Created New User - User Exists? - ruby-on-rails

Question

I went to create a user=User.new (:screen_name => "jeff holmes", :email "jeff92#jeff.com", :password "1234") I had some validations I was trying to see if it would pass:
class User < ActiveRecord::Base
validates_uniqueness_of :screen_name, :email
validates_length_of :screen_name, :within => 4...20
validates_length_of :password, :within => 4...20
validates_length_of :email, :within => 6...50
def validate
errors.add(:email, 'must be valid.') unless email.include? ("#")
errors.add(:screen_name, 'cannot include spaces.') if screen_name.include?(" ")
end
end
After I try to create the user all this stuff pops up and I have no idea what it is.
NameError: undefined local variable or method `user' for main:Object
from (irb):3
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/commands/console.rb:110:in `start'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/commands/console.rb:9:in `start'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/commands/commands_tasks.rb:68:in `console'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/commands/commands_tasks.rb:39:in `run_command!'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/railties-4.2.1/lib/rails/commands.rb:17:in `<top (required)>'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activesupport-4.2.1/lib/active_support/dependencies.rb:274:in `require'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activesupport-4.2.1/lib/active_support/dependencies.rb:274:in `block in require'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activesupport-4.2.1/lib/active_support/dependencies.rb:240:in `load_dependency'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activesupport-4.2.1/lib/active_support/dependencies.rb:274:in `require'
from /Users/coreyholmes/RubymineProjects/worklink/bin/rails:8:in `<top (required)>'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activesupport-4.2.1/lib/active_support/dependencies.rb:268:in `load'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activesupport-4.2.1/lib/active_support/dependencies.rb:268:in `block in load'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activesupport-4.2.1/lib/active_support/dependencies.rb:240:in `load_dependency'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activesupport-4.2.1/lib/active_support/dependencies.rb:268:in `load'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/spring-1.3.6/lib/spring/commands/rails.rb:6:in `call'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/spring-1.3.6/lib/spring/command_wrapper.rb:38:in `call'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/spring-1.3.6/lib/spring/application.rb:183:in `block in serve'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/spring-1.3.6/lib/spring/application.rb:156:in `fork'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/spring-1.3.6/lib/spring/application.rb:156:in `serve'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/spring-1.3.6/lib/spring/application.rb:131:in `block in run'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/spring-1.3.6/lib/spring/application.rb:125:in `loop'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/spring-1.3.6/lib/spring/application.rb:125:in `run'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/spring-1.3.6/lib/spring/application/boot.rb:18:in `<top (required)>'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:54:in `require'
from /Users/coreyholmes/.rbenv/versions/2.2.2/lib/ruby/2.2.0/rubygems/core_ext/kernel_require.rb:54:in `require'
Then after all that stuff pops up I go user.save and this appears.
NameError: undefined local variable or method `user' for main:Object
Whats going on? What am I doing wrong here.
Thanks

Answer 1

Not 100% certain on the problem at hand but here's a little overview of the create process
user = User.new # creates the user object/instance but DOES NOT save or populate the ID column/attribute/method
# OR ...
user = User.new(params[:user]) # often what you see in a controller action
user.valid? # checks to ensure your validations pass ... duh :)
user.save # saves the users
# from here, you can do a few things:
user.persisted? # this checks if the user was saved in the DB
user.id
# will now show you the user's id ...
# in your original post's code it appears you check for the id _before_ the save and it has to be saved before that attribute/method is populated.
The User Exists is Rails checking to see if that user is already in the DB before it tries to save it (my sense is that your User model validates the email and screen_name methods/attributes)
As for seeing the user after it's created you can do a couple of things:
If you're in a console, just type user to get the output.
In a web view (read: browser), you would go to http://localhost:3000/users/ID_OF_NEW_USER (this assumes you have a show action in your UsersController and a show view (show.html.erb or show.html.haml) ... and if you generated a scaffold (rails generate scaffold User email:string ..., you have these!)
Again, not totally sure I understood your request but I hope this helps you understand this flow a little better.
UPDATE:
Just saw the additions to your post. This code is incorrect:
user=User.new (:screen_name => "jeff holmes", :email "jeff92#jeff.com", :password "1234")
It should be
user=User.new (:screen_name => "jeff_holmes", :email => "jeff92#jeff.com", :password => "1234") # note the missing '=>' for email and password and the space in the screen_name, which is invalid according to the model

Answer 2

You are doing fine.
user = User.create name: "name", email: "email#test.com", password: "123456"
By calling the create method of a class its running all validations. Unless they failed its calling the save method. Since user is a new_object? rails will create the user.
After that you are having the user instance in your variable "user".
The other way is
user = User.new
user.email = "test#test.de"
....
user.save
Here again, the save method will call validations, and if they pass it will save the object to the database.
You can get the ID with user.id or User.last (which will load the latest user out of the database).
The best way to test those behaviors and play with it is the rails console. you can run it with rails c
you are doing fine.
just a little hint: have a look at the gem called "devise" which implements you a complete user-auth logic within 15 minues. no line of code needs to be written.