The verdict on Rails scaffolding

rubyonrails-talk
1

For every tutorial that uses scaffolding, there's an article that says you shouldn't use it in real websites. Supposedly it just serves to "sketch things out quickly", "test database connectivity" and other stuff. Some say you're not even supposed to use it and then edit it later. I don't get why.

What is it about scaffolding that makes it virtually useless? It generates some code; surely I could just expand on it or "fix" what's wrong with it later, right? Apparently not. How is it different from me making my own CRUD base files and copypasting it into every project?

I just don't get it.

2

Feh... pay no mind to the nay-sayers...

I scaffold for proof of concept all the time, then adjust the pieces and parts to fit the "real" application after I'm sure that's what the users were asking for (i.e., after they get to tinker with it in my dev environment).

3

Scaffolding adds things you may or may not want. It's an easy starting point. Sometimes I use it when I need a very simple crud interface. BUT I never use much of the generated views and I'm careful to delete the bits I don't want and change the rest. It also saves a tiny amount of effort to generate the scaffold and do a quick add to my repository. Nothing gets forgotten that way.

I've noticed that a lot of beginners seem to get in trouble with scaffolding. They don't necessarily know what all the pieces generated are or how they fit together, so they don't know what needs changed or what needs deleted. So they end up with effects they don't understand. For beginners I would recommend coding from the ground up by hand until they reach the level where they KNOW what the scaffold will produce and how closely it resembles what they really want.

4

poecide@gmail.com wrote:

Scaffolding adds things you may or may not want. It's an easy starting point. Sometimes I use it when I need a very simple crud interface. BUT I never use much of the generated views and I'm careful to delete the bits I don't want and change the rest. It also saves a tiny amount of effort to generate the scaffold and do a quick add to my repository. Nothing gets forgotten that way.

I've noticed that a lot of beginners seem to get in trouble with scaffolding. They don't necessarily know what all the pieces generated are or how they fit together, so they don't know what needs changed or what needs deleted. So they end up with effects they don't understand. For beginners I would recommend coding from the ground up by hand until they reach the level where they KNOW what the scaffold will produce and how closely it resembles what they really want.

So, the bottom line is that there's nothing fundamentally inept about it, and it's all up to how you actually use it, right?

5

So, the bottom line is that there's nothing fundamentally inept about it, and it's all up to how you actually use it, right? -- Posted viahttp://www.ruby-forum.com/.

With the caveat that Rails beginners may be better off avoiding it until their understanding is better.

6

poecide@gmail.com wrote:

> So, the bottom line is that there's nothing fundamentally inept about > it, and it's all up to how you actually use it, right? > -- With the caveat that Rails beginners may be better off avoiding it until their understanding is better.

I'd capitalize MAY. Other believe that Rails' scaffolding is a very good way for beginners to begin to become familiar with the Rails way of structuring code and tests, of getting working code to begin to become familiar with topics like routing, etc. IMHO, scaffolding can be a very useful learning tool. It's true that not much is typically left when you're 'done'. OTOH, if it helps get you where you're going ...

Best regards, Bill

7

So, the bottom line is that there's nothing fundamentally inept about it, and it's all up to how you actually use it, right?

I would personally agree with that. Your mileage will ALWAYS vary depending on the weather conditions, type of fuel used, people in the car, and cargo inside but ... wait, I got off track there. I tend to use the scaffold to get something up and running and then by the time I am done I have torn it apart and added my own stuff along with getting rid of other stuff.

That is all I really use scaffolding for anymore. When I started, I thought it was the only way to go but now I end up writing more custom code than scaffold stuff, but many times I'll end up scaffolding a resource just to make sure I have my bases covered originally.

8

First, like everything, scaffolding is a tool, a means to an end. It can be useful, but can also be misused. I can't speak for everyone, but I hate scaffolding because it keeps people from writing tests. Scaffolding generates test stubs, but it leaves the controller tests virtually useless. With scaffolding, it's very hard to do test-driven development - instead, you're retrofitting tests to your existing code.

I've found scaffolding to be extremely helpful for beginners learning Rails, but i've seen too many people rely on it to the point where they can't start without one. That worries me, but it's not necessarily the fault of scaffolding.

Now, some aspects of scaffolding used to be pretty bad. The fact that it would iterate over the column names to build table headers was pretty inefficient in a real web app. Some of this has been fixed in recent versions.

I've also found that one of the key reasons people scaffold things after they already know Rails is because having something else build the forms for you is really nice. I hate building forms because it's tedius, so I extracted the original "let's look at your database" scaffolding code from Rails 1.2.3 and made it available as a gem that just builds forms from your tables.

