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OpenAPITools
openapi-generator
Java2018–2025
OpenAPITools / openapi-generator

openapi-generator

OpenAPI Generator allows generation of API client libraries (SDK generation), server stubs, documentation and configuration automatically given an OpenAPI Spec (v2, v3)

Systems & InfrastructureWeb DevelopmentLearning & ReferenceLibraries & SDKs
Explore on GitHubRead Hacker News discussions
43Distinct people
101Mentions
0Explicit recommenders
26.9KGitHub stars
REPOSITORY AT A GLANCE

What to know before exploring

What it is

OpenAPI Generator allows generation of API client libraries (SDK generation), server stubs, documentation and configuration automatically given an OpenAPI Spec (v2, v3)

GitHub

Where it is used

No documented product use was verified in the last source check.

What people are saying

No recommendation phrase was found in the indexed comments.

No classified warning is attached to this page. Read the discussions before treating silence as approval.

Also in these discussions

Mentioned in the same Hacker News threads. That is not proof they are substitutes.

This week on Hacker News

Nov 7–Nov 14 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/14/2026, 7:02:50 PM UTC.

No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.

Mentions over time

HN mentions by year101 dated mentions

Observed mentions: 2018-06-02 02:49:00 UTC to 2025-11-24 00:55:21 UTC.

01020302018-01-01 00:00:00 UTC to 2019-01-01 00:00:00 UTC (exclusive): 10 mentions; 5 submissions, 5 comments20182019-01-01 00:00:00 UTC to 2020-01-01 00:00:00 UTC (exclusive): 35 mentions; 25 submissions, 10 comments2020-01-01 00:00:00 UTC to 2021-01-01 00:00:00 UTC (exclusive): 15 mentions; 6 submissions, 9 comments2021-01-01 00:00:00 UTC to 2022-01-01 00:00:00 UTC (exclusive): 10 mentions; 2 submissions, 8 comments20212022-01-01 00:00:00 UTC to 2023-01-01 00:00:00 UTC (exclusive): 12 mentions; 4 submissions, 8 comments2023-01-01 00:00:00 UTC to 2024-01-01 00:00:00 UTC (exclusive): 5 mentions; 1 submissions, 4 comments2024-01-01 00:00:00 UTC to 2025-01-01 00:00:00 UTC (exclusive): 10 mentions; 2 submissions, 8 comments2025-01-01 00:00:00 UTC to 2026-01-01 00:00:00 UTC (exclusive): 4 mentions; 0 submissions, 4 comments2025

Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.

View mention counts and date ranges
UTC ranges include their start and exclude their end. Select a period to filter the source evidence.
PeriodStart (UTC)End (exclusive, UTC)MentionsSubmissionsComments
20182018-01-01 00:00:00 UTC2019-01-01 00:00:00 UTC1055
20192019-01-01 00:00:00 UTC2020-01-01 00:00:00 UTC352510
20202020-01-01 00:00:00 UTC2021-01-01 00:00:00 UTC1569
20212021-01-01 00:00:00 UTC2022-01-01 00:00:00 UTC1028
20222022-01-01 00:00:00 UTC2023-01-01 00:00:00 UTC1248
20232023-01-01 00:00:00 UTC2024-01-01 00:00:00 UTC514
20242024-01-01 00:00:00 UTC2025-01-01 00:00:00 UTC1028
20252025-01-01 00:00:00 UTC2026-01-01 00:00:00 UTC404

From the project README

An excerpt from the repository, fetched Nov 13, 2026.

