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Consume APIs using Python and requests

brayvasq profile image Brayan Vasquez ・4 min read

Hi Everyone!. In this post, I want to share with you a little guide that will show you how to consume an APIs using Python and requests.

We will use the following API, https://jsonplaceholder.typicode.com/. That is a simple API for posts.

Requirements

  • Python (I use Python 3.8.2)
  • Pip (I use Pip 20.1.1)

Setup Project

To create our project we are going to use virtualenv, to create an isolated python environment for this project. However, you can also use pyenv or venv.

So, first, we have to install virtualenv.

pip3 install virtualenv

Now, we have to create the project folder and set up the virtualenv.

# Creating a project folder
mkdir apis-example
cd apis-example

# Creating the virtual environment
virtualenv env

# Activate the virtual environment
source env/bin/activate

# Create our main file
touch main.py

NOTE: To exit the environment you just have to write deactivate.

Install dependencies

To make HTTP requests we will use the requests module. We can install this module using the following command.

pip install requests

We can see the installed dependencies with the following command.

# Installed dependencies
pip freeze

# The above mentioned command will list something like the following
certifi==2020.6.20
chardet==3.0.4
idna==2.10
requests==2.24.0
urllib3==1.25.10

We can also export our dependencies.

pip freeze > requirements.txt

And install our dependencies from a requirements.txt file.

pip install -r requirements.txt

List posts

Now that we have the necessary modules installed, we can start writing code. First, we must import the requests module, which will help us to consume the API.

# main.py
# import section ....
import requests            # import python module
import json
# ....

Now, we will define the base url.

# main.py

# Constants section ....
# API base URL
BASE_URL = "https://jsonplaceholder.typicode.com"

Ok, we will create a function called get_all that will show all posts.

# main.py

# Methods section ....
def get_all():
    """
    Make a GET request to the API rest to get all the items
    """
    url = BASE_URL + "/posts"
    response = requests.get(url)

    json_result = response.json()
    print(json_result)

Our main function will be the following.

# main.py
# import section ....
import sys

# Main section ...
if __name__ == "__main__":
    if len(sys.argv)> 1 :
        if sys.argv[1] == '--help':
            print('Info: ')
            print('--help List the options to send an email')
            print('--list Show all posts')
            print('--show Show a specific post')
            print('--create Create a post')
            print('--update Update a post')
            print('--delete Delete a post')
        elif sys.argv[1] == '--list':
            print("Listing all posts")
            get_all()
    else:
        print("Please give the type of message to send.")
        print("For help execute `python main.py --help`")

We can test our function by executing the following command in our terminal.

python main.py --list

# Listing all posts
# [{'userId': x, 'id': x, 'title': 'xxxxxxx', 'body': 'xxxxxxxxxx'}, ....]

Create post

Here, we will create a post using a POST request. First, we will create a method called create_post.

# main.py

# Methods section ....
def create_post():
    """
    Make a post request to the API rest to create an item
    """
    url = BASE_URL + "/posts"

    # Request headers
    headers = { "Content-type": "application/json; charset=UTF-8" }

    # Request body
    body = {
      "title": 'foo',
      "body": 'bar',
      "userId": 1
    }

    data = json.dumps(body) # parse a dictionary to json string format

    response = requests.post(url, headers=headers, data=data)

    json_result = response.json()

    print(json_result)

Add the option to our main function.

# main.py

# Main section ...
if __name__ == "__main__":
    # ....

    if len(sys.argv)> 1 :
        # if ....
        elif sys.argv[1] == '--create':
            print("Create a post")
            create_post()
    else:
        # ....

We can test our function by executing the following command in our terminal.

python main.py --create

# Create a post
# {'title': 'foo', 'body': 'bar', 'userId': x, 'id': x}

Show a post

Here, we will show a specific post using a GET request. We will create a method called show_post.

# main.py

# Methods section ....
def show_post(id=1):
    url = BASE_URL + "/posts/" + str(id)
    response = requests.get(url)

    json_result = response.json()
    print(json_result)

Add the option to our main function.

# main.py

# Main section ...
if __name__ == "__main__":
    # ....

    if len(sys.argv)> 1 :
        # if ....
        elif sys.argv[1] == '--show':
            print("Show a post")
            show_post(1)
    else:
        # ....

We can test our function by executing the following command in our terminal.

python main.py --show

# Show a post
# {'userId': x, 'id': x, 'title': 'xxxxxxxxx', 'body': 'xxxxxxxxxx'}

Update a post

Here, we will update a post using a PUT request. We will create a method called update_post.

# main.py

# Methods section ....
def update_post(id = 1):
    """
    Make a post request to the API rest to create an item
    """
    url = BASE_URL + "/posts/" + str(id)

    # Request headers
    headers = { "Content-type": "application/json; charset=UTF-8" }

    # Request body
    body = {
      "title": 'fooz',
      "body": 'barz',
      "userId": 1,
      "id": id
    }

    data = json.dumps(body) # parse a dictionary to json string format

    response = requests.put(url, headers=headers, data=data)

    json_result = response.json()

    print(json_result)

Add the option to our main function.

# main.py

# Main section ...
if __name__ == "__main__":
    # ....

    if len(sys.argv)> 1 :
        # if ....
        elif sys.argv[1] == '--update':
            print("Update a post")
            show_post(1)
    else:
        # ....

We can test our function by executing the following command in our terminal.

python main.py --update

# Update a post
# {'userId': x, 'id': x, 'title': 'xxxxxxxx', 'body': 'xxxxxxxx'}

Delete a post

Here, we will update a post using a DELETE request. We will create a method called delete_post.

# main.py

# Methods section ....
def delete_post(id = 1):
    url = BASE_URL + "/posts/" + str(id)
    response = requests.delete(url)

    json_result = response.json()
    print(json_result)

Add the option to our main function.

# main.py

# Main section ...
if __name__ == "__main__":
    # ....

    if len(sys.argv)> 1 :
        # if ....
        elif sys.argv[1] == '--delete':
            print("Delete a post")
            show_post(1)
    else:
        # ....

We can test our function by executing the following command in our terminal.

python main.py --delete

# Delete a post
# {'userId': x, 'id': x, 'title': 'xxxxxxxxxxx', 'body': 'xxxxxxxxxxx'}

Final Words

Thanks for reading this post and you can find the code of this guide here.

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