FastAPI for Beginners: Build APIs in Python - Full Course

[00:00:00]Fast API makes it quicker and  easier to develop API's with Python.   Tommy will show you how it works in this course,  his first API Crash Course. First API is a modern,   fast and iperformance web framework for  building API's with Python. In this video,   I will show you how you need to get started  working with fast API. First API also has a very   good and easy to follow documentation, which I can  also recommend. And it is also a great framework   for building web applications with Python. During  this tutorial, there are some tips on keynotes   that you might want to take down. But I already  did this for you. So I made a fast API cheat sheet   in which you can download for free using the  link in the description below. And if you'd   like more tutorials, ideas, don't forget to  check out my channel as Cody told me, where   I teach more on Python, and web development in  general. The only requirement for this tutorial   is that you have the basic knowledge of Python,  and you have Python installed on your computer   with a minimum version of 3.6 or higher. Have you  noticed said let's dive straight into this video.   So the first thing we're going to be talking  about is how we're going to install fast API.   Now to install fast API on your computer, your  laptop is very easy. Because first API is a Python   framework, we're gonna use the Python package  manager, which is Pip. So you can just open   your command prompt if you're on a Windows,  whether you're on a Mac, open your terminal,   and we can just type Python, I think m pip install  bust API. Now it's very easy to just do command   line you need to install fast API. You can also  do Dinamo, we like peeping so fast CPI. Or if   you're on a Mac, you can do PIP three install for  CPI, just the normal installation command lines.   So I just like using Python, by free, just  personally, but you can install it anyways. So   I that is running. And as you can see  it says requirement already satisfied.   Now if you walk with Python, you know that this  means that I already have this particular library   installed on my computer. So because I have it  installed, it's not going to go ahead and install   that again. Let me just type CLS to clear that  up. So what that did was it install fast API. So   if you do a fast API, you stored it, you go ahead  and download some files or not just only fast API,   some other stuff that you're going to use later,  like typing or some other libraries, it's going to   install that alone. And there's one more thing  we need to install to let's say, Pip, install   you you'll recall. Now the reason why we say p  p. So you recall this recall is what we're going   to use to run our web server. Now, if you work  with other libraries, like for example, Django,   you know that Django, you don't need to install  any external team to run it or your web server.   Once you just type a command line, if you have  Django installed is going to run into a web   server. But fast API is totally different. Because  working with fast API is a very light library. So   you need like an external library just to run  that file on the web server. So this UV con is   going to allow us to run our first API project  or file on the web server. Once I press enter,   now, I should also be expecting a requirement  already satisfied, because I have this particular   library installed. As you can see, it tells me  requirement already satisfied, the ledgers closed   our proposal. The next thing I want to do now,  the first thing before I started this, I already   gave it to my folder by came to this directory,  and then I created a Python file name my api.py.   And in my Visual Studio code, I already open  up the file. Yeah, my api.py. So this is the   file we're going to create in our API's  are running everything we're gonna do.   What I just want to do is to copy this particular  directory for me to my command prompt and CD into   that. If I press dir, right now, you can see  that I have the file, just to make sure that   we're in that particular directory. And  now that I know I'm in that directory,   let's just go ahead and create our first API.  Now the reason I just opt into this directory   is just simply because when I want to run these  on our locals on our web server later, I need   to make sure I am in that particular directory.  So I can run the file in that directory. So Oh,   this is going to make sense later. But let's  just go into Visual Studio. Now, first of all,   let's just import past API. So  we can just do import past API.   And if we save this and come into our  command line and run that Python, my API spy,   so if that runs without any error, or anything  like that, so as you can see it doesn't give   us any early response does just because there  is that's the teller, the first step has been   installed successfully. So let's just close that.  Now let's just go ahead and create our first API.   Now, well, we need to do to create our first  API, we'll say from first API, import past API.   Exactly. So this is just import first API, like  an object to work when you use this object,   or an instance of this object to create our API's  later. So now that we have this is imported,   we're gonna set up is equals to fast API. We're  taking it from this first API, which we imported   to our creating like an instance of the first  API object, so we can assess this later. Now this   object, it has plenty attributes like the get,  let me do let me go into that now by just some   other things that we're going to use to create our  API later. So now that we have that created, what   we want to do is to create an endpoint. Now let me  explain what an endpoint is, to an endpoint is one   end of a communication channel. So that's why so  complicated. But what that just means for an API,   an endpoint in a URL, so let's say we  have a URL like on our local hosts, slash,   delete user. list if a user so for this particular  URL, the endpoint is this delete user. So this   is like the path in a normal URL, we call it the  path. Let's say we have something like amazon.com.   