WEBVTT
Kind: captions
Language: en

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The first step of creating our user
profile feed API is to create a new

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Django model for storing the user
profile feed items in the database so

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open up the project in the atom editor
and open up the models dot py file we're

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going to start by adding a new import
into the top of the file and that's

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going to be the settings import from the
Django dot conf module so type from Django

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dot conf import settings this is used to
retrieve settings from our settings dot

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py file in the project settings of our
Django project the particular setting

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that we're going to retrieve is this
author user model and I'm going to show

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you why we need to retrieve that in a
moment so at the bottom of our models

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dot py file let's create a new model and
we're going to call our model class profile

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feed item and we're going to base it from
models dot model and at the dock string

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profile status update so this is going
to be the model we use to allow users to

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store status updates in the system so
every time they create a new update it's

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going to create a new profile feed item
object and associate that object with

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the user that created it the way you
link models to other models in Django is

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you use what's called a foreign key when
you use the foreign key field it sets up

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a foreign key relationship in the
database to a remote model

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the benefit of doing this is that it
allows you to ensure that the integrity

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of the database is maintained so you can
never create a profile feed item for a

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user profile that doesn't exist so let's
go ahead and add our user profile field

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to our profile feed item type user
underscore profile equals models dot

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foreign key
and the first argument of a foreign key

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field in models is the name of the model
that is the remote model for this

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foreign key so which model do we want to
set a relationship up from this user

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profile field to a remote model so
we're going to set it up to the user

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profile model now you could specify this
as a string as the first argument of the

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foreign key however when you're
referencing the auth user model in

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Django it's best practice to retrieve
this from the settings dot py

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configuration the reason for this is
that you may decide that you want to

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switch out this user profile model as
our default authentication model and you

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want to switch it back to the Django
default model if you hard-coded the

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name of the model here then you would
have to go through and manually update

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all of the foreign keys where you
hard-coded that if you were to switch

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out the default user model

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so what we do instead is we've reference it by typing

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settings dot auth user model

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and what this will do is it will retrieve the value

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from the author user model setting in
our settings dot py file so if we ever

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swap this auth user model to a
different model then the relationships

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will automatically be updated without us
having to go through and manually change

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it everywhere that we've referenced it
in our models dot py file ok so the

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second argument we need to provide is
the on delete argument so type on delete

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equals models dot cascade

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now what the on delete does is it tells Django or it

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tells the database what to do if the
remote field is deleted so we have user

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we have profile feed items in our
database and each one of them has a user

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profile associated with it now because
there's a foreign key Association the

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database needs to know what happens if
you remove a user profile what should

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happen to the profile feed items
that are associated with it and the way you

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do that is by specifying this on delete
so there are different things that you

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can set on delete one of them is cascade
and what that does is it says basically

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cascade the changes down through all the
related fields so if you have user

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profile feed items associated to a user
profile and you remove that profile then

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it will cascade the change down and
remove the associated feed items from

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that user

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another option is to set that
field as null so what it would do is

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models dot set null would set the value
of the user profile to null if the

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remote user profile is deleted

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now I think it's better to cascade in this

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case because if a user wants to delete
their profile then we can assume that

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they also want to delete all the feed
items that are associated with their

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profile

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alright so the next field that
we're going to add is the status text

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and the status text is going to be used
to contain the text of the feed update

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so type status underscore text equals
models dot

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char field max length equals 255

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so we're going to set a char field here which

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is a standard character field and allows
us to put in a text input up to 255

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characters long

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next we're going to add a created on field so type created

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underscore on equals models dot
date time field and then set the

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argument auto now add equals true and
what this does is it says every time we

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create a new feed item automatically add
the date time stamp that the item was

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created so we don't need to manually set
this when we're creating the item it will

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automatically be set to the current time
because of this auto now add parameter

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okay finally we're going to add a string
representation of our model so that is

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to tell Python what to do when we
convert a model instance into a string

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so we're going to type def underscore
underscore

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str underscore underscore open brackets
self :

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and we'll write the doc string return
the model as a string and then we'll

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just do return self dot status
underscore text so when we convert this

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to a string we want to see the status
text value that is associated to the

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model

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okay so that's how you create a
profile feed item model in django make

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sure you save the file and i'll see you
in the next video