Ruby Forum Ruby on Rails > Scaffolding for pre-existing database table in 2.0.1

Hi,

first of all I will apologize in advance for my presumably noobish
question, but I'm only starting to learn Rails and am a little
confused with all the changes in 2.0.1. There are as good as no
tutorials out yet and the 2 or 3 screencasts I've seen deal with the
creation of both the app and the database.

Now my problem is that I already have a database with a fair amount of
records in it (contacts with columns id:integer, first_name:string,
last_name:string). In order to get a simple CRUD interface (that's all
I want for now), with the pre-2.0 version of Rails,  I could simply
"generate scaffold contacts" and the framework would provide me with
all the necessary files to get started with (controller, model and
views).

When I try the same command ("generate scaffold contacts") in 2.0.1 it
will almost do the same thing, but somehow it misses all the fields
from the database. The list-view solely contains a long listing of
"Show Edit Destroy" lines (no first or last name listed here). When I
click on Edit, the form just provides me with an update button. So no
fields for first- and last name here either.

Is it supposed to be this way now in 2.0.1? If so, what can I do to
bring back the old functionality?

Regards,

Sebastian

New way is to specify the fields.

script/generate scaffold person first_name:string last_name:string



On Dec 10, 2007 1:46 PM, Sebastian <sebastian.vogelsang@gmail.com> 
wrote:

> records in it (contacts with columns id:integer, first_name:string,
> click on Edit, the form just provides me with an update button. So no
> fields for first- and last name here either.
>
> Is it supposed to be this way now in 2.0.1? If so, what can I do to
> bring back the old functionality?
>
> Regards,
>
> Sebastian
> >
>


--
Ryan Bigg
http://www.frozenplague.net

Hey Ryan,

thanks for the quick answer.

I tried that multiple times before via the generator function in the
RadRails IDE and it didn't work (nothing happened, no error message).
It simply didn't create any controllers/views/models.
Just now I tried it again via the windows console, et voilà, ROR
creates all the classes like it used to. So it seems that this
malfunction was due to a bug/2.0-incompatibility in RadRails. Hope,
they'll fix this soon!

Thanks again,

Sebastian

On 12/9/07, Ryan Bigg <radarlistener@gmail.com> wrote:
> New way is to specify the fields.
>
> script/generate scaffold person first_name:string last_name:string

And if the table already exists you might want to add --skip-migration

  script/generate scaffold person first_name:string last_name:string
--skip-migration

--
Rick DeNatale

My blog on Ruby
http://talklikeaduck.denhaven2.com/

I did this yesterday. You _HAVE_ to specify --skip-migration in case
its an existing model, else it will stop the whole "generate scaffold"
task before it creates the controller.

Ok, been following this all day.

Scaffolding is really not great for production, but it is nice to have 
it
build the forms for you. It saves me some typing at least, and I find 
that's
what most people are after with the scaffolding.  With that in mind, I 
took
some of the old scaffolding code and made it into a gem.  It's designed 
to
work off of a pre-existing model.

sudo gem install scaffold_form_generator

Then just do

ruby script/generate scaffold_form User users

It will build these files

/app/views/users/new.html.erb
/app/views/users/edit.html.erb
/app/views/users/_form.html.erb

The form builder skips created_at, updated_at, lock_version, and 
anything
with _id at the end.  It also makes boolean fields checkboxes instead of
true/false dropdowns.

Learn more at

http://scaffoldform.rubyforge.org

Now, it doesn't do "everything" completely RESTful yet but it's a really
good start. If you have suggestions, let me know. It's not going to ever 
be
extended to handle relationships - I looked into it and it's not worth
trying - too hard to know what you are trying to relate, what you want 
to
show in your dropdowns, etc.