Read the project’s introduction
OpenAPI Generator Master (7.28.0): ⭐⭐⭐ If you would like to contribute, please refer to guidelines and a list of open tasks. ⭐⭐⭐ ‼️ To migrate from Swagger Codegen to OpenAPI Generator, please refer to the migration guide ‼️ 📔 For more information, please refer to the Wiki page and FAQ 📔 📔 The eBook A Beginner's Guide to Code Generation for REST APIs is a good starting point for beginners 📔 ⚠️ If the OpenAPI spec, templates or any input (e.g. options, environment variables) is obtained from an untrusted source or environment, please make sure you've reviewed these inputs before using OpenAPI Generator to generate the API client, server stub or documentation to avoid potential security issues (e.g. code injection). For security vulnerabilities, please contact team@openapitools.org. ⚠️ ‼️ Both "OpenAPI Tools" (https://OpenAPITools.org - the parent organization of OpenAPI Generator) and "OpenAPI Generator" are not affiliated with OpenAPI Initiative (OAI) ‼️ Sponsors If you find OpenAPI Generator useful for work, please consider asking your company to support this Open Source project by becoming a sponsor. You can also individually sponsor the project by becoming a backer. Thank you to our bronze sponsors! Thank you GoDaddy for sponsoring the domain names, Linode for sponsoring the VPS, Checkly for sponsoring the API monitoring and Gradle for sponsoring Develocity Overview OpenAPI Generator allows generation of API client libraries (SDK generation), server stubs, documentation and configuration automatically given an OpenAPI Spec (both 2.0 and 3.0 are supported). Currently, the following languages/frameworks are supported: Languages/Frameworks API clients ActionScript, Ada, Apex, Bash, C, C# (.net 2.0, 3.5 or later, .NET Standard 1.3 - 2.1, .NET Core 3.1, .NET 5.0. Libraries: RestSharp, GenericHost, HttpClient), C++ (Arduino, cpp-restsdk, Qt5, Tizen, Unreal Engine 4), Clojure, Crystal, Dart, Elixir, Elm, Eiffel, Erlang, Go, Groovy, Haskell (http-client, Servant), Java (Apache HttpClient 4.x, Apache HttpClient 5.x, Jersey2.x, OkHttp, Retrofit1.x, Retrofit2.x, Feign, RestTemplate, RESTEasy, Vertx, Google API Client Library for Java, Rest-assured, Spring 5 Web Client, Spring 6 RestClient, MicroProfile Rest Client, Helidon), Jetbrains HTTP Client, Julia, k6, Kotlin, Lua, N4JS, Nim, Node.js/JavaScript (ES5, ES6, AngularJS with Google Closure Compiler annotations, Flow types, Apollo GraphQL DataStore), Objective-C, OCaml, Perl, PHP, PowerShell, Python, R, Ruby, Rust (hyper, reqwest, rust-server), Scala (akka, http4s, scalaz, sttp, swagger-async-httpclient, pekko), Swift (2.x, 3.x, 4.x, 5.x, 6.x), Typescript (AngularJS, Angular (9.x - 19.x), Aurelia, Axios, Fetch, Inversify, jQuery, Nestjs, Node, redux-query, Rxjs), XoJo, Zapier Server stubs Ada, C# (ASP.NET Core, Azure Functions), C++ (Httplib, Oat++, Pistache, Restbed, Qt5 QHTTPEngine), Erlang, F# (Giraffe), Go (net/http, Gin, Echo), Haskell (Servant, Yesod), Java (MSF4J, Spring, Undertow, JAX-RS: CDI, CXF, Inflector, Jersey, RestEasy, Play Framework, PKMST, Vert.x, Apache Camel, Helidon), Julia, Kotlin (Spring Boot, Ktor, Vert.x), PHP (Flight, Laravel, Lumen, Mezzio (fka Zend Expressive), Slim, Silex, Symfony), Python (FastAPI, Flask), NodeJS, Ruby (Sinatra, Rails5), Rust (rust-server), Scala (Akka, Finch, Lagom, Play, Cask, Scalatra) API documentation generators HTML, Confluence Wiki, Asciidoc, Markdown, PlantUML Configuration files Apache2 Others GraphQL, JMeter, Ktorm, MySQL Schema, Postman Collection, Protocol Buffer, WSDL Table of contents Sponsors Thank you to our bronze sponsors! Thank you GoDaddy for sponsoring the domain names, Linode for sponsoring the VPS, Checkly for sponsoring the API monitoring and Gradle for sponsoring Develocity Overview Table of contents 1 - Installation 1.1 - Compatibility 1.2 - Artifacts on Maven Central 1.3 - Download JAR Launcher Script 1.4 - Build Projects Nix users 1.5 - Homebrew 1.6 - Docker Public Pre-built Docker images OpenAPI Generator CLI Docker Image OpenAPI Generator Online Docker Image Development in docker Troubleshooting Run Docker in Vagrant 1.7 - NPM 1.8 - pip 2 - Getting Started 3 - Usage To generate a sample client library 3.1 - Customization 3.2 - Workflow Integration (Maven, Gradle, Github, CI/CD) 3.3 - Online OpenAPI generator 3.4 - License information on Generated Code 3.5 - IDE Integration 4 - Companies/Projects using OpenAPI Generator 5 - Presentations/Videos/Tutorials/Books 6 - About Us 6.1 - OpenAPI Generator Core Team Core Team Members Template Creator How to join the core team 6.2 - OpenAPI Generator Technical Committee Members of Technical Committee 6.3 - History of OpenAPI Generator Founding Members (alphabetical order): 7 - License 1 - Installation 1.1 - Compatibility The OpenAPI Specification has undergone 3 revisions since initial creation in 2010. The openapi-generator project has the following compatibilities with the OpenAPI Specification: OpenAPI Generator Version Release Date Notes 7.28.0 (upcoming minor release) SNAPSHOT 20.11.2026 Minor release with breaking changes (with fallback) 7.27.0 (latest stable release) 02.11.2026 Minor release with breaking changes (with fallback) 6.6.0 11.05.2023 Minor release with breaking changes (with fallback) 5.4.0 31.01.2022 Minor release with breaking changes (with fallback) 4.3.1 06.05.2020 Patch release (enhancements, bug fixes, etc) OpenAPI Spec compatibility: 1.0, 1.1, 1.2, 2.0, 3.0, 3.1 (beta support) (We do not publish daily/nightly build. Please use SNAPSHOT instead) For old releases, please refer to the Release page. For decommissioned generators/libraries/frameworks, please refer to the "Decommission" label in the pull request page. 1.2 - Artifacts on Maven Central You can find our released artifacts on maven central: Core: <dependency> <groupId>org.openapitools</groupId> <artifactId>o
Read the full README on GitHub

