Software Alternatives, Accelerators & Startups

OpenAPI Generator VS FastAPI

Compare OpenAPI Generator VS FastAPI and see what are their differences

OpenAPI Generator logo OpenAPI Generator

OpenAPI Generator enables you to generate documentation, clients, and servers from OpenAPI 2.0/3.x documents without hassle.

FastAPI logo FastAPI

FastAPI is an Open Source, modern, fast (high-performance), web framework for building APIs with Python 3.6+ based on standard Python type hints.
  • OpenAPI Generator Landing page
    Landing page //
    2023-03-01
  • FastAPI Landing page
    Landing page //
    2023-05-14

OpenAPI Generator features and specs

  • Wide Language Support
    OpenAPI Generator supports a broad range of programming languages, which allows developers to generate client libraries, server stubs, API documentation, and other code artifacts across various languages with ease.
  • Customizability
    The tool provides diverse customization options, including custom templates, configuration options, and overrides, enabling developers to tailor the generated code to meet specific project requirements.
  • Active Community
    OpenAPI Generator benefits from an active and engaged community that contributes to continuous improvements, bug fixes, and enhancements, ensuring the tool stays updated with evolving needs and standards.
  • Comprehensive Documentation
    It comes with extensive documentation and a rich set of resources that help users understand how to leverage the tool effectively for their projects.
  • Time-Efficiency
    Automating the generation of API-related code significantly reduces development time and effort, allowing teams to focus on implementing business logic rather than boilerplate code.

Possible disadvantages of OpenAPI Generator

  • Complexity
    Although powerful, OpenAPI Generator can be complex to configure and use effectively, especially for newcomers unfamiliar with OpenAPI specifications and generation nuances.
  • Generated Code Quality
    While the tool generates a significant amount of code, the quality of the generated code might not always match hand-crafted solutions, potentially requiring manual refinements and adjustments.
  • Heavy Dependency
    Relying on a code generator creates a dependency on the tool, which may complicate upgrades over time, especially if custom templates or configurations are heavily used.
  • Learning Curve
    There is a learning curve associated with understanding the OpenAPI specification and how to effectively use the generator, particularly for complex APIs and integrations.
  • Maintenance Overhead
    Keeping up with new releases and ensuring compatibility with updated OpenAPI standards can introduce additional maintenance overhead for teams using the tool extensively.

FastAPI features and specs

  • High Performance
    Built on Starlette and Pydantic, FastAPI is one of the fastest frameworks for Python, providing high performance due to its asynchronous request handling.
  • Automatic Interactive API Documentation
    FastAPI automatically generates interactive API documentation via Swagger UI and ReDoc, which are very helpful for development and testing.
  • Type Checking and Validation
    With Pydantic models and Python type hints, FastAPI provides automatic data validation and type checking, reducing the chance of runtime errors.
  • Ease of Use
    Its syntax and design make it easy to learn for Python developers, offering a smooth development experience while reducing boilerplate code.
  • Asynchronous Support
    FastAPI supports asynchronous programming, allowing for better performance for I/O-bound operations, making it optimal for handling many simultaneous connections.
  • Extensive Documentation
    It has comprehensive and well-structured documentation, which is very useful for both beginners and advanced users.
  • Community and Ecosystem
    FastAPI has a growing community and ecosystem, with many plugins and integrations available to extend its functionality.

Possible disadvantages of FastAPI

  • Learning Curve for Asynchronous Programming
    Although FastAPI itself is easy to learn, grasping the concepts of asynchronous programming in Python can be challenging for beginners.
  • Complex Dependencies
    Using Pydantic for advanced validation can make the request models complex, requiring a deeper understanding of Pydantic and its functionalities.
  • Early Stage Libraries
    Some third-party libraries and extensions specifically tailored for FastAPI might still be in early stages of development and lack long-term stability.
  • Limited Real-World Examples
    Although the documentation is extensive, there might be limited real-world examples and case studies readily available compared to more mature frameworks.
  • Deployment Complexity
    Deploying FastAPI applications might be more complex in comparison to traditional synchronous frameworks, mainly due to the need for asynchronous server setups.

