I’m working on a Rails application deployed to Heroku using the Unicorn web server. My app needs to perform some browser automation tasks like web scraping or taking screenshots of web pages.
I’ve come across several tutorials showing how to set up PhantomJS or other headless browsers on Heroku’s Cedar stack, but I can’t find clear information about whether this is supported when using Unicorn as the web server.
Has anyone successfully integrated headless browser functionality (like Selenium with Chrome headless or similar tools) on a Heroku Rails app running Unicorn? Are there any specific configuration changes or buildpacks I need to consider for this setup to work properly?
Any guidance or working examples would be really helpful since I’m not sure if the server choice affects the ability to run headless browsers on Heroku.
honestly, unicorn vs puma doesn’t matter for headless browsers - they’re just separate processes your rails app spawns. I’ve been running playwright-ruby with heroku’s chrome buildpack and it’s way more stable than selenium. uses less memory than puppeteer too.
Headless browsers on Heroku are a nightmare. I’ve dealt with memory issues, timeouts, and config hell more times than I want to remember.
What actually works? Move the browser stuff off your server completely. Don’t fight Chrome in a tiny Heroku dyno - you’ll lose every time.
I run automated workflows that handle scraping and screenshots externally. My Rails app just triggers them when needed and gets results back. No buildpack drama, no memory limits, no crashed dynos.
I use Latenode for this setup. It handles browser automation without the server headaches and scales separately from my main app. Just simple API calls from Rails.
Your Unicorn choice doesn’t matter since the heavy work happens elsewhere. You skip all those Chrome flags and memory management issues that make Heroku deployments miserable.
The memory and timeout issues everyone’s talking about? That’s exactly why I ditched headless browsers on Heroku dynos years ago.
Unicorn doesn’t touch browser automation - those processes run separately. But shoving Chrome into a dyno with limited RAM while your Rails app fights for resources? Recipe for disaster.
I used to waste hours tweaking Chrome flags and killing zombie processes. Then it hit me - I was solving the wrong problem.
Now I handle all browser automation externally through workflows that run independently of my Rails deployment. My app just makes simple API calls to trigger scraping or screenshot tasks and gets clean results back.
No buildpack headaches. No memory limits. No dyno crashes. No background job queues eating resources.
Latenode handles the browser stuff while my Rails app stays lightweight and focused. The automation scales separately and doesn’t mess with my web server performance.
Way cleaner than wrestling with Chrome inside Heroku containers.
I encountered a similar issue a few months ago when creating a Rails app for generating PDFs from web content. The choice of server isn’t a limiting factor because headless browsers operate as separate processes that Rails manages as necessary. I utilized the heroku-buildpack-google-chrome along with the selenium-webdriver gem to implement headless Chrome. It’s crucial to configure Chrome correctly for Heroku by adding the flags --no-sandbox and --disable-dev-shm-usage to prevent crashes.
One major challenge I faced was related to memory management. Heroku dynos have limited RAM, and Chrome can quickly exhaust it, so it’s important to implement proper cleanup procedures to terminate browser instances after executing tasks. Additionally, I recommend leveraging Sidekiq or another background job processor for these operations, as they can be quite time-consuming.
Been running headless automation on Heroku with Unicorn for two years. Web server choice doesn’t matter since the browser runs as a separate process. I use Puppeteer with the jontewks/puppeteer buildpack instead of Selenium - it’s more reliable and uses fewer resources than Chrome with Selenium. Setup’s straightforward: add the buildpack and configure Puppeteer to use the bundled Chromium binary. Set proper timeouts in your Rails code though. Heroku kills requests after 30 seconds, so you need background processing for long scraping tasks. I use DelayedJob over Sidekiq - easier setup. Memory management’s crucial but doable. Process pages in batches and close browser instances when done. Basic dynos can’t handle multiple concurrent browsers well, so scale up if you’re doing heavy automation.
I’ve deployed several Rails apps on Heroku with Unicorn for browser automation. The web server doesn’t matter much - headless browsers spawn as child processes whether you’re using Unicorn, Puma, or Passenger. What really matters is process management and resource allocation. Chrome headless works better for me using heroku-buildpack-chromedriver with Capybara instead of Selenium. The game-changer was setting up proper process monitoring to catch when Chrome instances turn into zombies or eat up too much memory. You need background job processing for anything more complex than basic page visits. Found this out the hard way when my dynos kept timing out on scraping tasks. If you’re doing frequent automation, R2M dynos crush standard dynos - the extra RAM makes a huge difference when Chrome has to render JS-heavy pages.