Having trouble starting rails server - no luck with googling it

Question

Trying to start the rails server to complete "Learn Ruby on Rails" by Kehoe and keep getting psych errors and have no idea how to troubleshoot.

Here is the output:

/Dropbox/workspace/learn-rails$ rails s
/home/mark/.rvm/gems/ruby-2.1.2@global/gems/psych-2.0.6/lib/psych.rb:370:in `parse': (<unknown>): mapping values are not allowed in this context at line 6 column 15 (Psych::SyntaxError)
from /home/mark/.rvm/gems/ruby-2.1.2@global/gems/psych-2.0.6/lib/psych.rb:370:in `parse_stream'
from /home/mark/.rvm/gems/ruby-2.1.2@global/gems/psych-2.0.6/lib/psych.rb:318:in `parse'
from /home/mark/.rvm/gems/ruby-2.1.2@global/gems/psych-2.0.6/lib/psych.rb:245:in `load'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/figaro-1.0.0/lib/figaro/application.rb:60:in `parse'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/figaro-1.0.0/lib/figaro/application.rb:56:in `block in raw_configuration'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/figaro-1.0.0/lib/figaro/application.rb:56:in `yield'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/figaro-1.0.0/lib/figaro/application.rb:56:in `raw_configuration'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/figaro-1.0.0/lib/figaro/application.rb:64:in `global_configuration'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/figaro-1.0.0/lib/figaro/application.rb:32:in `configuration'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/figaro-1.0.0/lib/figaro/application.rb:42:in `each'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/figaro-1.0.0/lib/figaro/application.rb:36:in `load'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/figaro-1.0.0/lib/figaro.rb:23:in `load'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/figaro-1.0.0/lib/figaro/rails/railtie.rb:5:in `block in <class:Railtie>'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/activesupport-4.1.6/lib/active_support/lazy_load_hooks.rb:36:in `call'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/activesupport-4.1.6/lib/active_support/lazy_load_hooks.rb:36:in `execute_hook'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/activesupport-4.1.6/lib/active_support/lazy_load_hooks.rb:45:in `block in run_load_hooks'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/activesupport-4.1.6/lib/active_support/lazy_load_hooks.rb:44:in `each'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/activesupport-4.1.6/lib/active_support/lazy_load_hooks.rb:44:in `run_load_hooks'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/railties-4.1.6/lib/rails/application.rb:123:in `initialize'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/railties-4.1.6/lib/rails/railtie.rb:171:in `new'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/railties-4.1.6/lib/rails/railtie.rb:171:in `instance'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/railties-4.1.6/lib/rails/application.rb:90:in `inherited'
from /home/mark/Dropbox/workspace/learn-rails/config/application.rb:10:in `<module:LearnRails>'
from /home/mark/Dropbox/workspace/learn-rails/config/application.rb:9:in `<top (required)>'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/railties-4.1.6/lib/rails/commands/commands_tasks.rb:79:in `require'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/railties-4.1.6/lib/rails/commands/commands_tasks.rb:79:in `block in server'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/railties-4.1.6/lib/rails/commands/commands_tasks.rb:76:in `tap'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/railties-4.1.6/lib/rails/commands/commands_tasks.rb:76:in `server'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/railties-4.1.6/lib/rails/commands/commands_tasks.rb:40:in `run_command!'
from /home/mark/.rvm/gems/ruby-2.1.2@learn-rails/gems/railties-4.1.6/lib/rails/commands.rb:17:in `<top (required)>'
from bin/rails:8:in `require'
from bin/rails:8:in `<main>'

Answer 1

Psych is a YAML parser and emitter. I guess that either you have a malformed database.yml or wrong encoding or something like that.

Answer 2

鉴于Psych是处理YAML文件的瑰宝，并且您的错误表示语法错误，因此在config/目录中某个位置的YAML文件格式错误，可能性很大。