporary and Partial Fix) #8734 we added a partial solution and added 2 disk names to the array. Still, it is not enough as there might be a disk that was not in the array, and there might be a situation where the NVMe disk changes its namespace (from 1 to 2 for example), and then it is not in the array of the disk names (we have /dev/nvme0n1).

Testing Instructions:

Manual Test

1. Create a script copy the function that we created and run it on a GPFS machine, with the following changes:

• Add the following modules:

const util = require('util');
const fs = require('fs');
const child_process = require('child_process');
const async_exec = util.promisify(child_process.exec);
const chance = require('chance')();

const async_delay = util.promisify(setTimeout);

• Add the following main:

async function main() {
    console.log('SDSD in main');
    let still_reading = true;
    const promise = generate_entropy(() => still_reading);
}

• Call the main in the end of the script

exports.main = main;
if (require.main === module) main();

• Add the while (loop_cond()) { to comment to run it once.

• (first run) Add the script in the path: /usr/local/noobaa-core/ and run it with: node <path to the script>

• (secodn run) Change the condition (first appearance) if (disk_details.disk_size) { to if (false) { so we will get to the "else" clause we created, and rerun the script: node <path to the script>

• Doc added/updated

• Tests added

[shirady]

Updates:

• Currently, I'm waiting for an answer as to whether adding all the disk names is fine.
• If it is not, I would filter the array of disk names I get according to what I will be required to (from what I have in mind now - filter the array by names that start with "nvme").
• I will share that I plan to merge it for version 4.18.1.