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Task Functions


The task function contains the core logic of a Koii task, so when developing a new task, the logic for the main work to be performed by nodes will be written here. The proof of work done, which is usually a CID or hash, will be stored on NeDB.

The core logic for the sample task on the template is straightforward: a random number is generated, then it is converted to a string, and then a hash (or CID). The hash is a node's result, sent to K2 for auditing.

* @description Contains the logic to do the work required
* for submitting the values and optionally storing the result on levelDB
async function task() {
const x = Math.random().toString(); // generate random number and convert to string
const cid = crypto.createHash("sha1").update(x).digest("hex"); // convert to CID
console.log("HASH:", cid);

if (cid) {
await namespaceWrapper.storeSet("cid", cid); // store CID on levelDB


The fetchSubmission function retrieves a node's submission value(CID) from levelDB.

* @description Fetch's submission from levelDB
* @returns {string} The CID
async function fetchSubmission() {
const cid = await namespaceWrapper.storeGet("cid"); // retrieves the cid
return cid;


The submitTask function calls the fetchSubmission function to retrieve the CID and submits it to K2. To submit results on-chain, it calls the checkSubmissionAndUpdateRound helper function from namespace and adds the CID and current round number as parameters.

* @description Submits a node's result to K2
* @param {number} roundNumber Current round number of the task
async function submitTask(roundNumber) {
console.log("submitTask called with round", roundNumber);
try {
const cid = await fetchSubmission(); // retrieve CID
await namespaceWrapper.checkSubmissionAndUpdateRound(cid, roundNumber); // submit to K2
console.log("after the submission call");
} catch (error) {
console.log("error in submission", error);

After the off-chain work is completed and the results are submitted on-chain. The following window is for reviewing the submitted results.

In the following section, we will learn about audit functions.