And then we have something that Yeah, just  delete user or something like create user.   So this is we can say this is our endpoint in  a normal URL. This is the path, we're dealing   with API. This is like our endpoint to just have  that at the back of your mind on each endpoint,   where you're specifying your URLs do  my like, perform different operations.   So my just get a particular information,  a particular data store might be too late,   for example, this great user, the endpoint is  self explanatory is creating a new user. So   that means he will have to post some data to that  endpoint, so we can create a new user. So again,   you're gonna understand this when we get straight  into it. And there are different type of endpoint   methods, body cones, there, there are lots  there are not too much, but they are a lot,   but the core ones get not this get, we have posts,  we have routes. And then we have delete, let me   just explain this quickly. So the get is used to  just get an information or return on information   just to get or return a data or something like  that. And then of course, this is just to create   something new, and put it like that with something  new, or create like a new object in the database.   And therefore put this port is used to update  a data or to update something in a particular   object. So all these again, you are going to  understand when we are putting all these in all   this practically, for updating on Delete is self  explanatory, is just used to delete something.   So as I said, these gets used just to get or  return data or information post is to create   something new or just to add something new input  is used to update something that already exists   in that particular database, and delete it  just to delete like a data from a database   or something like that. So now that we have all  these known, I already understand all these,   let's just go straight into creating the route  HIV, the real API. Now for me to create a new API,   I'm going to do at the Add sign up dot get. And  as you can see, for this API, I'm using Git,   and according to the explanation I did like  a few minutes ago, it shows that I want to   return on information or we just want  to show an information. So if I want to,   like do something else, like posts, put delete,  we're also gonna do all that later in this video.   But let's start with get laughter You say app dot  get a note that this app is getting from the first   API instance, which is what we imported, say app  dot get. And then we're opening a bracket to the   current output slash. So this is our endpoint, our  API to the home or right slash, it means our own   and our own can be like, what what we show when  we just come to our own page, like google.com   does the homepage. So whatever our domain is,  does Just our own page is something like slash,   Bessie like delete. So that is another like  URL, it can be google.com slash delete. But now   this is just the homepage just to make sure  you get that correctly. But now that we have   that we're gonna have a new function, let's name  this index, our own or anything wants to name it.   And the no Ledger's return particular  data, series name, ciphers data.   So what this is doing now, as we say we are taking  from the app, which is also taken from the past   API object hours in a get method. And the endpoint  you specified is the home page or the home URL.   And then under that, we're just going to have a  new function, we can name this anything we want,   what we just do is to return this particular data.  Now, this is just a dummy data that we just input.   But later on, I'm going to show you how  you're going to use it as a Python dictionary.   And yeah, normally when we're returning  data to be written in Python, your response.   This API first API uses JSON, but later on, so I'm  going to show you how to use a Python dictionary   and automatically converted to JSON data. But  for now, this is just a normal JSON data is being   returned. Let's save this particular file. And  first run this and really see what we are doing   on our web server. That's when UV call comes in.  But let's go back to our command prompt. First,   to be able to run these, let's just make sure that  we're in the directory of this particular file.   And to make sure we just press dir,  and then we see our file does good.   Now for us to run these we need to press after it  is the first one we need to add is the name of the   file, which is my api.py. The second one is the  name of the variable you use, most of the time,   it's always up. And then there's basically two  things but ledger says we know that Ledger's roll   this on the web server, what I'm going  to do now I'm going to say yuvika   gonna leave a space. And I'm gonna say my API,  which is the name of the file, but now we don't   write about api.py, we just write only the name  of the file, not with the file extension. And then   we'll put a colon, I'll say up. And this is coming  from right here, which is the variable we give   to the object instance of fast API. And then  we just put through iPhones, save reload.   This is the basic command line just to run our  fast API project for our server. Once we eat,   enter, that you can see it says you've gone  running a PC application startup complete.   And it gives us this particular URL. That is  the URL that says where we should go to to see   our project. I'll just come into my browser  here, paste our URL, hit Enter. And boom,   you can see that I have named first data,  which is exactly what we returned right here   as a response new first data. So this is how  you can basically just have a very simple API.   