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Django has a built-in server that we can use during development.
python manage.py runserver 0.0.0.0:8000 will run the server for Workspaces. On your own computer, you probably don't need the 0.0.0.0:8000 part.
python manage.py migrate will apply all pending migrations from all apps. More on apps later.
What are migrations?
Migrations are a way of moving a database from one design, a specific set of tables and columns, to a new one. Migrations are reversible, too. The fact that they can be done backwards and forwards is what gives them their name.
[MUSIC] 0:00 >> Okay, so you have Django installed, and you've created a project. 0:05 You're well on your way to becoming a Djangonaut. 0:08 Yeah, that's the collective noun for people that use Django. 0:10 Okay, enough about silly nouns, let's go see how to get Django server up and 0:13 running so we can get to the fun part of building an app. 0:16 So, remember the manage.py file? 0:19 The one that I said would be our main control script, our entry point for 0:21 our project? 0:26 Well, we're going to use it. 0:27 If you did the Flask courses, you'll remember that we had to tell Flask 0:29 to listen for requests on 0.0.0 in port 8000. 0:32 Well we have to do that with Django too. 0:36 If you didn't take the Flask courses we have to do this so 0:38 that Django can talk through our work spaces server to the actual internet so 0:41 that we can see it from wherever we are are on the internet. 0:46 Let's go ahead and run this. 0:50 So what we're gonna do is we're gonna do, first we gotta get in there. 0:51 cd learning_site/. 0:53 I'm in the same directory as manage.py. 0:56 So, I'm gonna do python manage.py and then I'm gonna do run server. 1:00 And the address I'm gonna go to is 0.0.0.0:8000. 1:06 And I hit Return, and you're gonna see a bunch of stuff run through here. 1:14 Don't worry about this too much right now, we'll get back to it in a minute. 1:18 And then I'm gonna come up here to the Preview icon, and I'm gonna click 8000. 1:21 Check that out. 1:25 I've got a Django powered page telling me everything is good. 1:27 That's awesome, wonderful, glad to have that. 1:32 So let's go back. 1:35 And if we look here in our output we have this, you have unapplied migrations. 1:37 What is that? 1:42 What is that about? 1:43 That's really weird. 1:44 So, what this is, is Django comes with some migrations. 1:45 So migrations are a way of moving your database from one design to another. 1:52 You're moving, you're changing the structure, the organization or 1:57 the data in the database from one configuration to another. 2:00 Often you'll find that your table now needs a new column 2:05 to handle an extra little bit of data. 2:08 Or maybe you want to store a preferred name alongside the legal name that you've 2:10 already collected. 2:13 You'd add this column with a migration. 2:14 Which moves the table from one design into the other. 2:17 You can reverse this process too, and remove the column. 2:20 Since you're moving back and forth, that's what gives it the name migration. 2:23 So, we're gonna kill our server here. 2:28 I can do that with Ctrl+C. 2:30 And we're gonna run our migrations. 2:33 So. 2:36 We do python manage.py migrate. 2:37 Just like it says to do right here. 2:40 We follow the instructions that run server gives us. 2:43 It prints out a whole bunch of stuff. 2:46 And we can see that it found a few different operations and 2:48 it's running migrations for I think four different apps. 2:53 So, migrations, I said, were about the database. 2:57 We didn't set up a database. 3:00 Well, Django comes with one. 3:02 So, let's refresh. 3:05 And if we look here, then we have this db.sqlite3. 3:08 Django automatically creates this database for 3:12 us if we don't tell it something else to do. 3:14 So we have this automatically. 3:17 Now this is SQLite. 3:18 This is fine for testing your idea or playing around in. 3:19 If you get really serious, you're gonna wanna move to a real database, 3:24 you're wanna move to MySQL or Postgres, and 3:26 you definitely wanna use one of those two, or one of the other wonderful databases 3:29 that are out there before you go live on the internet and have users. 3:33 Let's try doing our run server again. 3:39 Push Up a couple of times. 3:42 And this time we don't get any error messages. 3:43 And if we come over here and 3:46 refresh our site, it still loads just like it's supposed to. 3:47 If you didn't quite get what migrations are about, don't worry. 3:52 We're gonna be creating and running more of them later on. 3:55 But, the first thing you have to do with any new technology is make your own 3:57 Hello World. 4:01 So, let's do that next. 4:02
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