No route matches controller - scaffold generated code

rubyonrails-talk
1

I am new to RoR, but I have been struggling with a mysterious error for days. I am using a standard installation approach on a clean ubuntu system

I created a very simple application, just reading from a mysql table called dogs. The application was totally generated with scaffold.

rails server -p 3001 #Starts server

When I run, I get the error "No route matches controller"    http://localhost:3001/dogs

If I remove all the link_to cells, the application runs and returns data.

If I put back just one line " <td><%= link_to 'Show', dog %></td>",

I still get the error complaining about the ":action=>"destroy" route.

== scaffold ==

rails g scaffold dog dog_id:integer color:string gender:string dog_name:string --skip-migration

===========Generated Source Code=============

<% @dogs.each do |dog| %>   <tr>     <td><%= dog.dog_id %></td>     <td><%= dog.color %></td>     <td><%= dog.gender %></td>     <td><%= dog.dog_name %></td>     <td><%= link_to 'Show', dog %></td>     <td><%= link_to 'Edit', edit_dog_path(dog) %></td>     <td><%= link_to 'Destroy', dog, :confirm => 'Are you sure?', :method => :delete %></td>   </tr> <% end %>

========= ERROR =========== ## No route matches controller ############ Showing /home/ruby/hub2/app/views/dogs/index.html.erb where line #20 raised: No route matches {:controller=>"dogs", :action=>"destroy", :id=>#<Dog dog_id: 1, color: "Golden", gender: "Female", dog_name: "Daisy">}

Extracted source (around line #20):

17: <td><%= dog.color %></td> 18: <td><%= dog.gender %></td> 19: <td><%= dog.dog_name %></td> 20: <td><%= link_to 'Show', dog %></td> 21: <td><%= link_to 'Edit', edit_dog_path(dog) %></td> 22: <td><%= link_to 'Destroy', dog, :confirm => 'Are you sure?', :method => :delete %></td> 23: </tr>

========== routes.rb ============== Hub2::Application.routes.draw do   resources :dogs end

========= rake routes ============ root@ubu-bob:/home/ruby/hub2# rake routes (in /home/ruby/hub2)     dogs GET /dogs(.:format) {:controller=>"dogs", :action=>"index"}     dogs POST /dogs(.:format) {:controller=>"dogs", :action=>"create"} new_dog GET /dogs/new(.:format) {:controller=>"dogs", :action=>"new"} edit_dog GET /dogs/:id/edit(.:format) {:controller=>"dogs", :action=>"edit"}      dog GET /dogs/:id(.:format) {:controller=>"dogs", :action=>"show"}      dog PUT /dogs/:id(.:format) {:controller=>"dogs", :action=>"update"}      dog DELETE /dogs/:id(.:format) {:controller=>"dogs", :action=>"destroy"}

=== Installation === I followed these instructions on a brand new and fully updated version of ubuntu 10.04

http://castilho.biz/blog/2010/05/08/how-to-install-ruby-on-rails-on-ubuntu-10-04-lucid-lynx/ How to install Ruby on Rails on Ubuntu 10.04 Lucid Lynx     Follow these steps to have a fresh installation of Ruby on Rails in Ubuntu 10.04:

  sudo su   apt-get -y install build-essential   apt-get -y install ruby rdoc libopenssl-ruby   wget http://production.cf.rubygems.org/rubygems/rubygems-1.3.7.tgz   tar zxvf rubygems-1.3.7.tgz   cd rubygems-1.3.7   ruby setup.rb   ln -s /usr/bin/gem1.8 /usr/local/bin/gem   gem install rails ;# (takes awhile with no output.. )

#Installing MySQL gem:

  apt-get -y install ruby-dev libmysql-ruby libmysqlclient-dev   gem install mysql

2

Since you put --skip-migration, could you post table structure? Maybe missing an ID or some other field? Reserved word bug? Sometimes I've had to restart ruby server when working with routes.rb, but shouldn't be necessary with a fresh scaffold. Problem does seem related to routes.rb, I bet using:action controller and id in link_to() would work

3

chris wrote in post #961631:

4

Here is the table definition from the generated schema.rb

  create_table "dogs", :primary_key => "dog_id", :force => true do |t|     t.string "color", :limit => 20     t.string "gender", :limit => 20     t.string "dog_name", :limit => 20   end

I used skip-migration because the table already exists in mysql. When I move from learning mode to development mode, I will need to write code against existing databases, so I can't maintain the database source code in ruby.

