javascript - 以 5 分钟间隔对数组进行排序，并具有唯一值计数

Question

我正在尝试以这样的方式对数组进行排序，以便获取从当天开始的 0:00 开始的 5 分钟间隔内唯一用户的计数。 如何定义纪元时间中的 5 分钟间隔？ (使用的数据将是当天的纪元)以及如何获取该时间间隔的唯一用户计数？

输入

[1486428994000, "user a"]    

[1486429834000, "user a"]

[1486429839000, "user a"]

[1486429869000, "user b"]

所需输出

[1486428900000, 1 ]

[1486429800000, 2 ]

Answer 1

// Remove doublons from an array.
const uniq = array =>
  array.filter((value, index) => array.indexOf(value) === index);

// Your function.
const groupCount = (data, timeWindow) =>
  data
    .reduce((groups, line) => {
      const current = groups[groups.length - 1];
      // If the line is outside of the current time window, push a new group.
      if (!current || line[0] > current[0] + timeWindow) {
        // Find the beginning of the corresponding time window.
        const windowStart = line[0] - line[0] % timeWindow;
        // Push the new group.
        groups.push([windowStart, [line[1]]]);
      } else {
        // Else add a new user to the group.
        current[1].push(line[1]);
      }
      return groups;
    }, [])
    // Once we created the groups, we remove doublons from them and count users.
    .map(group => [group[0], uniq(group[1]).length]);

const data = [
  [1486428994000, "user a"],
  [1486429834000, "user a"],
  [1486429839000, "user a"],
  [1486429869000, "user b"]
];
console.log(groupCount(data, 5 * 60 * 1000));