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You have completed Introduction to Ruby on Rails 7!
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Speed up development with Rails’ powerful scaffolding tool. You’ll learn how to generate full CRUD (Create, Read, Update, Delete) functionality in just a few simple commands, and discover how database migrations keep your data model in sync.
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Okay, so in this video I'm going to share
with you the feature that made me fall in
0:01
love with Rails, and this is scaffolding.
0:05
Scaffolding allows you to 10x your
pace by normal coding, but with Rails,
0:07
basically, it's a command that
lets you create a CRUD layout.
0:13
CRUD stands for create,
read, update, destroy.
0:18
Imagine we have a blog post, the four
actions that we can deal with this blog
0:21
post, we can create it, we can read it,
we can update it, or we can destroy it.
0:25
Rails allows us to achieve
this in one single command so
0:30
we can create a blog post with
the title and description.
0:33
With one single command,
we can create, read, update,
0:37
and destroy it,
that's my best way to explain scaffolding.
0:40
So let's give this a go.
0:43
What we're going to do is go into a
command prompt, I'm gonna stop the server
0:44
from the last episode, and
I'm going to create a new command.
0:47
So it's gonna be called Rails new scaff,
I mean Rails g scaffold,
0:50
we're gonna call it tree and
this is the name of our scaffold.
0:55
Now after you've set the name
of your scaffold in the command,
1:00
don't hit Enter yet.
1:03
After you've set the name of
the scaffold in your command,
1:04
you have to set all of
the attributes in your scaffold.
1:07
Now in our particular case,
these are the attributes that we want.
1:09
You can add more in the future so
it's not a big deal right now, but
1:13
it is easier to add them now,
not in the future.
1:17
And so for starters,
we're just going to add these six.
1:20
We're gonna say name, and you also have
to add the type that you want it to be.
1:23
So name is a string,
if you don't know your programming types,
1:27
well here's the lowdown.
1:31
String means characters,
letters, and numbers.
1:32
The next attribute is going
to be called X string for
1:36
Twitter, then Instagram string for
Instagram, then YouTube string.
1:39
Because remember, we're creating
link tree, so we want the user to be
1:44
able to upload their URL and
their social medias into these attributes.
1:49
User_id integer and
1:54
then style string.
1:58
Now we're gonna hit Enter
on this command and
2:02
lots of crazy things are going to happen.
2:04
Millions, well not millions, but
lots of files are going to be created, so
2:06
let's hit Enter and see the madness.
2:09
This is the most exciting command and
you're going to be amazed after this.
2:12
Unless you've already seen it before,
in which case you'll still be amazed.
2:16
Now as you can see,
I created lots of files.
2:22
And the next command that we have to run
is a command that you always have to
2:24
run after you run this command,
and it's called rails db migrate,
2:29
what this does is migrate the pending
migrations to the database.
2:33
We're gonna run it, and then I'll
explain a little bit more to you because
2:37
it's very, extremely vital, important,
I cannot stress this enough.
2:41
But let's just wait for
the command to run as you can see,
2:45
it says create table trees.
2:48
Now let's go into VS code and check this,
so where did it create this table?
2:50
Well if we go into the db folder,
we see the schema rb,
2:56
this was just created because it's
the first time we ran a migration.
2:59
Then we see this create table trees,
this is the scaffold we just created.
3:04
These two attributes are default and
they come with every scaffold, and
3:08
here are the other six
that we added beforehand.
3:13
Now I haven't even shown you the magic of
this scaffold, but I'm gonna show you now.
3:16
So what we need to do is go into app
assets or no, not assets, we need to go
3:21
into views index, and what we need to do
is to create a new link to the scaffold.
3:26
As you can see if we go into controllers,
it created a new controller,
3:31
it created a new folder, and it created
a new model as well, tree model.
3:35
It created all of the necessary things for
new page, new pages, in fact.
3:40
So what we're gonna do is create
a link to that page, so let's do that.
3:45
We're going to say embedded Ruby,
which means we're using Ruby now.
3:49
So look at it, so we're saying smaller
than sign, then percentage sign,
3:53
then equal sign.
3:57
If you don't add the equal sign,
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then that means we're not going to render
what's inside of the embedded Ruby.
4:00
This is good for
4:03
if statements, because you don't want
to render an if step onto the page.
4:04
But we do want to render the link so
we're going to use an equal sign and
4:08
we're going to say link to,
I'm gonna say new tree.
4:12
Now is that good, well, no, that's not
good because we just have the link, but
4:17
we don't know where to actually go.
4:21
So let's add where we actually want to go,
so we're gonna to say new_tree.
4:22
Now is that good, no, because after
every route, this is the route.
4:27
We need to add underscore path,
now, where did I find this route,
4:31
how do I know that this new tree?
4:36
Well there's a place where you
can find all of the routes,
4:38
and I'm going to show
you after this video.
4:41
So let's save this file, and
then let's go to the browser and
4:43
then let's refresh the page and
let's see what happens.
4:46
And I forgot to start the server
because I'm a noob, I'm just joking.
4:51
I've been using this framework for
a few years now, I know what I'm doing,
4:54
please don't attack me.
4:57
Anyway, start the Rail server and
then refresh.
4:58
As you can see, we have a link here,
let's press it.
5:03
As you can see, we get a new page we have
not seen before, we did not code this.
5:09
We did not code this, all we did
was run a simple command up here.
5:13
It created all those files, and
look, I can add a new tree,
5:17
Malachi Asgharian is the name,
that's my name.
5:21
New X, I'll just add the Instagram
link for all of the links and
5:24
then user three style.
5:28
We'll just create a tree and
as you can see, it's created and
5:30
saved to the database.
5:34
This is inside of the database,
it's not going to be destroyed ever,
5:36
unless you click destroy, obviously.
5:39
So let's click destroy, why not?
5:41
No, before we do that let's edit it so
I can show you.
5:43
We just edit it, and
then we click update and it updates.
5:46
Everyone can see this,
everyone can see it and
5:49
everyone can destroy it or delete it,
destroy stands for delete.
5:53
So we can press show and then delete,
this is the power of Rails.
5:58
This is the power of scaffolding,
it's extremely cool.
6:04
This page, these pages, these four pages
were created just from that one command,
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that's why I like this so much.
6:12
This is the beginning
of our link tree clone.
6:14
In the next video,
I'm gonna teach you about Rail's roots, so
6:17
let's get onto that now.
6:20
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