Now, pass API as is very cool thing that I like  most of everybody that works with fastpay. Like,   we just got the documentation  to automatically generate these   good looking UI documentation for your API.  If we go to slash Doc's. And we hit enter,   CCS fast API swagger UI. This is just like a  basic documentation for all the API's you have   on these your like website, or like your API  application, whatever you want to call it.   But as you can see, it says default, we have from  the endpoint of UI, just slash. And the function   is index, which is right here, function,  give it to the index. And as you can see,   using a get method, that's what it shows you it is  it gets metal, they just basically generate these,   like API for, like this documentation for our API.  And we can test our API directly from this place.   But we don't need to use postman or any external  service to test API, you can just come here,   click on try it out. I will say it execute. And  I come down here, he just give me the response,   which is named first data of whatever is being  done here. Now, we're also gonna go complex,   more in the video and show you how to like  manipulate all this data very well. But for now,   this is just the response that is being given back  to this page. And of course, if we go to the Oh,   students same response, so To this point  we've talked about, first of all, we created   our first API, we made sure we installed all our  past API, you recall on everything we needed.   I explained, endpoint, what endpoints are  and get post, put, delete, implemented.   And yet again, we created our first API, and also  showed you how to use documentation of fast API.   So that's basically all about  reaching our run our first API.   Now, let's talk about our endpoint parameter.  Name parameter is basically used to return a data   relating to an input in the part or in the  endpoint, basically. So we can do that using   either a part or a query. So we have two  input parameters, which are path parameter   and a query parameter. I'm going to show you I  illustrate these right now. But first of all,   let's have low year as a new dictionary, our name  is students. It just filled out correctly, the day   dense. And there's a key with an ID of one, unless  you have that as another dictionary, lesson name.   Give you like john. These are the  age this C 17. There's a class   yet. So this is just a basic, make that small  caps. This is just a basic Python dictionary,   we just have one field India, this is a key, and  this is the value. So what we want to do now is   that we want to return the data of this particular  student using the student's ID. So in the   field, by key, let's say slash, we  can have a parameter like slash,   it's then slash one. So while you  have one It means is you return   the data with the student the as the ideal  for. So before I get into these, let me   explain what I mean by a pass parameter.  More. So let me just come down here.   Let's say I have a website like google.com,  slash, and they have get student   then this is just the basic URL to get a student.  And it can just basically show me all the data we   have in this dictionary. But let's see how to get  only a specific study like this to date, which has   the ID of one, and I can add another endpoint. But  now this endpoint will be dynamic is going to be   like a parameter that the user inputs, that will  be something like slash, then can be one, then   when we go to this URL is the user that has the  idea of Wanda is going to be returned to his to   his user as the idea of two. So let's cancel this  and just go straight into it. So we have this   object right here. And then what want to do right  here in app dot get place first of all, have a new   endpoint, app dot get also why isn't using I  get, and this time around, let's say get student.   Now we have this endpoint name gets  to them. And we'll put slash again,   I now want to take a parameter dummies  want to take an ID of what a user should   input. The first To do this, we'll use the  curly braces, and they will say student   underscore ID. This is just telling us the  previous ID huge basically be collected. And now   they Jeff, this creates in the normal function  of Cassie gay student. Now, remember right here,   it was just blank in euros not in India,  but now we're collecting students ID   underscore ID. And this should be equivalent  to whatever you put right in here.   That does what he just being collected. And  we have to specify the data type of this,   which is our integer so the ID should be our  integer now, or we can just do is to return   students. We're returning students,  which is from year is in the student ID.   So let me explain this. One more Time, what this  is doing now is that we have these adult guests   slash guest today, slash why now why isn't it  curly braces, that's fine like a variable mpg like   variable a dynamic variable. So whatever these  are input here is what is going to be used to get   the student. So d f, get student  there now, initializing the student ID   thing we're giving is like a data type of int,  that means it must not be a string or a boolean   value, it has to be an integer. And then we  just say return students who are turning the   student with the students ID. But what I mean by  this, you know, in a normal Python dictionary,   if we just want to return these students,  because it has a key of one because the students   want. And this is basically just going to return  the value of this one. But since one is to be   dynamic, I want you to do what the user inputs, we  change this one to the students ID damage whatever   the user inputs, the key of that is what should  be, and not, let's say user input like five,   and we know of that here, just gonna give you  like the channel found or something like that. So   let's save this. First of all, let's just  go test it out. If we come back here,   and let's refresh this page. Now you can  see that we have a large guest student.   