Task Tutorial

task()

The main function of the task is to submit "Hello, World!" to K2.

Update task() with the code block below to fulfill the task's logic:

async task() {
    try {
      const value = "Hello, World!";

      if (value) {
        // store value on NeDB
        await namespaceWrapper.storeSet("value", value);
      }
    } catch (err) {
      console.log("ERROR IN EXECUTING TASK", err);
    }
}

fetchSubmission()

The fetchSubmission method will fetch and return the submission value from NeDB using the namespaceWrapper.storeGet() method.

Update fetchSubmission() with the code block below:

async fetchSubmission() {
    const value = await namespaceWrapper.storeGet("value"); // retrieves the value
    console.log("VALUE", value);
    return value;
}

submitTask()

The submitTask method calls fetchSubmission() to retrieve the submission value from NeDB and submits it to K2 along with the current roundNumber.

async submitTask(roundNumber) {
    try {
      const submission = await this.fetchSubmission();
      console.log("SUBMISSION", submission);
      await namespaceWrapper.checkSubmissionAndUpdateRound(
        submission,
        roundNumber,
      );
    } catch (error) {
      console.log("error in submission", error);
    }
}

validateNode()

This method verifies that a node submitted the correct value, "Hello, World!" This method returns true if the value is correct, otherwise false.

Update validateNode() with the code block below:

async validateNode(submission_value, round) {
    let vote;
    console.log("SUBMISSION VALUE", submission_value, round);

    try {
      if (submission_value == "Hello, World!") {
        vote = true;
      } else {
        vote = false;
      }
    } catch (e) {
      console.error(e);
      vote = false;
    }

    return vote;
}

generateDistributionList()

The Task Template contains a sample logic for the generateDistributionList(), which rewards 1 KOII to all the nodes with valid submissions for that round. We'd retain the logic for the Hello World project.

In the sample code:

• An empty distribution list is initialized
• The task's data is retrieved using the getTaskState helper function
• All submissions are fetched from the task's data
• The submissions_audit_trigger is also retrieved from the task's data; this object contains information about the audited submissions
• An empty distribution list is returned if submissions is null. Otherwise, the keys and values of submissions are grouped separately, and in a loop, it calculates the audits on each submission and the number of votes on the audit and then generates a distribution list based on that.

validateDistribution()

In the sample code present in the template:

• The distribution list is fetched
• If the distribution list is not null, it is parsed and stored in the variable fetchedDistributionList
• The distribution list is re-generated by calling the generateDistributionList method with the current round number and task state as parameters
• The generated distribution list is stored in the variable generatedDistributionList
• Finally, fetchedDistributionList and generatedDistributionList are compared to see if they are equal. If they are, this method returns true, otherwise false.

info

When creating a task using the Task Template, there's usually no need to edit the following methods: auditTask(), auditDistribution(), and submitDistributionList().