使用 Array.reduce() 按多个键对数组进行分组

Question

I am writing here for the first time, and I was given the following problem. For example, I have the following array:

const input = [
  {
    id: 1,
    date: "01-01-2021",
    source: "TT",
    metrics: { conversions: 10, cpl: 3 },
  },
  {
    id: 2,
    date: "01-01-2021",
    source: "TT",
    metrics: { conversions: 15, cpl: 3 },
  },
  {
    id: 3,
    date: "01-01-2021",
    source: "FB",
    metrics: { conversions: 15, cpl: 4 },
  },
  {
    id: 4,
    date: "01-01-2021",
    source: "FB",
    metrics: { conversions: 15, cpl: 4 },
  },
  {
    id: 5,
    date: "02-01-2021",
    source: "TT",
    metrics: { conversions: 5, cpl: 2 },
  },
  {
    id: 6,
    date: "02-01-2021",
    source: "TT",
    metrics: { conversions: 15, cpl: 2 },
  },
  {
    id: 7,
    date: "02-01-2021",
    source: "FB",
    metrics: { conversions: 25, cpl: 1 },
  },
  {
    id: 8,
    date: "02-01-2021",
    source: "FB",
    metrics: { conversions: 30, cpl: 1 },
  },
];

And I need to get an array grouped by date and source and the value will be the sum of all its values for a specific date, for example as the result below:

const output = [
  {
    date: "01-01-2021",
    TT: 25,
    FB: 30,
  },
  {
    date: "02-01-2021",
    TT: 20,
    FB: 55,
  },
];

In my solution, I find unique keys and dates, but do not understand what to do next. Can you help me? Sample code:

const result = input.reduce((acc, current) => {
  const dateItem = acc.find((item) => item.date === current.date);
  const sources = input.map((item) => item.source).filter((value, index, self) => self.indexOf(value) === index);

  if (dateItem) {
    return [...acc.filter((i) => i.date !== current.date), { ...dateItem }];
  }

  return [...acc, { date: current.date }];
}, []);

Answer 1

Simple reduce loop using the date as a key. After you get it all combined, you can use values to get the array.

 const input = [{ id: 1, date: "01-01-2021", source: "TT", metrics: { conversions: 10, cpl: 3 }, }, { id: 2, date: "01-01-2021", source: "TT", metrics: { conversions: 15, cpl: 3 }, }, { id: 3, date: "01-01-2021", source: "FB", metrics: { conversions: 15, cpl: 4 }, }, { id: 4, date: "01-01-2021", source: "FB", metrics: { conversions: 15, cpl: 4 }, }, { id: 5, date: "02-01-2021", source: "TT", metrics: { conversions: 5, cpl: 2 }, }, { id: 6, date: "02-01-2021", source: "TT", metrics: { conversions: 15, cpl: 2 }, }, { id: 7, date: "02-01-2021", source: "FB", metrics: { conversions: 25, cpl: 1 }, }, { id: 8, date: "02-01-2021", source: "FB", metrics: { conversions: 30, cpl: 1 }, }, ]; const results = Object.values(input.reduce((o, data) => { o[data.date] = o[data.date] || { date: data.date }; o[data.date][data.source] = (o[data.date][data.source] || 0) + data.metrics.conversions; return o; }, {})); console.log(results);

Answer 2

Array.reduce with Object.values will give the result.

 const input = [ { id: 1, date: "01-01-2021", source: "TT", metrics: { conversions: 10, cpl: 3 }, }, { id: 2, date: "01-01-2021", source: "TT", metrics: { conversions: 15, cpl: 3 }, }, { id: 3, date: "01-01-2021", source: "FB", metrics: { conversions: 15, cpl: 4 }, }, { id: 4, date: "01-01-2021", source: "FB", metrics: { conversions: 15, cpl: 4 }, }, { id: 5, date: "02-01-2021", source: "TT", metrics: { conversions: 5, cpl: 2 }, }, { id: 6, date: "02-01-2021", source: "TT", metrics: { conversions: 15, cpl: 2 }, }, { id: 7, date: "02-01-2021", source: "FB", metrics: { conversions: 25, cpl: 1 }, }, { id: 8, date: "02-01-2021", source: "FB", metrics: { conversions: 30, cpl: 1 }, }, ]; const output = input.reduce((acc, curr) => { if (acc[curr.date]) { acc[curr.date][curr.source] = (acc[curr.date][curr.source] || 0) + curr.metrics.conversions; } else { acc[curr.date] = { date: curr.date, [curr.source]: curr.metrics.conversions } } return acc; }, {}); console.log(Object.values(output));