And instead he knows the names are Roscoe ID  that we call me utilizes students ID is required.   That means we can just test this out, I say  execute the we try to try this and execute   T, it says that we need to input something  here. Now we put one, I say execute.   We see now that gives us a response of named john  17. On year two, that is basically this one right   here. So if we come here now, and then we  try to put something that is not the like   three, I'll say execute. You see the ISIS internal  survey Rodas because there is no detail like the,   of course, let's just go to the URL direct  directory directly, we say get student   finish student then slash one. You see now that  we have john age, we just have basically dat data   proceed to internal server error. Let's go back  to the docs, the does what's the path parameter   is basically all about what we can make it more  we can add more details to it. Or we can say let's   say we can make it compulsory. So let me come back  here. Let's say we want to add more details to   this student id like, you know, when we are  serving this API to a user, the user manual really   good like you really name this today's idea, we  just say student ism, I know understand what this   is like, do we need to pass the student name, or  the student's age or the class or the ID. So if   we don't have a surface financial name, we can  use like, something we need to import. And then   that is going to allow us to have a description of  it that the user can know what to input. But first   of all, let's come up here and input path. To  say that we don't need to have an dialogue,   we can just press comma inputs path, because  it's from past API inputs in it. So now that   we have parts imported, we can just say student  ID, below int equals two, then we can say path.   First of all, we'll say none. Now this non is  so there, if the student, if the person doesn't   input anything is just going to leave it blank  or is not going to once Iran is just gonna like   bring out an empty data. So just to like catch  the error. Remember, when we did it back year,   when we tried to get without inputting  something, he just told us that we need   to input something. That's just what this  is doing. And now we can add a description.   Now in this description, we can do something like  we want the ID of the student. You want to view   like that. So now this is just the description  we are giving it. And once we have this,   if we save it on then recall to our code right  here. And let's just try to refresh the page to   refresh dogs. And then we say get student.   No, because he writes in distribution. He says  the idea of this today you want to say just more,   giving us more description or more details of  what we really want to collect. What you also   more attributes is not just only does it come back  to our code, we have more attributes in this path,   we have attributes like less than two, let me just  quickly come down here again and experience it.   But we have let greater than gt GT, this just  means greater than, is self explanatory, we have   less than, we have D, which is greater  than or equals to also have LD,   which is less than or equal to. So this is just  telling us since we are collecting an integer,   we can specify whether the integer want to collect  must not be greater than 50, or must not be less   than one or zero or something like that. Let's say  we don't want our integer to be greater than zero.   But we want it to be greater than zero, so it  must be greater than zero. Let's save now, we come   back here, it refresh. Now, let's try it out right  here. Let's say we try to use zero and say execute   the gives us this error say, ensure the value is  greater than zero. But that's because we specified   in yellow, we don't want it to be less than zero,  it must be greater than zero. And we can also add   to, let's say we want you to be greater than  zero, but less than, less than, like three.   That means the number should be from one to  two. So if we go against any of these rules,   for me again, in the refresh button, and  right here, we tried out the let's say we   do three presses acute trauma give us an error,  we say ensure the value is less than three,   when I we do two is gonna give us internal server  error does because that data is not found there is   no data with the key of two with do one, you know,  we have that data right here. Right here, we just   go here, the key of one to come back here. Now  you see that gives us a data that does our we can   just add more values. Or we can Yeah, we can add  more values and details to this particular API.   Now let's talk about query parameters. The  query is used to pass a value into a URL   that is quite similar to the path parameter. Let  me quickly explain that again. Now in a URL, like   I say, google.com, slash, and we have results. Now  when we have these question mark, and then we have   variable name equals to something like Python.  Now in this URL, the query parameter is this   search equals to Python. So this is just basically  giving us an like a key and a value. So this is   the name of the variable as we pass undefined is  very, very, very similar to the path parameter,   right here. And the path parameter, you know, we  have a name of student ID, or we have a value of   whatever the user inputs, that's just our  which is zero. So we can have like a URL,   and then instead of having slash or something to,  you know, be on that same endpoint, for right now,   is gonna just have a query attached to that  end point. to having this said, let's just go   straight into using these practically, what  I want to do now is I want to create a new   person a new endpoint, I'll say app dot  get also. And then let's say slash get,   I think by the want to get the student data  by the name, this right here, we're getting by   the students ID for the difference between the  query parameter and the path parameter is that   in the patch parameter, we need to add whatever  the parameter wants to collect in the URL in the   endpoint right here. When it query parameter,  we don't need to do that. Or we just need to   do so coming to our function. This fire function,  I say get student. And then we'll just say, name   is a string. So right here is very similar.  