python Creating a RESTful API using Flask?

REST API stands for Restful API, which allows the integration of applications or interaction with RESTful web services. It is now growing as the most common method for connecting components in a microservice architecture. APIs will enable you to get or send data to a website and perform some actions like crud operations to get your task done over a web service. Each website uses different types of API, like stock market trading websites integrating with Sensex or Nifty to get a current price and ups-down. Ticket booking apps use a desired single portal API to keep updated data at a familiar interface.

restful api python flask

If this command achieves the desired result, you must replace all commands in the rest of the article. Many apps you build have everything happening on the same server, and they don’t need CORS. However, in the case of an API or an application that requires an outside request to have POST access to your server, we need to add CORS. The default behavior is to block requests so that we don’t have malicious scripts being run on our server.

Setting up Flask

The post method obtains request data in JSON format and adds the data to the database. Here we create a ProductView class that defines a get and post function. The get function retrieves the products from the database and paginates the results.

  • Unfortunately web browsers have the nasty habit of showing an ugly login dialog box when a request comes back with a 401 error code.
  • To get the two to talk to each other, I built a Flask API which would allow my partner to send JSON requests, and receive a JSON formatted responses from my model.
  • The difference is that it transforms the given amount to be negative.
  • Now that you’ve got requests installed, you can start sending HTTP requests.
  • However, when we are using Flask to develop, there is one primitive thing that we need to look out for.

In the recent software world, REST APIs play a major role as a communication channel between different services. It has become the de facto standard of passing information across multiple systems in the JSON format. This is because it has a uniform interface to share messages across two different systems.


The next step is creating the application instance using Connexion rather than Flask. Internally, the Flask app is still created, but it now has additional functionality added to it. Connexion will use “people.read_all” to find a Python function named read_all() in a people module of your project. You’ll create the corresponding Python code later in this tutorial.

restful api python flask

Like other prominent programming languages, Python contains modules, which allow programmers to organize source code by subjects or functionalities. Modules in Python are files grouped in folders that can be imported by other Python scripts, similar to Java packages and C# namespaces. You only need to create a folder restful api python flask and add an empty file called to it to build a module in a Python program. You’ll create a file called and add five lines of code to it after installing the program. You don’t need to nest this file in a new directory because you’ll only use it to check if Flask API was installed correctly.

The project structure

This class is descended from the Schema superclass, which is specified in a package that has yet to be installed. In a simple use case like the one above, using dictionaries is sufficient. The initial endpoint of the application will be defined in this script. Pipenv is a dependency manager that allows packages to be installed per project while isolating projects in private environments. If you’ve used NPM or Ruby’s bundler, you’ll recognize the essence of this utility.

restful api python flask

In the example above, I have written the get() and post() methods corresponding to HTTP’s GET and POST respectively. The easiest way to secure our web service is to require clients to provide a username and a password. The clients of our web service will be asking the service to add, remove and modify tasks, so clearly we need to have a way to store tasks.

Defining a Docker recipe (Dockerfile) will help us run the API in different environments. That is, in the future, we will also install Docker and run our program on environments like production and staging. Inside the main module, let’s create a script called In this script, we will define the first endpoint of our application.

  • When you access /countries, Flask calls the decorated function to handle the HTTP request and return a response.
  • You’ll notice that the FastAPI application looks similar to the Flask application.
  • This part of the documentation will show you how to get started in using
    Flask-RESTful with Flask.

In this tutorial, you’ll make Cashman, a tiny RESTful API that lets users monitor their income and expenses. As a result, you’ll establish the cashman-flask-project directory. After that, you’ll launch the project and manage our dependencies with pipenv. In today’s interconnected world, building robust and scalable APIs is essential for seamless integration between different applications.