It's available at http://scaffoldform.rubyforge.org

That's just my take on it though.

9

That's a good point, Brian. And your form scaffold is a great idea; even rails' form helpers don't really take the pain out of building forms, but to think that I could bypass all of that with a simple command is mindblowing.

One thing, though: Rails is now 2.2, so that you extracted it from Rails 1.2.3 makes it sound a little too outdated. Do you still use it? Do you know how compatible with the new rails it still is? I could try it, but I'm afraid I'm too much of a newbie to be able to really tell if something's not quite right, even if it seems to work fine.

But that is undoubtedly a godsend.

10

One thing I discovered about scaffolding, even as a starting point, is that if you every want to use nested resources modifying the scaffolding to fit what is needed is more work, and adds more risk, than just building what you need from scratch.

Plus as mentioned you're more likely to write better tests/specs too.

11

One thing I discovered about scaffolding, even as a starting point, is that if you every want to use nested resources modifying the scaffolding to fit what is needed is more work, and adds more risk, than just building what you need from scratch.

That's actually a fantastic point I was running into for a while until I decided to clean out the whole controller I had scaffolded and just wrote it myself and fixed all of the ridiculous problems I had created for myself.

There is also nothing quite as satisfying to see the cleanness of a controller after you have built it from scratch.

Plus as mentioned you're more likely to write better tests/specs too.

Anyone willing to teach me how to use Rspec? Anyone? Bueller?

12

Meh, I'll teach you RSpec if you want, but I''m a bigger fan of test::unit. Find me on IRC - hoganbp

13

Ralph:

It works fine. I just stole the generation code from Rails 1.2.3 but it works fine in Rails 2.x - I have a few things I might want to change as it goes forward, but I keep my stuff in pretty good shape - if it's deprecated I'll push a final release that says so in the readme :slight_smile:

I'm always looking for suggestions too.

14

Hi --

For every tutorial that uses scaffolding, there's an article that says you shouldn't use it in real websites. Supposedly it just serves to "sketch things out quickly", "test database connectivity" and other stuff. Some say you're not even supposed to use it and then edit it later. I don't get why.

What is it about scaffolding that makes it virtually useless? It generates some code; surely I could just expand on it or "fix" what's wrong with it later, right? Apparently not. How is it different from me making my own CRUD base files and copypasting it into every project?

I just don't get it.

Here are a few problems I've seen, and continue to see, with the scaffolding.

It leads people to think that Rails is going to be dead easy, and then they get frustrated or disappointed when it turns out that developing a Rails app is real development and real programming.

Although it pertains usually to the beginning stages of an application, it does not play well with the beginning stages of learning Rails. It presents way, way too much code to be useful to beginners. The controller files can be a useful "cheat-sheet" for REST idioms, but only once the basic techniques and principles are understood.

As you point out, the scaffolding makes you tweak things and remove wrong things, instead of developing what you actually need. It turns development into sculpture (remove everything that isn't your application!), and introduces anxieties about whether you're doing something wrong because you're changing something fundamental about the scaffold code, etc.

It presents a very rigid and specific context for the idea of a "resource" (in the REST sense), which then impedes people from gaining a broader understanding of what a resource can be. For more on this problem, see:

http://dablog.rubypal.com/2008/3/23/splitting-hairs-over-resource http://dablog.rubypal.com/2008/4/24/splitting-hairs-over-resource-part-2

I agree with the point that others have made that if you know exactly what the scaffolding provides, and you've got a situation where that's exactly what you need, there's no harm in using it. If those particular boilerplate files happen to coincide with what you want, that's great. Otherwise, I'd avoid it. There's no reason to give it first refusal of your development space, just because it's there.

David

15

Agreed, nice post there... The only thing i'd add to that, is that as a Rails beginner-becoming-intermediate, I actually really like the fact that you can get something up relatively quickly and then start hacking away at it to create an app... I'd also add that unless you really understand what's happening in terms of REST, etc. then it's near impossible to effectively build a respectable app... I've had a few moments of frustration/disappointment since I've created my first scaffold, but as long as you stay the course, and have some programming knowledge, it all makes perfect sense eventually...

16

Hi --

17

Thanks David... I'm pretty familiar with that stuff already thankfully... but cheers for the info... Right now, i'm coming to grips with what plugins are out there, which ones are the most common/ popular, and how are they best used... I don't want to be relying on plugins too much, but then again I don't want to have to spend time doing something that's already been done...

thanks for the link...

18

Ah, that scratched an itch for me--thanks for posting that.

Cheers,

-Roy

19

Thanks David - great article - most illuminating... Dave