Rake aborted! Don't know how to build task

ruby-on-rails rake rake-task
user1670773 picture user1670773 · Oct 25, 2016 · Viewed 13.8k times · Source

I have a rake task in semester.rake file. It looks like this

namespace :db do
  desc "generate semester data"
  task semester: :environment do
    semester = Semester.create!(name: "SummerSemseter")
    semester = Semester.create!(name: "WinterSemester")
    semester = Semester.create!(name: "Spring Semester")        
  end
end

and I run the task as rake semester. This gives me error 

rake aborted!
Don't know how to build task 'semester' (see --tasks)
/home/john/.rvm/gems/ruby-2.2.4/gems/rake-11.3.0/exe/rake:27:in `<top (required)>'
/home/john/.rvm/gems/ruby-2.2.4/bin/ruby_executable_hooks:15:in `eval'
/home/john/.rvm/gems/ruby-2.2.4/bin/ruby_executable_hooks:15:in `<main>'
(See full trace by running task with --trace)

Why I get this error and what would be the solution?

Answer

Shadwell picture Shadwell · Oct 25, 2016

Your semester task is in a namespace db.

You need therefore to run it with:

rake db:semester

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