Trackers

Trackers track the value(s) of something. Anything, really. A tracker does this every hour or every day. Once a tracker tracks an event, it sends it to our databases to be saved for up to a month.

Trackers are used to easily show statistics without having to manage the data yourself.

Example

const kontrl = require("kontrl");

// This tracker counts the rows of the users table (see tables documentation)
const myUserTracker = kontrl.tracker.countResources({
  resourceNames: ["users"],
  precision: "hour" // Can be once an hour or once a day.
});

There are a few premade trackers. It’s also possible to make your own trackers.

Premade trackers

• events Uses custom events to make a graph (see Events documentation).
• countResource Tracks how many items there are in a table
• custom trackers See the “Custom trackers” section.

Events tracker

When you throw events, (see Events page), you can make a tracker to display this data on the dashboard.

Params:

• eventName the name of the events. (see Events page).

const kontrl = require("kontrl");

const routeVisitsTracker = kontrl.tracker.events({
  eventName: "route_visits"
});

Count Resources tracking

A simple premade tracker the items of 1 or more tables. (see Tables page).

Params:

• resourceNames an array of 1 or more table names.
• precision how often you want to track. can be “hour” or “day”.

const kontrl = require("kontrl");

const userCountTracker = kontrl.tracker.countResources({
  resourceNames: ["users"],
  precision: "hour"
})

Custom trackers

It’s incredibly easy to write your own trackers.

First, decide whether you want to track a single number or multiple numbers at the same time.

Tracking a single value

You track a single value by using the kontrl.tracker.single(..) function.

Params:

• uniqueName the name of what are tracking. Unique within your application and maximum 20 characters long.
• precision the interval at which the value will get tracked. Can be “hour” or “day” meaning hourly and daily respectively.
• getValue the function which will be called every hour or day that gets the value. This function expects a single number as a return

const kontr = require("kontrl");

kontrl.tracker.single({
  uniqueName: "new_users_today",
  precision: "day",
  getValue() {
    const newUserCount = 100; // get the data from your database
    return newUserCount;
  }
})

Tracking multiple values

You track a combination of values using the kontrl.tracker.many(..) function.

Params:

• uniqueName the name of what are tracking. Unique within your application and maximum 20 characters long.
• precision the interval at which the value will get tracked. Can be “hour” or “day” meaning hourly and daily respectively.
• getValue the function that gets the value. This function returns an object.

const kontr = require("kontrl");

kontrl.tracker.many({
  uniqueName: "stock",
  precision: "day",
  getValues() {
    // Get the current stock items
    const itemsInStock = { "gameboy": 3, "Pokemon fire red": 9 };
    return itemsInStock;
  }
})