5

chris wrote in post #961631:

routes.rb, I bet using:action controller and id in link_to() would work

If you would kindly give me an exact syntax, I'd be like to try it.

I would, however, like to understand why the generated code does not work.

6

Bob T. wrote in post #961643:

Here is the table definition from the generated schema.rb

  create_table "dogs", :primary_key => "dog_id", :force => true do |t|     t.string "color", :limit => 20     t.string "gender", :limit => 20     t.string "dog_name", :limit => 20   end

I used skip-migration because the table already exists in mysql. When I move from learning mode to development mode, I will need to write code against existing databases, so I can't maintain the database source code in ruby.

That's not quite true. You need to learn about rake db:schema:dump.

Anyway, you should be using migrations wherever possible, especially as you learn.

Best,

7

Marnen Laibow-Koser wrote in post #961663:

I used skip-migration because the table already exists in mysql. When I move from learning mode to development mode, I will need to write code against existing databases, so I can't maintain the database source code in ruby.

That's not quite true. You need to learn about rake db:schema:dump.

Let me rephrase .. I don't want to depend on ruby for schema definition, even if it can do it.

Anyway, I did the migrate separately, like this:   rake db:migrate

It brought all the table definitions over from my mysql database.

8

That's the problem:

create_table "dogs", :primary_key => "dog_id", :force => true do |t|

I got a similar error under 2.3.8 with your schema. AR expects ID to be called 'id', you can override it in the model or this would work:

  create_table :dogs' do |t|     t.string "color", :limit => 20     t.string "gender", :limit => 20     t.string "dog_name", :limit => 20   end

I would also recommend using migrations. Sometimes it feels like adding a layer of abstraction for it's own sake, but in the long run it is a great idea.

9

Did you put set_primary_key "dog_id" in the the dog model?

Colin

10

Bob T. wrote in post #961668:

Marnen Laibow-Koser wrote in post #961663:

I used skip-migration because the table already exists in mysql. When I move from learning mode to development mode, I will need to write code against existing databases, so I can't maintain the database source code in ruby.

That's not quite true. You need to learn about rake db:schema:dump.

Let me rephrase .. I don't want to depend on ruby for schema definition, even if it can do it.

Why not? IMHO you are making a huge mistake. The advantages of having Rails manage your DB schema are many -- the app knows what it wants in the DB; you can have your DB schema in version control with your source code; changes to the schema are no longer difficult.

Anyway, I did the migrate separately, like this:   rake db:migrate

It brought all the table definitions over from my mysql database.

How could it do that? rake db:migrate only executes your migration files.

Best,

11

# Here is the solution....

class Dog < ActiveRecord::Base set_primary_key "dog_id" end

12

Someone else found this before I saw yours, but that is the problem. I assumed that scaffold would know what the primary key is , because it was identified in the migrated schema:

schema.rb

  create_table "dogs", :primary_key => "dog_id", :force => true do |t|     t.string "color", :limit => 20     t.string "gender", :limit => 20     t.string "dog_name", :limit => 20   end

Thanks for your help!

Colin Law wrote in post #961671:

13

Regarding migrations -

We use Oracle, MySql , PHP and are just considering using RoR.

If we choose to develop some things in RoR, it will have to learn to get along with the code and the database tables we already have.

If you use only one technology, I understand why you would recommend using that technology exclusively. Personally, I don't believe in getting locked into a particular technology. Thats my choice.

14

Bob T. wrote in post #961705:

Regarding migrations -

Please quote when replying.

We use Oracle, MySql , PHP, Perl/DBI and are just considering using RoR.

