Calling a function after another function is done making changes to a Google Sheet

Question

I'm using this solution to post an online survey's entries into a Google Spreadsheet:

https://gist.github.com/hamx0r/b851531d8546565c23deab926ee6867e

/*   
   Copyright 2011 Martin Hawksey
   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at
       http://www.apache.org/licenses/LICENSE-2.0
   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
*/

// Usage
//  1. Enter sheet name where data is to be written below
        var SHEET_NAME = "Sheet1";

//  2. Run > setup
//
//  3. Publish > Deploy as web app 
//    - enter Project Version name and click 'Save New Version' 
//    - set security level and enable service (most likely execute as 'me' and access 'anyone, even anonymously) 
//
//  4. Copy the 'Current web app URL' and post this in your form/script action 
//
//  5. Insert column names on your destination sheet matching the parameter names of the data you are passing in (exactly matching case)

var SCRIPT_PROP = PropertiesService.getScriptProperties(); // new property service

// If you don't want to expose either GET or POST methods you can comment out the appropriate function
function doGet(e){
  return handleResponse(e);
}

function doPost(e){
  return handleResponse(e);
}

function handleResponse(e) {
  // shortly after my original solution Google announced the LockService[1]
  // this prevents concurrent access overwritting data
  // [1] http://googleappsdeveloper.blogspot.co.uk/2011/10/concurrency-and-google-apps-script.html
  // we want a public lock, one that locks for all invocations
  var lock = LockService.getPublicLock();
  lock.waitLock(30000);  // wait 30 seconds before conceding defeat.

  try {
    // next set where we write the data - you could write to multiple/alternate destinations
    var doc = SpreadsheetApp.openById(SCRIPT_PROP.getProperty("key"));
    var sheet = doc.getSheetByName(SHEET_NAME);

    // we'll assume header is in row 1 but you can override with header_row in GET/POST data
    var headRow = e.parameter.header_row || 1;
    var headers = sheet.getRange(headRow, 1, 1, sheet.getLastColumn()).getValues()[0];
    var nextRow = sheet.getLastRow()+1; // get next row
    var row = []; 
    // loop through the header columns
    for (i in headers){
      if (headers[i] == "Timestamp"){ // special case if you include a 'Timestamp' column
        row.push(new Date());
      } else { // else use header name to get data
        row.push(e.parameter[headers[i]]);
      }
    }
    // more efficient to set values as [][] array than individually
    sheet.getRange(nextRow, 1, 1, row.length).setValues([row]);
    // return json success results
    return ContentService
          .createTextOutput(JSON.stringify({"result":"success", "row": nextRow}))
          .setMimeType(ContentService.MimeType.JSON);
  } catch(e){
    // if error return this
    return ContentService
          .createTextOutput(JSON.stringify({"result":"error", "error": e}))
          .setMimeType(ContentService.MimeType.JSON);
  } finally { //release lock
    lock.releaseLock();
  }
}

function setup() {
    var doc = SpreadsheetApp.getActiveSpreadsheet();
    SCRIPT_PROP.setProperty("key", doc.getId());
}

Except, when users omit to fill a field on the survey page, the corresponding cell appears blank in google Sheets. This is quite normal and intuitive, but for what I want to do afterwards, I need blank cells to instead appear as the string "...".

So I wrote this (with big help from another answer):

function fillBlanks() {
  var ss = SpreadsheetApp.getActiveSpreadsheet();
    var sheet = ss.getSheets()[0];
    var range = sheet.getRange("A:W");


        var last_row=sheet.getLastRow();
        var data=sheet.getRange(1,1,last_row,23).getValues();

        for (var i = 1; i < last_row + 1; i++) {
            for(var y = 1; y < 23 ; y++){
              var cell = range.getCell(i, y);
              if (cell.isBlank()) {
                cell.setValue("...");
              }

            }
        }   
}

This function is in another file, as such:

Now, I need fillBlanks() to be called every time the first script takes Post from the survey page, and insert a row. That is, I need this function to be called after the changes have been done. And I cannot find the proper way to do so.

I tried inserting "fillBlanks();" at the end of the handleResponse function, with no success...

Where and how should I call fillBlanks() to make this happen?

Answer 1

From your script, when doGet() is run, it seems that you put e.parameter with the key of headers[i] at row.push(e.parameter[headers[i]]);. At this time, if you don't want to put the blank when the values were given to doGet(e), how about this modification?

From :

row.push(e.parameter[headers[i]]);

To :

var v = e.parameter[headers[i]];
row.push(v || "...");

Note :

• At this modified script, when there is no e.parameter[headers[i]], ... is put.
• Then, if you use fillBlanks(), when the spreadsheet is used by Web Apps, the file ID is required to be directly used. So it is required to be modified from var ss = SpreadsheetApp.getActiveSpreadsheet(); to var ss = SpreadsheetApp.openById("### fileId ###");.

If my understanding was not correct, I'm sorry.