-bph

Ryan Bigg wrote:
> New way is to specify the fields.
> 
> script/generate scaffold person first_name:string last_name:string
> 

I'm considering Ruby on Rails, but I already have a big database schema, 
and I'd rather not re-type firstname:string lastname:string, for the 
dozens of fields in my dozens of tables. Is there some way for Ruby to 
build the scaffold based on what it finds in the existing database? 
Wasn't that the whole point in previous versions? This seems like a big 
step backwards....

The idea is that Rails doesn't know which of your fields you want to
include, or what kind they are.

It'll be easier for you to type them and design your own layout.

... and one more comment/question... how can I prevent Ruby from 
pluralizing my model. Say my table is called "game." If I try this new 
scaffold with...

ruby script/generate scaffold game name:string

... what I get in my file structure is "games" (plural), but the table 
in my existing database is "game" (singular). I then get SQL errors on 
like "Table db.games doesn't exist."

Not too sure on that, I was sure that scaffolding named everything
correctly.

On Jan 8, 2008 3:51 PM, Mr Mapes <rails-mailing-list@andreas-s.net> 
wrote:

> --
> Posted via http://www.ruby-forum.com/.
>
> >
>


--
Ryan Bigg
http://www.frozenplague.net
Feel free to add me to MSN and/or GTalk as this email.

On Jan 7, 2008 11:21 PM, Mr Mapes <rails-mailing-list@andreas-s.net> 
wrote:

>  --
> Posted via http://www.ruby-forum.com/.
>
>  You're not following conventions, which is explained by your use of the
legacy schema. Rails assumes that table names are plural and model names 
are
singular.

What you actually need to do is run the scaffold as such:

   ruby script/generate scaffold game name:string

Then open up app/models/game.rb

Add the "set_table_name" method call to tell the model to use the 
singular
table.

class Game < ActiveRecord::Base
   set_table_name "game"
end


If your primary key is not called "id" then you can specify that as 
well. Be
warned though - Rails likes integers for its keys.

 class Game < ActiveRecord::Base
   set_table_name "game"
   set_primary_key "game_id"
end

Finally, Rails is not about scaffolding. That was a marketing trick to 
get
people sucked in. Most people who do Rails professionally don't use
scaffolding at all, as it often generates a bunch of code you don't 
need, or
is not complex enough to handle the basic tasks.

On Jan 8, 8:38 am, "Brian Hogan" <bpho...@gmail.com> wrote:

> Finally, Rails is not about scaffolding. That was a marketing trick to get
> people sucked in. Most people who do Rails professionally don't use
> scaffolding at all, as it often generates a bunch of code you don't need, or
> is not complex enough to handle the basic tasks.

I do (or did) use scaffolding. It's probably a unique situation: I
work for a government agency that has a large number of legacy
datatables which just need maintenance API's stuck onto them to do
CRUD on our intranet.

Some of these monsters have a bajillion fields, and I can erase code a
whole lot faster than I can type it. So, I used "scaffold Monster" all
the time.

I'm sure you're right about most people who do Rails professionally,
though. If I were making standalone websites, like most folks,
scaffolding might be a distraction. I'd do paper prototypes first,
then code as needed in that situation.

I really miss the "old school" scaffolding -- in fact, I may recreate
it and call it something else like scaffold_api or scaffold_crud or
something. Thanks for the scaffold_form_generator, by the way -- it
put back a lot of what I missed the most.

Ron

Ron:

Well, in that case, check out my gem. 
http://scaffoldform.rubyforge.org

It uses the old-style model reflection to build just the form (new, 
edit,
and _form.html.erb) It doesn't generate models or controllers... just 
the
views for the form. I did this for exactly the reason you outlined..
generating a form can be handy.  I basically took the old code from 
Rails
1.2.3 and made it work with 2.0, with a few minor exceptions:  anything 
with
_id is not generated as a field,  created_at and updated_at fields are
skipped,  and anything that's a boolean gets a checkbox instead of a
dropdown.

Maybe that will help.

lol I missed the end of your reply :) Looks like you already are using 
it.
Do you have any suggestions for additions to it?