Debugging

Raindeer is an asynchronous framework where many things/tasks (Fibers) are happening at once. This can make debugging a little harder if you don't know what you're doing, as code can error and the application can move on to the next task before you're finished reading the error and trying to debug it.

Debug Mode

In development Raindeer will automatically block the current asynchronous fiber and show the backtrace when an exception is raised.

Set RAIN_DEBUG=1 to RAIN_DEBUG=0 in production so that broken fibers don't block others.

Asynchronous Mode

RAIN_ASYNC=1 is the default. In this async environment we must first block the fiber:

Fiber.blocking { binding.irb }

See also: https://socketry.github.io/async/guides/debugging/index

Synchronous Mode

Set RAIN_ASYNC=0 to run the server synchronously, making familiar non-blocking debugging techniques easy such as:

p variable
puts variable
binding.pry
binding.irb