You see it in the path with the student ID is   equals to an integer. But we already defined our  students ID in the URL. But here we didn't define   any team but we are now coming into the function  and defining it. So once you see something like   is it ready, takes it as a query parameter. And  then once we have that I'm just going to these our   particular function. And now, once a user  comes to this URL and do something like this,   I'll say name equals to like john, we want to  get the data there as the name of john, to this   as duties now, and I use a for loop  and say for a student, ID, student.   If students were brackets, student ID, name.   posts are the name which was passed.  And what we just want to do is return   to dance. That particular students  ID, none of this is just return. Data.   Thought. What this is doing is, first of  all, is looping through the values we have   in this student wise in the key of students  ID. In this student, we say if the students   have this student ID, the name of it is  because with name which has been passed,   let me explain his will to we are looping through  this student's ID using while looping through this   students dictionary using the students ID. And  this Jeanette ID is this. So we can name this   anything right here, we can just say ID anything  we don't want to name. But if I say ID pattern   automatically see that as a keyword. So I'm just  going to put a student's ID so it's original.   So now we are looping through it using these,  I will say if the student with this student ID,   the name of it is equals to  the name which is being passed,   they want to return that particular student. If  not, you just say data not found. Now to make   a query parameter, let's just go and test  it out. Let's come back here. Now issue.   Good. So now we have guests by name, or we see  yet we are name required. We can just you know,   we say john, once we execute that should work. So  as you can see now is named john, because it gets   that is really a value by data with the new module  where we try something like let's say, a team.   We execute, gonna say data loss, because  we don't have any data rights in year   with the name of team. So that's basically how to  just create a very simple query parameter and fast   API. Now to make these our query parameter option  now, we can do the so is very simple. Let's say   we just want to make it optional. Like we don't  want to require we come here, you see that it   says it is required right here. Let's make this  option now. We can just say name, right here in   this string Kathy equals to not equals to no  is no more required, we can go year. So dogs   always say get by name, Katsina, it doesn't say  da required again. That means we can try that's   gonna give us an error or something. They just  says data not found. But now is no more require.   Now does one way to do it. But the best practice  is to use the default option now method that   past API is for us. For us to use  these, what we just need to do.   First of all, we'll come right here  is very easy, we just say optional.   And then equals known. So this is just going  to make it optional for us. But before we   can use this, we need to make sure we put  that option now, they from typing import   option. That is just to make it the best  practice. Because these are facts epi   recommends that if we need documentation, also  do it the normal way or just the other way,   not the normal way. This is the normal way.  So we can also do it that way to keep things   simple. We just want to you have a clean  code and a more readable code as the main   points to make it more readable. We can also  use this so right No, this is gonna be like,   not required is going to be optional. So now,  let's say we want to add another query parameter   into eloquent to have to query parameters. How do  we do this? I'm going to show you something. Yeah,   let's just have a comma, I will say test  it. So we just have a query parameter   of JSON is an integer. So if I try to run  this, we should get an error. And I'm going   to show you why we have that error right?  Now. Let me call me not here, a browser.   So okay, you can see that it's  not even going if I come here.   Now you see dices syntax  error, non default argument,   follows default argument. So what this is just  saying is, we have, as you can see, right here,   we have named optional. And then we have test,  which is optional. So Python doesn't allow us to   have like, an optional argument before, a required  argument. So fast the back covers is about Python   doesn't just allow us because Python is a language  writing. So we also have to stick with Python.   If we come down year, one thing we can do is to  just switch to places like changes, or bring it   here or something, we can also do that. But the  best way to do this, so we can have a limited   query parameters and have them anywhere we want.  It's very easy, what we can use to say asterik sa,   coma. So once we have these, we can now write  it if we have a default parameter or optional,   or whatever required is going to  work since we have this now. Gonna   be able to take care of anything that comes  after it. Never call me on it, refresh. It   that should work. Well. Let's see, let's have  that a reloading? Yeah, there we come, you know,   she's ready reloading. And that should  work. Now. Let's give it one more trial.   Okay, that's taking a while to reload we  shouldn't. But that's just basically how to   solve that particular error, or when you're having   an optional parameter before a required query  parameter. So I hope you understand that concept.   