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You have completed Introduction to Ruby on Rails 7!
You have completed Introduction to Ruby on Rails 7!
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Link each user to their Linktree pages using Active Record associations. You’ll see how belongs_to and has_many relationships keep your data organized and accessible.
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Okay, so in this video, we want to add
relations between the user and the tree.
0:00
Now, what does this mean?
0:04
Well, first of all, why are we doing this?
0:06
Well, the reason that we are doing this is
because any other user that is signed in
0:08
can delete my user's tree.
0:13
And I'm going to show you that in action.
0:14
So I'm gonna create a tree add light mode,
and
0:16
then what I'm gonna do is copy this link,
go into Edge.
0:19
And this is a different browser,
because if you use the same browser,
0:22
then it's not gonna work because
you'll already be signed in.
0:26
Go to the URL port 3000, then I'm just
0:30
gonna sign up with a different email,
0:35
then add my password 123456-,
0:40
2456, create account.
0:45
And then what we can do is
actually go to the URL, Enter and
0:48
we should be able to destroy it.
0:53
So let's click Delete my tree and
as you can see,
0:55
a different user just deleted this tree.
0:58
So we need to fix this problem.
1:00
Now, one quick, simple way to do it
is to just go to the app folder,
1:02
then go to Views,
then go to Trees and show.
1:07
And then what you want to do is uncomment
this line, you won't have it there, but
1:11
just write this line.
1:15
If the current user.id is
equal to the app tree.userid,
1:17
then show the delete button because
that means that the user is validated.
1:21
Now, you won't actually have
the tree.userid field, so
1:26
I'm gonna show you how to do that now.
1:29
So you need to go to trees form, and
then what you need to do, I'm just gonna
1:32
scroll up to wherever it is, I'm gonna
find it, user underscore id, there we go.
1:37
And here is the input field
where the user id is.
1:43
What you need to do is add
value current user.id.
1:46
That way this will
automatically be filled and
1:50
then you can match it against tree.userid.
1:53
You can match the tree user ID against
your current ID to see if it works.
1:56
Now, this is one way to do it,
and as you can see,
2:00
if I refresh, I can no longer delete it.
2:03
But if I make another tree and
then add the Instagram and all this,
2:05
and then I press next and then I go
into Edge and I try and delete it,
2:10
it's not gonna work.
2:15
No, it actually gives us an undefined
method id and this is really important.
2:17
The reason it gives us this error
is because we're not signed in.
2:21
So what we need to do is to make
sure we're actually signed in.
2:24
So we're gonna say if
user underscore signed
2:28
underscore in question mark and then end.
2:33
That way we will not get this error.
2:37
As you can see,
I'm on a different account, but
2:41
I cannot actually see the delete or
edit buttons, so that's good.
2:44
Let's start, now,
this video is about adding relations.
2:48
So what we're gonna do is
go to app models tree and
2:51
what we have to do is say
belongs underscore to the user.
2:56
What this means is that this
tree belongs to the user.
3:01
And then what we have to do in the user
model is say has underscore one tree.
3:05
Now what you can also do
is say has many trees.
3:13
But I don't personally like to do that as
I don't think a user should be allowed
3:18
more than one link tree.
3:22
So I'm gonna say has one tree and
this is belongs to the user, so perfect.
3:23
Now that we've done that, we can
access things like current user.tree.
3:31
So what I'm gonna do is exit edge and
3:35
what we're going to do is go to
the homepage of our application.
3:38
Then what we want to do is create
a link to our personal tree, so
3:43
let's do that now, go to Views-Home-index.
3:48
What we're going to do is
say link to embedded Ruby,
3:52
link to viewmytree and
then we're gonna say
3:57
current_user.tree and
I believe that might be enough.
4:01
And we go viewmytree and it does work.
4:07
But what we have to do also
is just say if current_user.
4:10
This is another way of saying if
the user is signed in, okay, so
4:14
perfect, that button works.
4:18
So now that we've added the relationships
between the user and the tree,
4:20
we can actually make sure that
our application is safe and so
4:24
another user cannot delete our tree.
4:27
In the next video, we're going to
add a new page called pricing.
4:29
It's purely going to be for
4:33
stylish reasons of the website
doesn't have any functionality at all.
4:34
But I'm just gonna show you
how to create it just so
4:38
we get some more practice
with creating pages.
4:40
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