An API is an intermediate software agent that allows dependent applications to communicate with each other. APIs provide a set of protocols, routines, and developer tools enabling software developers to extract and share information and let applications interact in an accessible manner.
Be it web APIs that connect web applications to other platforms or APIs used by IoT devices to collect and process data, the use of APIs has expanded like never before.
REST (Representational State Transfer) is one of the most lucrative categories of web-based APIs. Based on Uniform Resource Identifiers (URIs) and HTTP protocol, REST-based APIs use JSON for data formatting which is considered to be browser-compatible.
SOAP-based APIs (Simple Object Access Protocol) use a type of protocol known as Simple Object Access Protocol, which is a common communication protocol. This helps them in providing higher levels of security and makes them better at accuracy as compared with the REST-based APIs.
one of the most advanced sets of web-based APIs where open-source data query and manipulation language is used. This makes it easier for forming a definitive pathway for the runtime that plays a vital role in fulfilling queries with the pre-existing data.
XML-RPC (Extensible Markup Language-Remote Procedure Call) Differentiates itself in terms of information security and the use of XML format that is specifically designed for transferring data. When compared to SOAP-based APIs, the XML-RPC protocols are easier and much simpler to use since they use minimum bandwidth.
A two-way interactive communication session between the user’s browser and a server can be made smoother and faster with the help of an organized set of APIs known as WebSockets. The entire process involving this doesn’t even require having to poll the server in order to receive a reply.
APIs interconnect individual systems that contain data about people, businesses and things, enable transactions, and create new products/services and business models. The popularity of APIs has grown significantly in the last decade or so.
The most common term for creating simulated components is mocking, but others are also used, and partly apply to different things; stubbing, simulation, and virtualization. The basic concept is the same - instead of using an actual software component (an API in our case) – a “replacement” version of that API is created and used instead.
- Stubbing: mostly a placeholder without real functionality
- Mocking: basic functionality required for a specific testing or development purpose
- Simulation: complete functionality for testing or development purposes
- Virtualization: imulation that is deployed into an operational, manageable and controllable environment
API mocking has a number of extremely useful applications. To demonstrate this, we will use an example with a component that uses a number of APIs to talk to a number of auxiliary systems and services (Legacy, Mobile Apps, Infrastructure, Databases, Peer Services, 3rd Party Components):
Create, Read, Update, Delete—are crucial functionalities of API endpoints that need rigorous testing to ensure robust and secure interaction with a web application's back-end.
Here's a concise guide on testing CRUD operations for APIs.
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Firstly, set up your testing environment with the necessary tools and frameworks like Postman or advanced automated testing suites if you're looking at scale.
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Create: This will involve sending a POST request to the API with a payload that includes new resource data. Ensure that the response status code reflects successful creation (often a 201 code) and verify that the resource has indeed been created with all the correct attributes.
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Read: Test the 'Read' functionality by sending a GET request. The API should return the requested resource or a collection of resources. Validate the correctness of the data returned and whether it meets the specification. Additionally, test for scenarios like non-existing resources or unauthorized access.
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Update: Next, the 'Update' operation can often be the most critical. Utilizing PUT or PATCH requests, make changes to existing data and validate the success of these operations by checking for appropriate status codes and performing a subsequent read operation.
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Delete: Finally, the 'Delete' operation is tested by sending a DELETE request to remove a resource. Confirm the deletion by ensuring that subsequent READ operations for that resource yield a 404 not found status code.
This is a basic example to get you started with creating APIs in Django using the Django REST Framework.
Django REST framework, a robust and versatile framework for creating efficient and scalable APIs. This guide is designed to provide you with a clear and structured approach to Django REST API, ensuring that both beginners and experienced developers can navigate and utilize this powerful tool with ease.
python -m venv myenv
myenv\Scripts\activate
pip install django
pip install djangorestframework
python -m django --version
Similarly, you can check the Django REST Framework version in your Python shell:
import rest_framework
print(rest_framework.__version__)
We'll create a simple API to manage items with CRUD operations (Create, Read, Update, Delete). Define the Item model: Edit myapp/models.py to define the Item model:
from django.db import models
class Item(models.Model):
name = models.CharField(max_length=100)
description = models.TextField(blank=True)
def __str__(self):
return self.name
Create and apply migrations:
python manage.py makemigrations
python manage.py migrate
Create a serializer for the Item model: Create myapp/serializers.py and define the ItemSerializer:
from rest_framework import serializers
from .models import Item
class ItemSerializer(serializers.ModelSerializer):
class Meta:
model = Item
fields = ['id', 'name', 'description']
Create views for the API: Create myapp/views.py and define the views using DRF's generic views:
from rest_framework import generics
from .models import Item
from .serializers import ItemSerializer
class ItemListCreate(generics.ListCreateAPIView):
queryset = Item.objects.all()
serializer_class = ItemSerializer
class ItemRetrieveUpdateDestroy(generics.RetrieveUpdateDestroyAPIView):
queryset = Item.objects.all()
serializer_class = ItemSerializer
Define URLs for the API: Create myapp/urls.py and set up the URL patterns:
Define URLs for the API:
Create myapp/urls.py and set up the URL patterns:
Include these URLs in the project’s main urls.py:
from django.contrib import admin
from django.urls import path, include
urlpatterns = [
path('admin/', admin.site.urls),
path('api/', include('myapp.urls')),
]
To add basic authentication, we'll use DRF's built-in authentication mechanisms.
Add authentication to settings: Edit myproject/settings.py to include authentication classes:
REST_FRAMEWORK = {
'DEFAULT_AUTHENTICATION_CLASSES': [
'rest_framework.authentication.BasicAuthentication',
'rest_framework.authentication.SessionAuthentication',
],
'DEFAULT_PERMISSION_CLASSES': [
'rest_framework.permissions.IsAuthenticated',
],
}
Create a superuser to test authentication:
python manage.py createsuperuser
Start the development server:
python manage.py runserver
You can now test the API using tools like curl, Postman, or your web browser.
Get list of items (GET request):
curl -u yourusername:yourpassword http://127.0.0.1:8000/api/items/
Create a new item (POST request):
curl -u yourusername:yourpassword -X POST http://127.0.0.1:8000/api/items/ -H "Content-Type: application/json" -d '{"name": "Test Item", "description": "This is a test item."}'
Retrieve an item (GET request):
curl -u yourusername:yourpassword http://127.0.0.1:8000/api/items/1/
Update an item (PUT request):
curl -u yourusername:yourpassword -X PUT http://127.0.0.1:8000/api/items/1/ -H "Content-Type: application/json" -d '{"name": "Updated Item", "description": "This is an updated test item."}'
Delete an item (DELETE request):
curl -u yourusername:yourpassword -X DELETE http://127.0.0.1:8000/api/items/1/