javascript - 如何根据对象中的属性合并对象数组中的对象

Question

我有一系列事件，例如

this.activities = [
{
id: 54,
event_type: 'CA',
user_id: 56,
user_name: 'Anand',
purpose: disregard,
timestamp: 14356787
},
{
id: 54,
event_type: 'NA',
user_id: 56,
user_name: 'Anand',
purpose: 'privacy',
timestamp: ''
},
{
id: 54,
event_type: 'FA',
user_id: 56,
user_name: 'Anand',
purpose: 'Call',
timestamp: ''
},
{
id: 54,
event_type: 'FA',
user_id: 56,
user_name: 'Anand',
purpose: 'Listen',
timestamp: ''
},
{
id: 54,
event_type: 'CA',
user_id: 56,
user_name: 'Anand',
purpose: 'Not allowed',
timestamp: 14356784
},
{
id: 54,
event_type: 'NA',
user_id: 56,
user_name: 'Anand',
purpose: 'data',
timestamp: 14356786
},
{
id: 54,
event_type: 'CA',
user_id: 56,
user_name: 'Anand',
purpose: 'voicemail',
timestamp: 14356785
},
{
id: 54,
event_type: 'CA',
user_id: 56,
user_name: 'Anand',
purpose: 'phone',
timestamp: 14356775
},
{
id: 54,
event_type: 'CA',
user_id: 56,
user_name: 'Anand',
purpose: 'email',
timestamp: 14356776
},
{
id: 54,
event_type: 'CA',
user_id: 56,
user_name: 'Anand',
purpose: 'letter',
timestamp: 14356777
}
]

我只想根据每个事件的 5ms 时间戳差异，仅按 event_type“CA”对该数组进行分组/过滤。因此，如果 event_type 'CA' 的事件的时间戳彼此相差 5 毫秒以内，则将这些事件组合起来，并形成一个新的事件，除了名为 CA_combined 的组合事件的新 event_type 之外，所有内容都相同。所以这个数组应该像这样

this.activities = [
{
id: 54,
event_type: 'CA_combined',
user_id: 56,
user_name: 'Anand',
purposes: ['disregard', 'Not allowed', 'voicemail'],
timestamp: 14356787
},
{
id: 54,
event_type: 'CA_combined',
user_id: 56,
user_name: 'Anand',
purposes: ['letter','email','phone']
timestamp: 14356777
},
{
id: 54,
event_type: 'NA',
user_id: 56,
user_name: 'Anand',
purpose: 'privacy',
timestamp: ''
},
{
id: 54,
event_type: 'FA',
user_id: 56,
user_name: 'Anand',
purpose: 'Call',
timestamp: ''
},
{
id: 54,
event_type: 'FA',
user_id: 56,
user_name: 'Anand',
purpose: 'Listen',
timestamp: ''
},
{
id: 54,
event_type: 'NA',
user_id: 56,
user_name: 'Anand',
purpose: 'data',
timestamp: 14356786
}
]

我该如何实现这样的目标？我现在的尝试，过滤所有 event_type 为 CA 的事件，并根据时间戳值对数组进行排序

let consentActivities = this.activities.filter(c => {
        if (c.event_type === 'CA') {
          return true
        } else {
          return false
        }
      })
consentActivities.sort((a, b) => {
        return b.timestamp - a.timestamp
      })

这就是我不知道如何在 5 毫秒内对事件进行分组并完全失去它的地方

 if (consentActivities.length && consentActivities[0].timestamp - consentActivities[consentActivities.length - 1].timestamp <= 5) {
        consentActivities[0].purposes = []
        consentActivities.forEach((p) => {
          consentActivities[0].purposes.push(p.purpose)
        })
        // consentActivities.splice(1, consentActivities.length)
      }

任何意见都将受到高度赞赏

Answer 1

您已经采取了正确的第一步:过滤掉 CA，进行排序，然后您可以通过访问之前的索引轻松进行分组:

  const entries = data
    .filter(it => it.event_type === "CA")
    .sort((a, b) => a.timestamp - b.timestamp);

 const grouped = [];

 for(const entry of entries) {
   const previous = grouped[grouped.length - 1];
   if(previous && Math.abs(entry.timestamp - previous.timestamp) < 5) {
      previous.purposes.push(entry.purpose);
   } else {
     grouped.push({ id: entry.id, /*...*/, purposes: [entry.purpose] });
   }
}