Build API clients for Python
In this tutorial, you build a sample app in Python that calls a REST API that doesn't require authentication.
Required tools
- Python 3.8+
- pip 20.0+
- asyncio or any other supported async environment, for example, AnyIO, Trio.
Create a project
Create a directory to contain the new project.
Project configuration
In case you're adding a Kiota client to an existing project, the following configuration is required:
- pyproject.toml > project > requires-python set to ">=3.8".
Add dependencies
Before you can compile and run the generated API client, you need to make sure the generated source files are part of a project with the required dependencies. Your project must have a reference to the abstraction package. Additionally, you must either use the Kiota default implementations or provide your own custom implementations of the following packages:
- HTTP (Kiota default HTTPX-based implementation)
- JSON serialization (Kiota default)
- Text serialization (Kiota default)
For this tutorial, use the default implementations.
Run the following commands to get the required dependencies:
pip install microsoft-kiota-abstractions
pip install microsoft-kiota-http
pip install microsoft-kiota-serialization-json
pip install microsoft-kiota-serialization-text
pip install microsoft-kiota-serialization-form
pip install microsoft-kiota-serialization-multipart
Tip
It is recommended to use a package manager/virtual environment to avoid installing packages system wide. Read more here.
Generate the API client
Kiota generates API clients from OpenAPI documents. Create a file named posts-api.yml and add the following.
openapi: '3.0.2'
info:
title: JSONPlaceholder
version: '1.0'
servers:
- url: https://jsonplaceholder.typicode.com/
components:
schemas:
post:
type: object
properties:
userId:
type: integer
id:
type: integer
title:
type: string
body:
type: string
parameters:
post-id:
name: post-id
in: path
description: 'key: id of post'
required: true
style: simple
schema:
type: integer
paths:
/posts:
get:
description: Get posts
parameters:
- name: userId
in: query
description: Filter results by user ID
required: false
style: form
schema:
type: integer
maxItems: 1
- name: title
in: query
description: Filter results by title
required: false
style: form
schema:
type: string
maxItems: 1
responses:
'200':
description: OK
content:
application/json:
schema:
type: array
items:
$ref: '#/components/schemas/post'
post:
description: 'Create post'
requestBody:
required: true
content:
application/json:
schema:
$ref: '#/components/schemas/post'
responses:
'201':
description: Created
content:
application/json:
schema:
$ref: '#/components/schemas/post'
/posts/{post-id}:
get:
description: 'Get post by ID'
parameters:
- $ref: '#/components/parameters/post-id'
responses:
'200':
description: OK
content:
application/json:
schema:
$ref: '#/components/schemas/post'
patch:
description: 'Update post'
requestBody:
required: true
content:
application/json:
schema:
$ref: '#/components/schemas/post'
parameters:
- $ref: '#/components/parameters/post-id'
responses:
'200':
description: OK
content:
application/json:
schema:
$ref: '#/components/schemas/post'
delete:
description: 'Delete post'
parameters:
- $ref: '#/components/parameters/post-id'
responses:
'200':
description: OK
This file is a minimal OpenAPI description that describes how to call the /posts
endpoint in the JSONPlaceholder REST API.
You can then use the Kiota command line tool to generate the API client classes.
kiota generate -l python -c PostsClient -n client -d ./posts-api.yml -o ./client
Tip
Add --exclude-backward-compatible
if you want to reduce the size of the generated client and are not concerned about
potentially source breaking changes with future versions of Kiota when updating the client.
Create the client application
Create a file in the root of the project named main.py and add the following code.
import asyncio
from kiota_abstractions.authentication.anonymous_authentication_provider import (
AnonymousAuthenticationProvider)
from kiota_http.httpx_request_adapter import HttpxRequestAdapter
from client.posts_client import PostsClient
from client.models.post import Post
async def main():
# You may need this if your're using asyncio on windows
# See: https://stackoverflow.com/questions/63860576
# asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())
# API requires no authentication, so use the anonymous
# authentication provider
auth_provider = AnonymousAuthenticationProvider()
# Create request adapter using the HTTPX-based implementation
request_adapter = HttpxRequestAdapter(auth_provider)
# Create the API client
client = PostsClient(request_adapter)
# GET /posts
all_posts = await client.posts.get()
print(f"Retrieved {len(all_posts)} posts.")
# GET /posts/{id}
specific_post_id = "5"
specific_post = await client.posts.by_post_id(specific_post_id).get()
print(f"Retrieved post - ID: {specific_post.id}, " +
f"Title: {specific_post.title}, " +
f"Body: {specific_post.body}")
# POST /posts
new_post = Post()
new_post.user_id = 42
new_post.title = "Testing Kiota-generated API client"
new_post.body = "Hello world!"
created_post = await client.posts.post(new_post)
print(f"Created new post with ID: {created_post.id}")
# PATCH /posts/{id}
update = Post()
# Only update title
update.title = "Updated title"
updated_post = await client.posts.by_post_id(specific_post_id).patch(update)
print(f"Updated post - ID: {updated_post.id}, " +
f"Title: {updated_post.title}, " +
f"Body: {updated_post.body}")
# DELETE /posts/{id}
await client.posts.by_post_id(specific_post_id).delete()
# Run main
asyncio.run(main())
Note
The JSONPlaceholder REST API doesn't require any authentication, so this sample uses the AnonymousAuthenticationProvider. For APIs that require authentication, use an applicable authentication provider.
Run the application
To start the application, run the following command in your project directory.
python3 main.py
See also
- kiota-samples repository contains the code from this guide.
- Microsoft Graph sample using Microsoft identity platform authentication
- ToDoItem Sample API implements a sample OpenAPI in ASP.NET Core and sample clients in multiple languages.