Now let's talk about combining  path and query parameters together.   Now, sometimes you might want to do this,  well, most of the time, you might not.   Let's say you want to get two different values  from a user, like let's say his ID on his name, or   the class or whatever, you might want to combine  a query parameter alongside with a path parameter.   First to do these, you know, right here, we  already have weary parameter of name and test,   the length of the path parameter, let's  also call it the student ID, the slash K,   students underscore ID. And then  since we are defining initializers,   to net ID in the path, and we  also come here, and then say,   dent underscore ID, and then we give it  int, j comma. So since we have eta on here,   that is a path parameter, which only in the  function that is a query parameter. So that's   just the basic difference you just need to take  note of. So we are between these two places does   that. So now we can just easily test this out?  Actually, we even when we collect the students,   Id one organizer for anything? Yeah, because  everything was doing is basically getting it   by the name. But that's just how you can combine  a query parameter with us come back here. Now.   We hit enter. So if we say get, no, this is  not what we need. We want to get by name.   We say get no, you see that we are name  test. We should also have students ID   to strike out as the key. If we come back here.  Did I okay, we didn't save our file. Let's make   sure we save our file back ducks it and now  we have student ID which is also required.   That just the basic concept of like combining  parameter on a query parameter together.   This part we're going to talk about request  body and the POST method. So the request   What it is, is like the information or  data pass when creating a new object   using the POST method. Now to do this, first  of all, let's import something right here   for the base. So say from by downtick import  base model, just to be more elaborate. The   request body is like the data pass when you  want to create a new object or a new data of   t. So, I'm going to explain this later, like,  you're gonna see what we're talking about, you   don't need to like know the definition or whatever  that is, just to know how to use it in a practical   case. So now that we have this base, Moodle  importer, we're going to create a new class.   And this class, we just want  it to be similar to the student   dictionary, and let's name the class  student going to take from the base Moodle   let's have a name should be a string is  of an age and use that as an integer.   And then they have a class. Now I  would have loved to have a class boy,   Cassie is seen it as a key word. So let's change  out to like year, the year of the student and   that should be string also, they just call  me Mr. of class here. So we can use it,   you know that we have these, what we  can just do want to create a new path   now. But this time around,  we're gonna use a POST method.   First to do this just similar to say arts app dot  post proposed. And now we will say create students   now wants to create a new object of students are  going to take a path parameter, or students ID,   I know what we do, when we take a path parameter,  we have to define that in the function. So create,   underscore, the desk. router, define our student  underscore ID as an integer. And what the next you   want to specify is student. The students know  what it is, is basically the details that the   that the user submits. So in order to create a new  students object, for using this particular class,   to know the details, let's say the details, the  name that the user saw me the age and the year   is what is going to be saved in this student.  So want it to be because to this student   Moodle, you can see that  these with a small letter and   capital letter. So that's what's really  different. So this like key value,   but now that we have that just go straight to say,  if the students ID that was passed. In students,   what we just want to do was  say, return like an error,   say student exists.   So this means that if the student ID in  is already in students, and the student   ID right here, then what we just do is to say  return an error, does history already exist,   damage the concrete, the same student  with a student with the same ID twice.   What he does not the case, Justice students.  Within the student ID equals to student   I tell you that the student is whatever the user  broad or submitted using this post metal, but now   that we have these, we've created a new object of  a student. And then we can just basically return   students of that student ID. This  is just the code we need for this.   So before we test this code, or let me  explain what we did in this code, again,   what we're doing in the score above register, we  are taking a path parameter of an ID. So this is   per parameter alongside with all the details  of the student, and they were using that to   create a new student object. So please just go  ahead and test this code to save the Permian.   ducks. Now you can see that we have posts not  get any more great students, our students ID   is required. And they can see it says request  body also required. That's what I talked about.   