Flatten array with multiple nested objects

Question

I have an array like this and I want it to be flatted in order to generate an excel with it, but I can't get more than two levels of flat. This is my data:

[
   {
      "idClient":1,
      "clientName":"Client One",
      "numItems":72,
      "projects":[
         {
            "idProject":1,
            "projectName":"Project One",
            "numItems":72,
            "languages":[
               {
                  "sourceLanguage":26,
                  "sourceLanguageName":"Spanish",
                  "numItems":72,
                  "targets":[
                     {
                        "targetLanguage":74,
                        "targetLanguageName":"English",
                        "numItems":36,
                        "numItemsSold":30,
                     },
                     {
                        "targetLanguage":20,
                        "targetLanguageName":"French",
                        "numItems":36,
                        "numItemsSold":7,
                     }
                  ]
               }
            ]
         }
      ]
   },
      {
      "idClient":1,
      "clientName":"Client One",
      "numItems":50,
      "projects":[
         {
            "idProject":1,
            "projectName":"Project Two",
            "numItems":50,
            "languages":[
               {
                  "sourceLanguage":26,
                  "sourceLanguageName":"Spanish",
                  "numItems":50,
                  "targets":[
                     {
                        "targetLanguage":74,
                        "targetLanguageName":"English",
                        "numItems":30,
                        "numItemsSold":3,
                     },
                     {
                        "targetLanguage":20,
                        "targetLanguageName":"French",
                        "numItems":20,
                        "numItemsSold":7,
                     }
                  ]
               }
            ]
         }
      ]
   }
]

What I want is generate a simple string list, with one row per target, something similar to this:

[
  {"Client One", "Proyect One", "Spanish", "English", "36", "30" },
  {"Client One", "Proyect One", "Spanish", "French", "36", "7" },
  {"Client One", "Proyect Two", "Spanish", "English", "30", "3" },
  {"Client One", "Proyect Two", "Spanish", "English", "20", "7" },
]

Looking on the internet and on stackoverflow, I found some interesting functions, like this one, but i cannot go beyond the languages property:

const fn = arr =>
          arr.flatMap(({ projects, ...rest }) =>
            projects.map(o => ({
              ...rest,
              ...o,
            }))
          );

Any help would be apprecited. Thanks in advace

Answer 1

I think you will have to flatMap all the arrays above targets, like this:

let data = [
   {
      "idClient":1,
      "clientName":"Client One",
      "numItems":72,
      "projects":[
         {
            "idProject":1,
            "projectName":"Project One",
            "numItems":72,
            "languages":[
               {
                  "sourceLanguage":26,
                  "sourceLanguageName":"Spanish",
                  "numItems":72,
                  "targets":[
                     {
                        "targetLanguage":74,
                        "targetLanguageName":"English",
                        "numItems":36,
                        "numItemsSold":30,
                     },
                     {
                        "targetLanguage":20,
                        "targetLanguageName":"French",
                        "numItems":36,
                        "numItemsSold":7,
                     }
                  ]
               }
            ]
         }
      ]
   },
      {
      "idClient":1,
      "clientName":"Client One",
      "numItems":50,
      "projects":[
         {
            "idProject":1,
            "projectName":"Project Two",
            "numItems":50,
            "languages":[
               {
                  "sourceLanguage":26,
                  "sourceLanguageName":"Spanish",
                  "numItems":50,
                  "targets":[
                     {
                        "targetLanguage":74,
                        "targetLanguageName":"English",
                        "numItems":30,
                        "numItemsSold":3,
                     },
                     {
                        "targetLanguage":20,
                        "targetLanguageName":"French",
                        "numItems":20,
                        "numItemsSold":7,
                     }
                  ]
               }
            ]
         }
      ]
   }
]

const fn = arr =>
          arr.flatMap(({ projects, ...rest }) =>
            projects.flatMap(({languages, ...rest1}) => 
              languages.flatMap(({targets, ...rest2}) => {
                return targets.map(t => ({...t, ...rest, ...rest1, ...rest2}))
              })
            )
          );
          
data = fn(data);
console.log(data);

This will give you flattened key-value pairs.