按 Apps 脚本中的列名读取 Google Sheet Exported JSON

Question

I'm exploring the use of JSON exported Google Sheets as database for Apps Script.

The fetched url follows the structure: https://docs.google.com/spreadsheets/d/DOCUMENTID/gviz/tq?tqx=out:json&gid=SHEETID

JSON.json

{
    "reqId": "0",
    "sig": "000",
    "status": "ok",
    "table": {
        "cols": [
            {
                "id": "A",
                "label": "",
                "type": "string"
            },
            {
                "id": "B",
                "label": "",
                "type": "string"
            },
            {
                "id": "C",
                "label": "",
                "type": "string"
            }
        ],
        "parsedNumHeaders": 0,
        "rows": [
            {
                "c": [
                    {
                        "v": "Data 1-1"
                    },
                    {
                        "v": "Data 1-2"
                    },
                    {
                        "v": "Data 1-3"
                    }
                ]
            },
            {
                "c": [
                    {
                        "v": "Data 2-1"
                    },
                    {
                        "v": "Data 2-2"
                    },
                    {
                        "v": "Data 2-3"
                    }
                ]
            },
            {
                "c": [
                    {
                        "v": "Emails"
                    },
                    {
                        "v": "Ids"
                    },
                    {
                        "v": "Names"
                    }
                ]
            }
        ]
    },
    "version": "0.6"
}

In this function I'm getting returned an array of values for the C column: dataArray = [Data 1-3, Data 2-3]

function getRolePermission(databaseUrl) {

  let databaseParsed = JSON.parse(UrlFetchApp.fetch(databaseUrl).getContentText().match(/(?<=.*\().*(?=\);)/s)[0]);
  let tableLength = Object.keys(databaseParsed.table.rows).length;

  let dataArray = [];
  for (let i = 0; i < tableLength; i++) {
    dataArray.push(databaseParsed.table.rows[i].c[2].v)
  }

  return dataArray;

}

It works well, but I don't know how to make this function more generic, so I call it with (url, headerName) arguments to get an array with the values of a column. Something like:

function getRolePermission(databaseUrl, headerName) {
  // CODE ??
  return dataArray;
}

getRolePermission('https://docs.google.com/spreadsheets/d/1lc...', 'Emails')

to get dataArray = [Data 1-3, Data 2-3] , so if I change the order of columns I'm still getting the same results.

Answer 1

dataArray.push(databaseParsed.table.rows[i].c[2].v)

You just need to find the index 2 here to make the function more generic. The table.cols should give you the column headers, but it is not doing that because parsedNumHeaders is 0 in your case. To manually set number of headers, use &headers=1 . The url should look like:

https://docs.google.com/spreadsheets/d/DOCUMENTID/gviz/tq?tqx=out:json&gid=SHEETID&headers=1

The response then would look like:

{
  "reqId": "0",
  "sig": "000",
  "status": "ok",
  "table": {
    "cols": [
      {
        "id": "A",
        "label": "Names",
        "type": "string"
      },
      {
        "id": "B",
        "label": "Ids",
        "type": "string"
      },
      {
        "id": "C",
        "label": "Emails",
        "type": "string"
      }
    ],
    "parsedNumHeaders": 1,
    "rows": [
      {
        "c": [
          {
            "v": "Data 1-1"
          },
          {
            "v": "Data 1-2"
          },
          {
            "v": "Data 1-3"
          }
        ]
      },
      {
        "c": [
          {
            "v": "Data 2-1"
          },
          {
            "v": "Data 2-2"
          },
          {
            "v": "Data 2-3"
          }
        ]
      }
    ]
  },
  "version": "0.6"
}

Once you get the headers, you can find the index:

const columnNeeded = databaseParsed.table.cols.findIndex(obj => obj.label === headerName/*"Emails"*/);

Then, use it in your function

dataArray.push(databaseParsed.table.rows[i].c[columnNeeded].v)