Rake任務保持失敗

Question

我試圖設置我的開發環境來處理使用Mongoid的現有項目。我已經運行包安裝並運行良好，但現在我想建立數據庫，和我跑rake db:setup

下面是輸出：

[1] $ rake db:setup --trace                                          ✘ 
** Invoke db:setup (first_time) 
** Invoke db:create (first_time) 
** Invoke environment (first_time) 
** Execute environment 
rake aborted! 
You have a nil object when you didn't expect it! 
You might have expected an instance of Array. 
The error occurred while evaluating nil.+ 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/bundler/gems/cantango-36e3ce152717/lib/cantango/configuration/registry.rb:31:in `register' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/bundler/gems/cantango-36e3ce152717/lib/cantango/configuration/candidate_registry.rb:10:in `register' 
/home/chintanparikh/Documents/Work/project_name/config/initializers/cantango.rb:8:in `block in <top (required)>' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/bundler/gems/cantango-36e3ce152717/lib/cantango.rb:23:in `configure' 
/home/chintanparikh/Documents/Work/project_name/config/initializers/cantango.rb:2:in `<top (required)>' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:234:in `load' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:234:in `block in load' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:223:in `block in load_dependency' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:640:in `new_constants_in' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:223:in `load_dependency' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:234:in `load' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/railties-3.1.3/lib/rails/engine.rb:556:in `block (2 levels) in <class:Engine>' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/railties-3.1.3/lib/rails/engine.rb:555:in `each' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/railties-3.1.3/lib/rails/engine.rb:555:in `block in <class:Engine>' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/railties-3.1.3/lib/rails/initializable.rb:30:in `instance_exec' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/railties-3.1.3/lib/rails/initializable.rb:30:in `run' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/railties-3.1.3/lib/rails/initializable.rb:55:in `block in run_initializers' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/railties-3.1.3/lib/rails/initializable.rb:54:in `each' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/railties-3.1.3/lib/rails/initializable.rb:54:in `run_initializers' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/railties-3.1.3/lib/rails/application.rb:96:in `initialize!' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/railties-3.1.3/lib/rails/railtie/configurable.rb:30:in `method_missing' 
/home/chintanparikh/Documents/Work/project_name/config/environment.rb:5:in `<top (required)>' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:240:in `require' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:240:in `block in require' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:223:in `block in load_dependency' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:640:in `new_constants_in' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:223:in `load_dependency' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/activesupport-3.1.3/lib/active_support/dependencies.rb:240:in `require' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/railties-3.1.3/lib/rails/application.rb:83:in `require_environment!' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0/gems/railties-3.1.3/lib/rails/application.rb:193:in `block (2 levels) in initialize_tasks' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/task.rb:227:in `call' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/task.rb:227:in `block in execute' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/task.rb:222:in `each' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/task.rb:222:in `execute' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/task.rb:166:in `block in invoke_with_call_chain' 
/home/chintanparikh/.rvm/rubies/ruby-1.9.3-p0/lib/ruby/1.9.1/monitor.rb:211:in `mon_synchronize' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/task.rb:159:in `invoke_with_call_chain' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/task.rb:187:in `block in invoke_prerequisites' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/task.rb:185:in `each' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/task.rb:185:in `invoke_prerequisites' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/task.rb:165:in `block in invoke_with_call_chain' 
/home/chintanparikh/.rvm/rubies/ruby-1.9.3-p0/lib/ruby/1.9.1/monitor.rb:211:in `mon_synchronize' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/task.rb:159:in `invoke_with_call_chain' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/task.rb:187:in `block in invoke_prerequisites' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/task.rb:185:in `each' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/task.rb:185:in `invoke_prerequisites' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/task.rb:165:in `block in invoke_with_call_chain' 
/home/chintanparikh/.rvm/rubies/ruby-1.9.3-p0/lib/ruby/1.9.1/monitor.rb:211:in `mon_synchronize' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/task.rb:159:in `invoke_with_call_chain' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/task.rb:152:in `invoke' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/application.rb:141:in `invoke_task' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/application.rb:99:in `block (2 levels) in top_level' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/application.rb:99:in `each' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/application.rb:99:in `block in top_level' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/application.rb:108:in `run_with_threads' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/application.rb:93:in `top_level' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/application.rb:71:in `block in run' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/application.rb:158:in `standard_exception_handling' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/lib/rake/application.rb:68:in `run' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/gems/rake-10.0.1/bin/rake:37:in `<top (required)>' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/bin/rake:19:in `load' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/bin/rake:19:in `<main>' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/bin/ruby_noexec_wrapper:14:in `eval' 
/home/chintanparikh/.rvm/gems/ruby-1.9.3-p0@global/bin/ruby_noexec_wrapper:14:in `<main>' 
Tasks: TOP => db:setup => db:create => environment 

有誰知道如何解決這個？它看起來在創建步驟上失敗了。

乾杯。

Answer 1

MongoDB是一個無模式數據庫。您不需要使用它的任何rake db:{}函數。你需要做的只有安裝mongodb然後啓動服務器。你可以找到更多關於安裝MongoDB的信息here