Heroku Blog

Bundler groups are commonly used to specify which dependencies of your application are needed in a given environment. You may have something like this in your Gemfile: group :test do gem “rspec” end Using the “test” group in this case allows you to specify the gems that are needed to test your application. Since you won’t need these gems in production, you can speed up installation by ignoring the “test” group. Bundler provides this ability through the –without option: bundle install –without test You can currently access this functionality on Heroku by setting the BUNDLE_WITHOUT config var in your application.…

In December, we rolled out the public beta of a sweet new logging system for Heroku. The new system combines log output from your app’s processes and Heroku’s system components (such as the HTTP router). With all of your logs collated into a single, time-ordered stream, you get an integrated view of everything happening in your app. Here’s a sample: $ heroku logs 2010-10-21T14:11:16-07:00 app[web.2]: Processing PostController#list (for 208.16.84.131 at 2010-10-21 14:11:16) [GET] 2010-10-21T14:11:16-07:00 app[web.2]: Rendering template within layouts/application 2010-10-21T14:11:16-07:00 app[web.2]: Rendering post/list 2010-10-21T14:11:16-07:00 app[web.2]: Rendered includes/_header (0.1ms) 2010-10-21T14:11:16-07:00 app[web.2]: Completed in 150ms (View: 27, DB: 121) | 200 OK…

The improved maintenance mode we described last month is now standard for all existing and new apps. This new maintenance mode is faster and much more scalable, particularly for apps with more than fifty dynos. It handles maintenance mode at the HTTP router, providing an instantaneous response for turning maintenance mode on or off regardless of the size of your app. It uses a standard page which serves with an HTTP 503 code. (If you preferred the old maintenance mode, you can manually add it to your app by installing this middleware and setting a MAINTENANCE config var.) Read the…

When your app is crashed, out of resources, or misbehaving in some other way, Heroku serves error pages to describe the problem. We also have a single page for platform errors, once known as the ouchie guy (pictured right). While the approach of showing error information directly via the web has worked well enough, there was room for improvement on both developer visibility and professionalism of presentation to end users. With that in mind, we’ve reworked our approach on error handling, making improvements that should make it much easier for you, the developer, to diagnose and correct errors in your…