Apps Script to import Facebook Messages (JSON format) into a spreadsheet

Code.js

// 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
//
//     https://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.


/** @const {string} Id of the Drive folder with the Facebook data.
 *
 * You should get it from the URL:
 * https://drive.google.com/drive/folders/<DRIVE_FOLDER_ID>
 */
const DRIVE_FOLDER_ID = '';

/** @const {string} Id of the spreadsheet where to add the data.
 *
 * You should get it from the URL:
 * https://docs.google.com/spreadsheets/d/<SPREADSHEET_ID>/edit#gid=0
 */
const SPREADSHEET_ID = '';

/** @const {number} Number of messages to import. */
const MESSAGES_TO_LOG = 1; // Set to 0 to import all messages.

/** @{!Set<string>} Sender names to exclude.
 *
 * Normally it would be yours if you want to import only other people's
 * messages.
 */
const IGNORE_NAMES = new Set([
  'Your Name',
]);


/**
 * Iterates a folder to find all files, and import Facebook messages into
 * a spreadsheet. Folder is defined by DRIVE_FOLDER_ID and the spreadsheet
 * by SPREADSHEET_ID.
 *
 * Functions are put on a closure to avoid the function names from appearing on
 * the run menu. This makes it easier for users to know which function to run.
 */
const _importFacebookMessages = (() => {

  const spreadsheet = SpreadsheetApp.openById(SPREADSHEET_ID);
  if (!spreadsheet) throw new Error(`Spreadsheet ${SPREADSHEET_ID} not found.`);

  const sheets = spreadsheet.getSheets();
  const sheet = sheets[0];

  if (!sheet) {
    throw new Error(`No sheets found within spreadsheet ${SPREADSHEET_ID}.`);
  }

  /**
   * Adds messages into the sheet.
   * @param {!Array<string>} message to append. Each element is a cell.
   */
  const appendMessage = (message) => {
    console.log('Adding message row', message);
    sheet.appendRow(message);
  }

  /**
   * Processes message data following rules and imports into the sheet.
   * @param {!Array<!Object> messages in Facebook JSON format to import.
   */
  const importMessages = (messages) => {
    let mCounter = 0;
    for (let i = messages.length - 1; i >= 0; i--) {
      const message = messages[i];

      const senderName = message?.sender_name;
      const timestamp = message?.timestamp_ms;
      const content = message?.content;

      if (!senderName || !timestamp || !content) {
        console.log(`Skipping message. Not all data found.`, message);
        continue;
      }

      if (IGNORE_NAMES.has(senderName)) {
        console.log(`Skipping message. Participant is ${senderName}.`, message);
        continue;
      }

      // Date in YYYY-MM-DD.
      const messageDate = new Date(timestamp);
      formattedMessageDate = messageDate.toISOString().substring(0, 10);

      mCounter++;
      appendMessage([senderName, formattedMessageDate, content]);
      console.log(`Found message ${mCounter} to add to spreadsheet!`, message);

      if (MESSAGES_TO_LOG > 0 && mCounter >= MESSAGES_TO_LOG) {
        console.log(`Logged ${mCounter} messages. Moving to next file.`)
        return;
      }
    }

    if (mCounter === 0) console.log('No messages found on this file.');
  };


  /**
   * Processes an individual (JSON) file and import its messages.
   * @param {!File} file in Google Drive (Apps Script) from which to import
   *   messages.
   */
  const importFile = (file) => {
    const filename = file.getName();
    console.log(`Processing file: ${filename}`);

    let fileContent;
    let jsonData;
    try {
      fileContent = file.getBlob().getDataAsString();
      jsonData = JSON.parse(fileContent);
    } catch (e) {
      console.error(e);
      console.log(`Skipping file. Contents do not look like JSON.`);
      return;
    }

    const messages = jsonData?.messages;
    if (!messages) {
      console.log(`Skipping file. No messages found on this file.`);
      return;
    }

    importMessages(messages);
  };

  /**
   * Finds subfolders within a folder and processes them.
   * @param {!Folder} parentFolder Folder in which to look for subfolders.
   */
  const iterateSubFolders = (parentFolder) => {
    const subFolders = parentFolder.getFolders();
    while(subFolders.hasNext()) {
      const subFolder = subFolders.next();
      processFolder(subFolder);
    }
  };

  /**
   * Finds files within a folder and imports its messages into a spreadsheet.
   * @param {!Folder} parentFolder Folder in which to look for files to import.
   */
  const iterateFiles = (parentFolder) => {
    const files = parentFolder.getFiles();
    while(files.hasNext()) {
      const file = files.next();
      importFile(file);
    }
  };

  /**
   * Processes a folder to iterate subfolders and import messages from files.
   * @param {!Folder} folder Folder in Google Drive to process.
   */
  const processFolder = (folder) => {
    const folderName = folder.getName();
    console.log(`Processing folder: ${folderName}`);

    iterateSubFolders(folder);
    iterateFiles(folder);
  };

  /**
   * Iterates a folder to find all files, and import Facebook messages into
   * a spreadsheet. Folder is defined by DRIVE_FOLDER_ID and the spreadsheet
   * by SPREADSHEET_ID.
   */
  const importFacebookMessages = () => {
    const mainFolder = DriveApp.getFolderById(DRIVE_FOLDER_ID);
    if (!mainFolder) throw new Error('Folder id is incorrect.');

    processFolder(mainFolder);
  }

  return importFacebookMessages;
})();


/**
 * Iterates a folder to find all files, and import Facebook messages into
 * a spreadsheet. Folder is defined by DRIVE_FOLDER_ID and the spreadsheet
 * by SPREADSHEET_ID.
 *
 * Run this function on Apps Script to start importing the data.
 */
function importFacebookMessages() {
  _importFacebookMessages();
}