Talked about the request body is basically the  details as the name PhD year it needs orders,   let's try it out. One of our students  have to, though, we'll say, just say, Tim,   give Tim age of 12. See  nine. Now, if I execute this,   see now that it just gave me the response of  what I just created. But now we have a student   ID of two, if I call to get by student's ID,  so let's just get the students using the ID,   we should love that now safe. So let's say to say  execute. Now we can see that we have this team,   with dummies, it has been saved right here. But  one thing about this is that it's saving it in   like a memory. So if we refresh this page,  that is gone. But you know, we are working   with real world applications, you want to save  like your database or something like that. So   you can see that we created a new object of that  now. And then we just use the get to get that URL,   if we want to read what already exists like  true, and want to create it again, let's execute,   we say says error students already exist, we can  create with the same ID twice, does what's good   about that? Let's go back to our code. So this is  basically how we can just use the POST method and   the request body to create a new object in your  new object in our data in our database, basically.   Let's talk about the ports method. As I explained  earlier, in this tutorial, the put method is used   to update something that already exists. So  to do these, first of all, let's have a new   endpoint policy up those goods. This time around,  we'll say patch update. affairs today student   and they want to collect the ID of the student.  So we know the student in which we are updating.   Now let's have a function saying date. Student   we also have to defend us  today and ID as an integer.   Now students just similar to what  we did here, we know our collecting.   Vantage goes to this student. Well,  now, I want to explain something. So   right here you can see that it says to that is  because of studio. But when we are posting these   posting a particular data to this URL, I  will say this student is equals to student,   everything has to be essentially all the field in  the composer. So you've become here now. And we   give a name field and we don't give an age field  not going to work if we are using the students   module for the update. So we need to create  a new model, but this time around to make all   of these optional. So the reason for these is so  that because when a user want to update a value,   you only want to update the name and not age  only wants to update the year and not the name of   a new our body we are using this student  class to for the update method. Also.   The scenario as the user as to input all the whole  data now means he has to change audio data every   time he wants to update something which is not  a good practice. Let's just quiet and create.   Plus our name is update. Student   and does also take from the base model.  Same thing name. Now we'll say optional.   Trained person just to make it optional. To do the  same thing for the age. Optional, trained integer   person and then exactly Simply for  the class right here we are using year   optional and this is a string equals no  now we can use this of this students model   as a reference here. So, these notes tonight  again these objects today now with these each   of it is optional see we use I gives only one  value the other values can still remain the same   does very good. And now, what we just want  to do to say if student ID not in student   will say return an error of like these   particular student does not exist or something  the world this is okay let me quickly write that   though that under students does not exist,  what this is doing is first of all it checks   if the student ID is not a student the damage if  the the ID which was being passed to what we're   doing is if we want to update this today we're  going to pass the ID of the student then whatever   we want to update. So, it will first check if  the ID is present in students will not present   it to you the student does not exist today. You  also update does not exist at least you have to   have a student before we can update that data.  We have to check that first. But if it exists,   we can just do something like students   didn't ID equals to student and then  right now we can just return student   This is exactly the same thing we did right here  dance ID exactly what I'm going to show you where   the arrow is in this particular is not an arrow  but where the touch is if we come near now on test   days see the refresh button now you can see is  the put we have the put method and no let's first   of all let's create a new student so straight  out this are creating with to let's say Team   12 nine now we execute this we have a new  objects or new data or the counterpart want   to update this student. So let's try it out. And  what's up JD students with the ID of two witches   team when I want to change the name to Tom not  team we don't need the age or the dummies this   option also we don't want that he doesn't know  what to do. If we execute this now you will see   what will happen. So now it says named Tom age no  yeah no because we didn't specify these he says   no. They were all the way to get your student  by ID and I just want to get this student   into an execute what is going to happen now you  can see he doesn't even show us the age again.   He doesn't show that he's 12 years old. The is  in year nine. So it has been overwritten so it   because we didn't provide this age on year when we  are updating it also via ride rides as no damage   has no value. And this arrow is coming because we  just did students with us today Id is equals to   student needs to know is whatever the user passes.  So since we didn't pass anything, it just updated   our student that already has a value of this it  has nothing which is but the first take care of   these we are going to have to do it in like a  manual way to come up here to say if a student   Let's name is not posting non   numbers if there is something in what the user  past then doesn't want to update on say to   dance. Dance ID does the name will be  updated to the student. This one does name   is exactly the kind of code wants to  use I'm also going to do the same thing   for the age and the class or the year, the  eve student that age is not equals to none.   