WEBVTT
Kind: captions
Language: en

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Now that we've created a serializer for
our app we can go ahead and add the post

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functionality to our API view

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Start by
opening up the views dot py file and

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we're going to add a couple more imports to
the top of the file so the first one

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we're going to add is the status import
from the rest framework so let's type

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from rest framework import status the
second input we're going to add is the

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serializers module that we created in
the previous video so type from profiles

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API import serializers

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The status object
from the rest framework is a list of

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handy HTTP status codes that you can use
when returning responses from your API

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so we're going to be using these status
codes in our post in our post function

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handler

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These serializers is the
serializer module that we created in our

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profiles API project we're going to use
this to tell our API view what data to

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expect when making post put and patch
requests to our API so we set the

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sterilizer by typing serializer
underscore class equals serializers dot

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hello serializer

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This configures our API
view to have the serializer class that

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we created in the previous video so this
says whenever you're making a or

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whenever you're sending a post put or
patch request expect an input with name

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and we're going to validate that input
to a maximum length of 10

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Okay so now we

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can add the post function to our API
view create a new function under the get

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function that we created previously and
type def post self comma request and then

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we'll add the doc string create a hello
message with our name and this is what

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we're going to do when we receive a post
request to our hello API

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So what we'll

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do first is we'll retrieve the
serializer and pass in the data that was

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sent in the request so type serializer
equals self dot serializer

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underscore class and then data equals
request dot data

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The self dot

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serializer class function is a function
that comes with the API view that

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retrieves the configured serializer
class for our view so it's the

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standard way that you should retrieve
the serializer class when working with

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serializers in a view

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The second part
assigns the data so when you make a post

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request to our API view the data gets
passed in as request dot data so it is

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part of the request object that's passed
to our post request we assign this data

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to our serializer class and then we
create a new variable for our serializer

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class called serializer

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So next we can
go ahead and validate this serializer

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so I mentioned previously that the
Django rest framework serializers

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provide the functionality to validate
the input so that is ensuring that the

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input is valid as per the specification
of our serializer fields in our case

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we're going to be validating that the
name is no longer than 10 characters the

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way you validate a serializer is you
call it is valid class so you can type

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if serializer dot is underscore valid
and then if it is valid we'll perform the

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logic that we want to do if the
serializer is valid so what we want to do

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is retrieve the name field from the
validated data so type name equals

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serializer dot validated data
dot get name

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this retrieves the name

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field that we defined and you can
retrieve any field that you define in

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your serializer this way

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Okay so now
that we have it we're going to create a

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new message and this message we're just
going to return a message from our API

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that contains the name that was passed
in the post request just to demonstrate

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how the post request works so let's
create a message variable called message

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equals and we're going to use the F
string functionality here to insert the

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name into a string so we'll type a
string that says hello and then the way

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you insert variables into a string if
you put this F before the string you can

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simply use the braces like this to
insert a variable from your code into

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the string so we're going to insert the
name variable

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Okay then after we have

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this variable here message we're going
to return this as a response so type

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return response and then pass in a
dictionary to the response and we're

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going to give it the key message and then
we're going to pass in the message variable

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okay that's all good if the input is
valid but what should happen if the

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input is not valid well we're going to
return a HTTP 400 bad request

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response so in the if
statement type else : and then return

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and return a response and then in the
response we're going to pass in the

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errors that were generated by the
serializer so if you type serializer dot

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errors this will give you a dictionary
of all the errors based on the

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validation rules that were applied to
the serializer so it's a good idea to

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return this so the person that's using
the API knows what went wrong when they

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tried to submit an invalid response

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Okay
by default the response returns HTTP 200

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okay request now since this was an error
we need to change this to a 400 bad

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request so we return the standard error
response code for this type of error in

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an API so let's actually
break this down on to separate lines

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here and let's add a second parameter
called status equals status dot and then

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in all capitals HTTP 400 bad request

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Now
you could pass in just an integer 400

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here however it's good to use this
status object here to get it because

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then you can easily see what the request
means when you're looking at the code so

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we know this 400 bad request means there
was a bad request made to our API

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okay so save that file and that's how
you add the post functionality to your

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API view