Building LunchBot: A Simple Slack Bot for Lunch Menus
Lunch is a surprisingly frequent topic in office Slack channels.
Someone asks where to eat, someone else checks a restaurant website, and a few minutes later the whole discussion starts again the next day.
I thought it would be fun to automate that process.
So I built LunchBot, a small Slack bot that fetches lunch menus from nearby restaurants and posts them directly into Slack.
The Idea
The idea was simple:
- Fetch lunch menus from restaurant websites.
- Extract the relevant menu information.
- Post the results into Slack.
Instead of opening multiple websites every day, the whole team could just type a command and instantly see the available options.
Tech Stack
The project is intentionally lightweight and built with just a few tools.
Node.js
The bot runs on Node.js, which makes it easy to handle asynchronous tasks like HTTP requests and scraping.
Cheerio
To extract menu data from restaurant websites, I used Cheerio.
It provides a jQuery-like API for parsing HTML, which makes scraping structured data much easier.
Slack API
The Slack API allows the bot to send messages directly to a Slack channel. Once the menus are collected and formatted, the bot posts them as a message.
How It Works
Fetching Menus
LunchBot requests the restaurant websites and downloads the HTML content.
Each restaurant page has its own structure, so I wrote small parsing functions that extract the relevant menu items.
Parsing the Data
Using Cheerio, the bot selects the elements containing the menu text and converts them into a cleaner format.
Posting to Slack
Once the menu data is prepared, the bot sends a formatted message to Slack so the team can see the options immediately.
Challenges
Even for a small project, a few things turned out to be trickier than expected.
Different website structures
Each restaurant page was structured differently, so the scraper logic had to be adapted for each one.
Formatting messages for Slack
Slack messages have their own formatting rules, so getting the menus to display nicely required a bit of experimentation.
Handling async requests
Fetching multiple websites at once means dealing with asynchronous code. Using async/await helped keep things readable.
What I Learned
LunchBot was a great small project for experimenting with:
- web scraping
- Slack integrations
- Node.js automation scripts
More importantly, it turned out to be genuinely useful. Once it was running, it quickly became part of the daily workflow in our office.
What Came Next
Over time I started thinking about improving the project with things like:
- caching menus
- a web interface
- better formatting and error handling
That eventually led to a rebuilt version of the project called PasiLunch, which I wrote about in a later post.
The original LunchBot fetching daily menus and posting them to Slack.