Ruby on Rails 4中的“ NameError：未初始化的常量新闻通讯”，但未在开发中

Question

I have an app on Heroku. I added a new model and a controller for "newsletter". In development, everything works fine. Then I ran these lines of code:

git commit -a -m "added newsletter"
git push origin master
git push heroku master
heroku run rake db:migrate

But after trying to get the index page, I got this message:

The page you were looking for doesn't exist.

You may have mistyped the address or the page may have moved.

I ran heroku run rails console and typed in: Newsletter.connection

irb(main):001:0> Newsletter.connection
NameError: uninitialized constant Newsletter
        from (irb):1
        from /app/vendor/bundle/ruby/2.2.0/gems/railties-4.2.5/lib/rails/commands/console.rb:110:in `start'
        from /app/vendor/bundle/ruby/2.2.0/gems/railties-4.2.5/lib/rails/commands/console.rb:9:in `start'
        from /app/vendor/bundle/ruby/2.2.0/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:68:in `console'
        from /app/vendor/bundle/ruby/2.2.0/gems/railties-4.2.5/lib/rails/commands/commands_tasks.rb:39:in `run_command!'
        from /app/vendor/bundle/ruby/2.2.0/gems/railties-4.2.5/lib/rails/commands.rb:17:in `<top (required)>'
        from /app/bin/rails:9:in `require'
        from /app/bin/rails:9:in `<main>'
irb(main):002:0> 

Then I ran Heroku logs :

2016-02-14T20:24:36.918613+00:00 heroku[router]: at=info method=GET path="/newsletters" host=evening-basin-18662.herokuapp.com request_id=a7acad04-63e4-468f-9eac-bfec23c72773 fwd="87.245.109.31" dyno=web.1 connect=0ms service=13ms status=404 bytes=1829
2016-02-14T20:24:36.919403+00:00 app[web.1]: Started GET "/newsletters" for 87.245.109.31 at 2016-02-14 20:24:36 +0000
2016-02-14T20:24:36.924135+00:00 app[web.1]: 
2016-02-14T20:24:36.924138+00:00 app[web.1]: ActionController::RoutingError (uninitialized constant NewslettersController):

Where did I go wrong? Thanks in advance!

Edit: models/newsletter.rb

class Newsletter < ActiveRecord::Base
end

controllers/newsletters_controller.rb

class NewslettersController < ApplicationController
  def index
    @newsletters = Newsletter.all
  end

  def new
    @newsletter = Newsletter.new
  end

  def create
    @newsletter = Newsletter.new(newsletter_params)
    if @newsletter.save
      # @user = User.find(current_user.id)
      #ExampleMailer.sample_email(@user).deliver
      redirect_to newsletters_path
    else
      render 'new'
    end
  end

  private

  def newsletter_params
    params.require(:newsletter).permit(:name)
  end


end

config/routes.rb

resources :newsletters

Edit 2:

Solved by Frederich Cheung.

Frederick Cheung asked: "Did you definitely commit newsletter.rb?"

Then, I did this:

git add .
git commit -m "add newsletter"
git push origin master
git push heroku master

And after that, it worked.

Answer 1

Because it is due to an error in git handling, here a more verbose explanation to what Michael Cruz already pointed out:

For more info have a look at the git commit documentation

git commit -a same as

git commit --all

Tell the command to automatically stage files that have been modified and deleted, but new files you have not told Git about are not affected .

For more info have a look at the git add documentation

git add

This command [git add] updates the index using the current content found in the working tree, to prepare the content staged for the next commit. It typically adds the current content of existing paths as a whole , but with some options it can also be used to add content with only part of the changes made to the working tree files applied, or remove paths that do not exist in the working tree anymore.

Is my file tracked?

To find out if your file is tracked by git you can run git status myFileName.rb . If it returns an error it is not tracked yet.

Answer 2

Frederick Cheung asked: "Did you definitely commit newsletter.rb?"

Then, I did this:

git add .
git commit -m "add newsletter"
git push origin master
git push heroku master

And after that, it worked. (Weird, because I'm pretty sure, I ran git commit -a -m "add newsletter" )