cloki/plugins/unwrap_registry/derivative.js

LogQL API with Clickhouse Backend

const { PluginLoaderBase } = require('plugnplay')

module.exports = class extends PluginLoaderBase {
  exportSync (api) {
    return {
      derivative: {
        /**
                 *
                 * @param sum {any} previous value for the current time bucket
                 * @param val {{unwrapped: number}} current values
                 * @param time {number} timestamp in ms for the current value
                 * @returns {any}
                 */
        run: (sum, val, time) => {
          sum = sum || {}
          sum.first = sum && sum.first && time > sum.first.time
            ? sum.first
            : {
                time: time,
                val: val.unwrapped
              }
          sum.last = sum && sum.last && time < sum.last ? sum.last : { time: time, val: val.unwrapped }
          return sum
        },
        /**
                 * @param sum {any} sum of the time bucket you have created during "run"
                 * @returns {number}
                 */
        approx: (sum) => {
          return sum && sum.last && sum.first && sum.last.time > sum.first.time
            ? (sum.last.val - sum.first.val) / (sum.last.time - sum.first.time) * 1000
            : 0
        }
      }
    }
  }
}