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We've done most of what we can do outside of an app, so let's make our first app.
Django projects contain multiple Django apps. Each app generally encompasses a specific area of functionality.
python manage.py startapp creates the skeleton of an app including the views, models, and tests files.
INSTALLED_APPS is a list of all apps that Django should consider installed and active for the current project. These apps will be used to find templates, tests, models, and migrations.
TIME_ZONE is the setting for what time zone your server is running in. The docs explain a little more and there's a list of time zones you can use.
You're probably wondering what the heck
I'm talking about when I say app.
0:00
Didn't we just make an app?
0:03
Haven't we been working
on an app all along?
0:05
Well, yes and no.
0:07
Django has long had this
concept of plugable apps.
0:10
Let's break those two words down though.
0:13
An app is a self contained bit of
functionality like a system for
0:15
comments or a way to reference
files from Google Drive.
0:18
So for example, if we end up building
a solid learning library tool,
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one that other people could easily use and
adapt to their own needs, we might release
0:24
it as an app for other Django nuts to
install into their projects and use.
0:28
And that brings us to the other word,
pluggable, or Django apps that can be
0:32
moved from project to project usually by
installing them from the Cheese Shop.
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Since these apps can be plugged into your
project we say that they're plugable.
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So a single project is made
up of usually multiple apps.
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This is a good thing because it means you
often don't have to build a large part
0:48
of your project.
0:51
And who doesn't like extra time off?
0:52
So to create an app we're gonna
use the manage.piescript again.
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This time we are gonna use
the start app command,
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and the name of the app
that we want to create.
1:00
App names are usually the plural
form of the main model
1:03
that your app is going to be about.
1:07
I like this convention because it
means that you need to have a bit more
1:09
thought put into your work
before you just jump in.
1:12
Normally we're like yeah
let's go do something but
1:15
often it's a really good idea
to plan things out a little bit.
1:17
You can of course rename things
later if you change your mind.
1:20
So, our main model is going to be for
a course, so let's name the app, courses.
1:24
So we're gonna kill the server there.
1:30
Pythonmanage.py.
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Start app.
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Courses.
1:37
Again, no feedback.
1:39
That's cool that's fine.
1:41
Let's run our server again so
we don't forget about it.
1:43
Okay, come over here and
refresh our file tree, and
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now we see we have a courses directory.
1:52
So lets look in there.
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Okay, so its at the same level as our
1:56
learning site stub all of our apps
are going to live next to each other.
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If we had more apps.
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Right now we only have one.
2:07
And its not really surprising
its named courses that's what
2:08
we told it to be called.
2:11
Inside of there we have an admin.py we
have models.py, test.py, and views.py.
2:12
We also have a folder called migrations
currently though its empty it just has
2:18
the standard init.py in there.
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Those init.pi files, by the way,
if you don't already know,
2:24
mark a directory as being a Python module,
they're what let us do imports and
2:27
things like that with files that
are inside of these directories.
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Most of the time, they are 100% blank.
2:36
We'll explore all of these files in
the rest of this course, but for
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now, let's just get the app
added into our project.
2:41
We do that by opening up settings.py,
and if you hear
2:45
me say something about like our settings
file, this is what I'm talking about.
2:51
This file has a lot of stuff in it, and
we don't need to worry about most of it.
2:54
About half way down though there
is a tuple called installed apps,
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and this thing we need to edit.
3:04
So down here at the bottom,
after all of Django's apps,
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we're going to add courses and
we're going to end it with a comma,
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because it's a good chance we're
going to add more apps later.
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Even if you don't, it's still a good
idea to always add that comma.
3:18
Trailing commas are a pretty good habit to
pick up when you're writing Python, but
3:22
I am going to apologize
now if they cause you just
3:25
all sorts of head aches in other
languages like JavaScript.
3:27
Okay, one more thing
that I like to change is,
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if we come down just a little bit farther,
you will see
3:34
A, there it is, time zone.
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So the time zones are a little picky.
3:44
They are a specific set of time zones.
3:46
They're a fairly standard set,
but you can't just put in,
3:50
like, PST for Pacific Standard Time.
3:53
I'll put a link in the teacher notes for
all the possible timezones.
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I'm gonna change mine since
I'm on the west coast.
4:00
I'm gonna change this
to America/Los_Angeles.
4:02
All right, if you want to
change the timezone, go for it.
4:05
Change it to whatever your local timezone
is and this way if we're using dates or
4:09
times in our project, they'll be correct.
4:13
It probably feels like I stopped just
when things got interesting, huh?
4:16
I wanna give you a little bit of time
to let projects and apps settle in.
4:19
Also, this just means the next
stage will be even more exciting.
4:22
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