If we choose to develop some things in RoR, it will have to learn to get along with the code and the database tables we already have.

And so it can. But you should dump the schema into the schema file as I already suggested.

If you use only one technology, I understand why you would recommend using that technology exclusively. Personally, I don't believe in getting locked into a particular technology. Thats my choice.

I don't either. But while you're developing in Rails, you should use Rails migrations.

It's not great practice to have multiple applications touching the same DB anyway.

Best,

15

Dear all, This is a repost of my question, because the first post is considered as thread hijack. I have changed the title, hopefully this time it's not hijacking any threads :smiley:

I have a silly problem in setting up a relationship between 4 models.

I set these 4 models, ComUser, DefJabatan, DefUserRole, DefKelamin. In each model with name started with 'Def', i put a has_one:ComUser relationship. So naturally i have 3 belongs_to relationship in ComUser. I do a simple query in the controller: @users = ComUser.find(:first) and in the view, i simply put a object debug: <%=debug(@users)%>

and I get this:

--- !ruby/object:ComUser attributes:   def_jabatan_id: "1"   created_at: 2010-11-16 04:31:35   def_user_role_id: "1"   gsm: "-"   updated_at: 2010-11-16 04:31:35   alamat: "-"   username: admin   id: "1"   def_kelamin_id: "1"   password: admin   online_status: "2" attributes_cache: {}

I'm getting a feeling that I didn't set the relationship right, because i don't see any attributes addition in the ComUser from the model started with Def-something that i create above..

Am I missing something here, like violating a naming convention or something?

I even tries to alter the table by implicitly put a foreign key in the table for ComUser model using sql statements, and the debug result is still the same. How can i make this relationship work?

Thanks

PS. I put the code snippet that i use for migrating the database and defining the relationship below.

Regards, Arga

ComUser < ActiveRecord::Base    belongs_to :DefKelamin    belongs_to :DefUserRole    belongs_to :DefJabatan Migration:     create_table :com_users do |t|     t.timestamps     t.references :def_jabatan, :null => false     t.integer :def_kelamin_id, :null => false     t.references :def_user_role, :null => false     t.column :username,'varchar(20)', :null => false     t.column :password,'varchar(20)', :null => false     end

DefJabatan < ActiveRecord::Base    has_one:ComUser Migration:     create_table :def_jabatans do |t|     t.timestamps     t.column :jabatan,'varchar(20)', :null => false     end

DefUserRole < ActiveRecord::Base    has_one:ComUser Migration:     create_table :def_user_roles do |t|     t.timestamps     t.column :role,'varchar(20)', :null => false     t.string :description, :null => false     t.string :icon     end

DefKelamin < ActiveRecord::Base     has_one :ComUser Migration:     create_table :def_kelamins do |t|     t.timestamps     t.column :kelamin,'varchar(10)', :null => false     end

16

arga aridarma wrote in post #961713:

Dear all, This is a repost of my question, because the first post is considered as thread hijack. I have changed the title, hopefully this time it's not hijacking any threads :smiley:

Still hijacking. Please start a new thread.

Best,

17

arga aridarma wrote in post #961713:

Dear all, This is a repost of my question, because the first post is considered as thread hijack. I have changed the title, hopefully this time it's not hijacking any threads :smiley:

Still hijacking. Please start a new thread.

What are you talking about? I'm reading this via the mailing list; on this end of things _both_ of arga's mails are hijacking nothing.

18

If you check via Google Groups, it did.

19

> arga aridarma wrote in post #961713: >> Dear all, >> This is a repost of my question, because the first post is considered >> as >> thread >> hijack. >> I have changed the title, hopefully this time it's not hijacking any >> threads :smiley: > > Still hijacking. Please start a new thread.

What are you talking about? I'm reading this via the mailing list; on this end of things _both_ of arga's mails are hijacking nothing.

If you check via Google Groups, it did.

Huh.

20

Link to the original thread, which was originally titled “No route matches controller - scaffold generated code”

http://groups.google.com/group/rubyonrails-talk/browse_thread/thread/ff7ff1c1dd447e90