如何处理此JSON数组，以删除数组的每个元素中的包装器对象？ 使用JavaScript

Question

I am not so into JavaScript and I have the following problem.

I have a JSON document like this:

{
  "forecast": [
    {
      "day-1": {
        "forecast_date": "2017-11-23",
        "morning": {
          "weather": {
            "meteo_forecast_id": 19,
            "meteo_forecast_date_time": "2017-11-23 06:00:00",
            "meteo_forecast_description_id": 2,
            "min_temp": 26,
            "max_temp": 31,
            "meteo_forecast_description_name": "Light Rain",
            "meteo_forecast_description": "Light Rain",
            "meteo_forecast_description_audio_link": "audio_link.html",
            "icon_link": "Light_Rain.png"
          }
        },
        "afternoon": {
          "weather": {
            "meteo_forecast_id": 20,
            "meteo_forecast_date_time": "2017-11-23 12:00:00",
            "meteo_forecast_description_id": 1,
            "min_temp": 33,
            "max_temp": 27,
            "meteo_forecast_description_name": "Mostly Cloudy",
            "meteo_forecast_description": "Mostly Cloudy",
            "meteo_forecast_description_audio_link": "audio_link.html",
            "icon_link": "Mostly_Cloudy_Icon.png"
          }
        }
      }
    },
    {
      "day-2": {
        "forecast_date": "2017-11-24",
        "morning": {
          "weather": {
            "meteo_forecast_id": 22,
            "meteo_forecast_date_time": "2017-11-24 06:00:00",
            "meteo_forecast_description_id": 2,
            "min_temp": 30,
            "max_temp": 34,
            "meteo_forecast_description_name": "Light Rain",
            "meteo_forecast_description": "Light Rain",
            "meteo_forecast_description_audio_link": "audio_link.html",
            "icon_link": "Light_Rain.png"
          }
        },
        "afternoon": {
          "weather": {
            "meteo_forecast_id": 23,
            "meteo_forecast_date_time": "2017-11-24 12:00:00",
            "meteo_forecast_description_id": 2,
            "min_temp": 34,
            "max_temp": 31,
            "meteo_forecast_description_name": "Light Rain",
            "meteo_forecast_description": "Light Rain",
            "meteo_forecast_description_audio_link": "audio_link.html",
            "icon_link": "Light_Rain.png"
          }
        }
      }
    }
}

As you can see there is an array named forecast that contains some object {} which in turn contains a "day-X":{...} objet containing some other fields.

Ok, my problem is: I have to remove these day-X object and put the content directly inside the main {} object.

So, starting from the previous array I have to obtain something like this:

{
    "forecast": [
        {
            "forecast_date": "2017-11-23",
            "morning": {
                "weather": {
                    "meteo_forecast_id": 19,
                    "meteo_forecast_date_time": "2017-11-23 06:00:00",
                    "meteo_forecast_description_id": 2,
                    "min_temp": 26,
                    "max_temp": 31,
                    "meteo_forecast_description_name": "Light Rain",
                    "meteo_forecast_description": "Light Rain",
                    "meteo_forecast_description_audio_link": "audio_link.html",
                    "icon_link": "Light_Rain.png"
                }
            },
            "afternoon": {
                "weather": {
                    "meteo_forecast_id": 20,
                    "meteo_forecast_date_time": "2017-11-23 12:00:00",
                    "meteo_forecast_description_id": 1,
                    "min_temp": 33,
                    "max_temp": 27,
                    "meteo_forecast_description_name": "Mostly Cloudy",
                    "meteo_forecast_description": "Mostly Cloudy",
                    "meteo_forecast_description_audio_link": "audio_link.html",
                    "icon_link": "Mostly_Cloudy_Icon.png"
                }
            }
        },
        {
            "forecast_date": "2017-11-24",
            "morning": {
                "weather": {
                    "meteo_forecast_id": 22,
                    "meteo_forecast_date_time": "2017-11-24 06:00:00",
                    "meteo_forecast_description_id": 2,
                    "min_temp": 30,
                    "max_temp": 34,
                    "meteo_forecast_description_name": "Light Rain",
                    "meteo_forecast_description": "Light Rain",
                    "meteo_forecast_description_audio_link": "audio_link.html",
                    "icon_link": "Light_Rain.png"
                }
            },
            "afternoon": {
                "weather": {
                    "meteo_forecast_id": 23,
                    "meteo_forecast_date_time": "2017-11-24 12:00:00",
                    "meteo_forecast_description_id": 2,
                    "min_temp": 34,
                    "max_temp": 31,
                    "meteo_forecast_description_name": "Light Rain",
                    "meteo_forecast_description": "Light Rain",
                    "meteo_forecast_description_audio_link": "audio_link.html",
                    "icon_link": "Light_Rain.png"
                }
            }
        }
    ]
}

What is a smart way to do it? Starting from the original forecast array how can I delete the day-x wrapper objets and mantain theirs content into the {...} object elements of this array? I have to do it in pure JavaScript and I can't use third parts library or framework

Answer 1

Use map to iterate and return the first value using Object.values from every item in the array.

obj.forecast = obj.forecast.map( s => Object.values(s)[0] )

Demo

 var obj = { "forecast": [ { "day-1": { "forecast_date": "2017-11-23", "morning": { "weather": { "meteo_forecast_id": 19, "meteo_forecast_date_time": "2017-11-23 06:00:00", "meteo_forecast_description_id": 2, "min_temp": 26, "max_temp": 31, "meteo_forecast_description_name": "Light Rain", "meteo_forecast_description": "Light Rain", "meteo_forecast_description_audio_link": "audio_link.html", "icon_link": "Light_Rain.png" } }, "afternoon": { "weather": { "meteo_forecast_id": 20, "meteo_forecast_date_time": "2017-11-23 12:00:00", "meteo_forecast_description_id": 1, "min_temp": 33, "max_temp": 27, "meteo_forecast_description_name": "Mostly Cloudy", "meteo_forecast_description": "Mostly Cloudy", "meteo_forecast_description_audio_link": "audio_link.html", "icon_link": "Mostly_Cloudy_Icon.png" } } } }, { "day-2": { "forecast_date": "2017-11-24", "morning": { "weather": { "meteo_forecast_id": 22, "meteo_forecast_date_time": "2017-11-24 06:00:00", "meteo_forecast_description_id": 2, "min_temp": 30, "max_temp": 34, "meteo_forecast_description_name": "Light Rain", "meteo_forecast_description": "Light Rain", "meteo_forecast_description_audio_link": "audio_link.html", "icon_link": "Light_Rain.png" } }, "afternoon": { "weather": { "meteo_forecast_id": 23, "meteo_forecast_date_time": "2017-11-24 12:00:00", "meteo_forecast_description_id": 2, "min_temp": 34, "max_temp": 31, "meteo_forecast_description_name": "Light Rain", "meteo_forecast_description": "Light Rain", "meteo_forecast_description_audio_link": "audio_link.html", "icon_link": "Light_Rain.png" } } } } ] }; obj.forecast = obj.forecast.map( s => Object.values(s)[0] ); console.log( obj ); 

Answer 2

Assuming you need to read the file first:

const fs = require('fs');

fs.readFile('/path/to/file.json', (err, file) => {
  const document = JSON.parse(file);
  document.forecast = document.forecast.map((days) => {
    return Object.keys(days).reduce((day, key) => days[key], {});
  });
  // console.log(document) or do what you want.
}

The Object.values() answer someone else provided should also work instead of my Object.keys() reduction here, but note that Object.values() has much less support as it's a much newer method.