There are multiple debug techniques are available with RoR, Please use the
below techniques as much as you can, while you do programming in RoR.
1. install ruby-debug
then need to start application by ruby script/server --debugger
And place word 'debugger' anywhere in your code and once you run your
application, it stops running from where you have placed 'debugger'. We
can say that debugger is the breakpoint
Then you can use following commands
n - move next line
l - display the current line after the debugger
c - continue
You can also check the readme of the ruby-debug
2. You can use puts,exit etc.
3. You can use logger.debug "The object is #{@object}" or
RAILS_DEFAULT_LOGGER.debug @object
4. In view, you can also use <%=debug @object %>
5. You can simultaneously check your log by running tail -f lod/development.log in the another terminal or you can also use tail -n log/development.log where n is any numeric number
6. We can use Exception Notifier plugin in our production environment so that we gets an notification mail if any error occurs on production