Analysis of FastAPI

Overall verdict

  • FastAPI is widely regarded as a good choice, especially for applications that require high performance, scalability, and modern Python features. It is suitable for both simple and complex projects, making it a versatile tool in the web development ecosystem.

Why this product is good

  • FastAPI is a modern, fast (high-performance), web framework for building APIs with Python 3.7+ based on standard Python type hints. It is built on top of Starlette for web framework capabilities and Pydantic for data validation and settings management. FastAPI is known for its excellent performance, automatic generation of interactive API documentation (with Swagger and Redoc), and support for asynchronous programming. Developers appreciate its ease of use, detailed documentation, and helpful error messages.

Recommended for

  • Developers building RESTful APIs
  • Teams looking for a high-performance ASGI-based web framework
  • Projects that require asynchronous programming capabilities
  • Applications needing automatic generation of interactive API documentation
  • Python developers who prefer utilizing type hints for code clarity and validation

OpenAPI Generator videos

Introducing OpenAPI Generator

More videos:

  • Review - Scaling the Test Coverage of OpenAPI Generator for 30+ Programming Languages - William Cheng

FastAPI videos

FastAPI from the ground up

More videos:

  • Tutorial - 30 Days of Python - Day 14 - Web App with Flask, FastAPI, ngrok, and Invictify - Python TUTORIAL
  • Review - [PT] Python - API com FastAPI - Chat | twitch.tv/codeshow

Category Popularity

0-100% (relative to OpenAPI Generator and FastAPI)
Development
100 100%
0% 0
Developer Tools
9 9%
91% 91
API Tools
0 0%
100% 100
Tool
100 100%
0% 0

User comments

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Reviews

These are some of the external sources and on-site user reviews we've used to compare OpenAPI Generator and FastAPI

OpenAPI Generator Reviews

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FastAPI Reviews

  1. Kurslog team
    ยท Working at Kurslog ยท

    When our backend team needs to build services for data parsing, aggregators, or high-load APIs, FastAPI is our absolute go-to choice. It completely lives up to its name-development speed is outstanding.

    The combination of Pydantic for data validation and built-in async support keeps our shared codebase clean, strictly typed, and reliable. But the biggest highlight for our cross-functional team is the automatic generation of interactive OpenAPI (Swagger) documentation. Our frontend and mobile developers no longer have to wait for backend engineers to manually update API docs; everything stays perfectly in sync automatically. It has drastically improved our team's communication and delivery speed.

    ๐Ÿ Competitors: Django, Flask, ExpressJS, Nest.js, Spring Boot
    ๐Ÿ‘ Pros:    Blazing fast performance (on par with nodejs and go)|Native asynchronous support out of the box|Automatic, interactive documentation generation (swagger/redoc)|Strict typing and data validation with pydantic
    ๐Ÿ‘Ž Cons:    Smaller plug-and-play ecosystem compared to older frameworks like django|Requires our architects to design the project structure and directory layout from scratch

The 20 Best Laravel Alternatives for Web Development
FastAPI, as the name hints, is a swift mover. Built on Starlette, itโ€™s all about speed and performance with Python. Crafting API masterpieces at the speed of light, now thatโ€™s something.
25 Python Frameworks to Master
Since its release in 2018, it has rapidly gained popularity due to its great performance and simplicity. In fact, according to PyPi Stats, FastAPI has over 9 million monthly downloads, surpassing even full-stack frameworks like Django.
Source: kinsta.com
3 Web Frameworks to Use With Python
myapp/ is the main directory of your FastAPI application. It includes all the other files and directories needed for the application.static/ is a directory used to store static assets such as CSS, JavaScript, and image files. These assets are served directly by the web server and are typically used to add visual styling and interactivity to the application.css/, img/, js/...
Best Alternatives to FastAPI App Free for Windows (2021)
FastAPI Alternative โ€“ So many alternatives app to FastAPI that you must to know out there. And, looking for an ideal software was not easy matter. Lucky you, at this page you can find the best replacement app for FastAPI. So what you are waiting for, get the latest FastAPI alternative app for Windows 10 from this page.
Top 5 Back-End Frameworks to Consider for Web Development in 2021
FastAPI is a modern, fast (high-performance), web framework for building APIs with Python 3.6+ based on standard Python type hints. It is fast when compared to other major Python frameworks like Flask and Django. FastAPI gives great flexibility to fulfill businessesโ€™ API needs in todayโ€™s evolving world.

