Building a NodeJs, TypeScript Project For Reading Excel Files


Part 2

 npm i exceljs csvtojson
import * as csvToJson from 'csvtojson';
import * as ExcelJS from 'exceljs';
import * as fs from 'fs';
import * as path from 'path';

const tempFolderPath = path.join(__dirname, '../', 'temp');

const readFromFile = async (filePath: string) => {
return new Promise((resolve) => {
.then((jsonObj) => {
return resolve(jsonObj);

const writeToTempFile = async (
originalExcelFile: string,
tempCsvFilePath: string,
): Promise<void> => {
if (!fs.existsSync(tempFolderPath)) {

const workbook = new ExcelJS.Workbook();
await workbook.xlsx.readFile(originalExcelFile);

const writeStream = fs.createWriteStream(tempCsvFilePath);
await workbook.csv.write(writeStream, { sheetName: 'books' });

export { tempFolderPath, readFromFile, writeToTempFile };
import * as fs from 'fs';
import * as path from 'path';
import { readFromFile, tempFolderPath, writeToTempFile } from './file-utils';

const run = async () => {
return new Promise(async (resolve) => {
const originalExcelFile = path.join(__dirname, '../', 'data', 'books.xlsx');
const tempCsvFilePath = path.join(tempFolderPath, 'temp_books.csv');
const jsonWriteFile = path.join(tempFolderPath, 'books.json');

console.log(`Reading file from: ${originalExcelFile}`);
await writeToTempFile(originalExcelFile, tempCsvFilePath);
const jsonObj = (await readFromFile(tempCsvFilePath)) as any[];

console.log(`Writing file ${jsonWriteFile}`);
const jsonWrite = fs.createWriteStream(jsonWriteFile);
jsonWrite.write(JSON.stringify(jsonObj, null, 2));

return resolve({
success: true,
message: `File wrote complete: Items Stored: ${jsonObj.length}`,

.catch((e) => console.error(e))
.then((c) => console.log('Complete', c));

LETS GO!!!!!

Pull Request to merge back to main


npm i -D dotenv-cli standard-version conventional-github-releaser
"release": "standard-version --no-verify",
"post:release": "npm run release:github && npm run release:tags",
"release:github": "dotenv -e .env -- conventional-github-releaser -p conventionalcommits",
output from git release
git push --follow-tags origin develop
Release notes in github





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Andrew Allison

15 Years of Professionally putting characters in places that produces great software systems. A life time of hacking on computers.