See, the dance with a student ID, the  particular student does age equals to   the dent. But ah, Now, last time, we're gonna  have to do it for the year, that's here,   now equals to none, I mean, you're giving us an  empty value, then that's the only time when we now   want to update sort of data particular value, but  a particular key, so you don't give us something,   we are not going to update it. When we give  us something, we're going to update it,   then to a year. This is just the code to take  care of that error. So now we save this. Now,   this is very good, because we've  taken care of that particular error.   And now let's just go ahead and come back  into your and then we eat fresh, this.   Great, but what wants to do first of all,  let's create a new dent to him. Both yes or no.   Let's execute. And now we have that, let's  come to our outputs and update that team.   For now we want him to be 15 years old to Let's  leave this name as blank. Well, now the age wanted   to be 15. So you can see that now we didn't pass  the name or the year. But if it executes, only   so let's see where the error is coming from this  expecting proper name equals interval codes. Okay,   so it wants this to be in double cordial because  it's JSON data. Let's do this or execute.   Okay, especially improperly named interval  codes. Okay, this gives us an error   enclosed in double quotes. Let's see. Now  let me tell you where the arrow is from if   you don't have anything after it, like you  do have another value right here something,   just remove this comma, we don't need this  actually, we should not need that because an   integer to make sure you don't have a comma at  the end if there's not enough to read. So now   let's hit execute. And if we come here now you see  there are only 15 was updated and alighted at 15.   But only 15 was updated. Now we have team  a nice to intact. So this is what we want,   we can also do it again. And now we can just  update our name. And we wanted our name.   Now be Tom. The execute procedure, we now have  Tom age of 15. year over year nine, this is   exactly what we want. If we come back, you know  and try to get to didn't try it out. Let's try to   do it, you can see that we have  the named song working perfectly   the age on the year. So this is exactly what we  want to get. This is our main go. I'll also come   down here to get by name. Let's test that out.  So let's try it out. We have to we have the   name of Tom. And as I said this can be anything  because we're not using it. If we execute this now   it gives us an internal server error does  because of course that doesn't. It doesn't.   Now there are so let's see slash to the name of  song on test 32. So the reason why is because   we definitely changed some values right here  are some code right here in where we're start   to get to take care of the liter. But now that's  basically how we can just update some data in our   in our database if we are using a real  data. It's not like a memory or like   I will say a cookie because the cookies in the  browser or is it like a memory once we refresh   or like a session once we refresh that is gone.  But now, this is how we can just simply do this on   I hope you understood why we went about doing  these. So if you read this code will you see   our saying if this, whatever the value is  is not known, that means it is not empty,   then that means there's something  there that doesn't want to update it.   So I hope you understood what exactly what  we did in this bar. And this next part,   we are going to look into the Delete method. The  delete method is self explanatory, just delete   a data object from our database. What we  can just do know is to add a new endpoint,   we can say add up dot delete, and then   slash delete shouldn't blush let's take  the idea of the student want to delete   as a path parameter, and then define  our function. Elite student new student   this guy ID wants you to be an  integer as well we're collecting   and now we'll check if the  student ID is not in student.   So if he's not a student, that means  it doesn't exist and we just return   an error that what you're trying to  delete is not even in our database,   it needs to be in the database for  you to be able to delete it to arrow   judgment does not exist then you have to create  us to know first before you can try to delete   but it does not decay, go ahead  with our code and delete that   that's two different questionnaires ID from the  students and they just return back a message   thing that didn't deleted successfully now  this is a basic way to just be able to delete   data or value from a database first come here  and test this out. Now if we play around with the   pose first of all we have to create a new  object before we can do that. So let's see do   this a for Jerry 20 years let's  see year 13 Now let's execute this   case study exit so as you can see I press that  twice so that's why I say students exists but I   come here to my get without really created it when  I press it the first time when I mistakenly press   it again so let's say to execute we can see we  have Jerry 20 years return. If I come down now to   delete you can see we have this delete function.  Now that we have this delete function is is   right out now by just typing to an eating execute  j student deleted successfully. Now we might   not know if they are related it let's just go  ahead and press check to see if we execute now.   He says internal server error does  because the student doesn't exist   again. So you also come in now and try to execute  again. He says student does no it is I'm a student   I'm trying to delete does not exist. So  this is how we can use the Delete method.   The Fast API geysers gonna be all for this video.  Thank you so much for watching to this point. In   this video we talked about fast API's and all the  basics and fundamentals you need to start working   with fast API. Thank you once again for watching  this video and I'll see you in the next one.