Social recommendations and mentions

Based on our record, FastAPI should be more popular than OpenAPI Generator. It has been mentiond 311 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.

OpenAPI Generator mentions (45)

  • Stop Advertising in Your Commits
    To be fair I've never used Laravel - but I do have a memory of code generators/scaffolders inserting files that made clear they were responsible for work /* * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech). * Do not edit the class manually. */. - Source: Hacker News / about 2 months ago
  • From Swagger UI to React: Building qcontroller's Frontend
    For the REST API communication, I leveraged OpenAPI Generator to automatically generate TypeScript client code. This API-first approach eliminates the common frontend-backend synchronization problems and ensures type safety across the entire stack. - Source: dev.to / 6 months ago
  • How and Why to Use Patches
    Patches are also useful if we're making manual modifications to any codebase that is being auto-generated, i.e. If we're using openapi-generator off of an OpenAPI spec to create clients and scaffolded server codebases. We would want to maintain the patch as a way to ensure that subsequent re-generations of the code don't wipe out any manual changes we have to make in-between. - Source: dev.to / about 1 year ago
  • Using OpenAPI to Automate API Integration With Rapyd's Payment Gateway
    Manually writing API clients can be time-consuming and result in errors. This is where the OpenAPI specification and tools like OpenAPI Generator are helpful. - Source: dev.to / over 1 year ago
  • Define, Generate, and Implement: An API-First Approach with OpenAPI Generator and FlightPHP
    With your API defined, use the OpenAPI Generator to generate your code automatically. The PHP Flight generator โ€” documented here โ€” was provided by the author and, although its status is still marked as "experimental", it has been my production workhorse for over a year. - Source: dev.to / over 1 year ago
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FastAPI mentions (311)

  • Shipping Sovereign SDK: Cryptographic Forensic Receipts and the End of the AI "Prose Tax"
    The Sovereign SDK is a Python-native framework designed to minimize prose overhead while generating ironclad, cryptographic execution receipts for AI agents, complete with drop-in FastAPI/Starlette ASGI middleware. - Source: dev.to / about 2 months ago
  • 5-Minute AI Jobs and Closed Tabs โ€” Why We Built Replay-Then-Tail SSE
    We had a feature in production where a single user request could run for five-plus minutes โ€” fetch documents, chunk them, hit an LLM per chunk, synthesize a final answer. We did the obvious thing first: a FastAPI handler that ran the pipeline and streamed progress back to the browser over Server-Sent Events. - Source: dev.to / 3 months ago
  • FastAPI With LangChain and MongoDB
    FastAPI is a Python framework for building APIs quickly, efficiently, and with very little code. - Source: dev.to / 3 months ago
  • I Built A " CrowdSense AI " : A Scalable, Context-Aware Platform for Smart Stadiums
    Backend: Python-based FastAPI for its asynchronous I/O capabilities and rapid JSON serialization. - Source: dev.to / 3 months ago
  • Async PyMongo in FastAPI
    FastAPI is a high-performance web framework that is production-ready and designed for building APIs in python, with roots embedded in asynchronous programming. It embraces Pythonโ€™s asyncio model as its core principle rather than treating it as optional. This design choice gives FastAPI leverage for I/O bound workloads such as db access, external API calls and real-time data streaming. - Source: dev.to / 3 months ago
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What are some alternatives?

When comparing OpenAPI Generator and FastAPI, you can also consider the following products

Widdershins - Widdershins is an open-source, easy to use Semoasa/ OpenAPI/ AsyncAPI/ definition to ReSlate/Slate compatible markdown released under the MIT License.

Flask - a microframework for Python based on Werkzeug, Jinja 2 and good intentions.

API Transformer - API Transformer is a powerful solution that enables you to Transform API specifications to any format.

ExpressJS - Sinatra inspired web development framework for node.js -- insanely fast, flexible, and simple

API Spec Converter - API Spec Converter is an open-source solution that enables you to transform API descriptions between major formats like WADL, OpenAPI (fka Swagger), API Blueprint, RAML, and more.

Django - The Web framework for perfectionists with deadlines