What Hacker News says

15 sources
wing328hk·Nov 15, 2020
FYI. OpenAPI Generator supports many programming languages and server-side frameworks: https://github.com/OpenAPITools/openapi-generator#overview This is not to say it has more languages supported than Protobuf as I do not know exactly how many generators out there supporting Protobuf. (OpenAPI Generator also comes with the generator/converter that converts OpenAPI spec documents into gRPC and protocol buffer schema files. Not sure if OpenAPI Generator is also counted as a generator for Protobuf)
In API design is stuck in the past
wing328hk·Nov 15, 2020
> Does OpenAPI generate code for you? I have worked on projects that use it and didn't have any generated code, so I am assuming not... Please give OpenAPI Generator [1] a try to generate clients, servers stubs, documentation, schemas (graphql, protobuf, etc) and more. It supports many programming languages and many companies are already using it [2]: [1] https://github.com/OpenAPITools/openapi-generator [2] https://openapi-generator.tech/users (Disclosure: I'm the top contributor to OpenAPI Generator)
In API design is stuck in the past
wing328hk·May 5, 2020Submission

Show HN: Auto-generate ASP.NET Core servers stub for REST APIs

We've added ASP.NET Core 3.1 & 3.0 support to OpenAPI Generator (https://github.com/OpenAPITools/openapi-generator). To generate the ASP.NET Core server stub given an OpenAPI/Swagger specification file, please follow 3 simple steps below: 1. Download the Java JAR (https://oss.sonatype.org/content/repositories/snapshots/org/openapitools/openapi-g…) 2. Rename the JAR as "openapi-generator-cli.jar" 3. Run the following command to generate a ASP.NET Core server stub for the Petstore API (https://raw.githubusercontent.com/OpenAPITools/openapi-generator/master/modules/op…): Mac/Linux: - java -jar openapi-generator-cli.jar generate -g aspnetcore -i https://raw.githubusercontent.com/OpenAPITools/openapi-generator/master
Read the rest
/modules/openapi-generator/src/test/resources/3_0/petstore.yaml -o /var/tmp/aspnetcore31/ --additional-properties aspnetCoreVersion=3.1 Windows: - java -jar openapi-generator-cli.jar generate -g aspnetcore -i https://raw.githubusercontent.com/OpenAPITools/openapi-generator/master/modules/op… -o C:\tmp\aspnetcore31 --additional-properties aspnetCoreVersion=3.1 Thanks Paul Hatcher (https://github.com/phatcher) for contributing the enhancement (https://github.com/OpenAPITools/openapi-generator/pull/6025). If you've any feedback or question, please let us know via https://github.com/OpenAPITools/openapi-generator/issues/new.
1 points · Open discussion
wing328hk·Mar 4, 2020Submission

Show HN: Auto-Generate Scala API Clients for REST APIs

We've added a new generator to OpenAPI Generator (https://github.com/OpenAPITools/openapi-generator) to generate Scala (sttp - https://github.com/softwaremill/sttp) API clients. To generate the client given an [OpenAPI/Swagger specification file](https://github.com/OAI/OpenAPI-Specification), please follow 3 simple steps below: 1. Download the Java JAR: https://oss.sonatype.org/content/repositories/snapshots/org/openapitools/openapi-g… 2. Rename the JAR as "openapi-generator-cli.jar" 3. Run the following command to generate a Scala (sttp) API client for the Petstore API: https://raw.githubusercontent.com/OpenAPITools/openapi-generator/master/modules/op… Mac/Linux: $ java -jar openapi-generator-cli.jar generate -
Read the rest
g scala-sttp -i https://raw.githubusercontent.com/OpenAPITools/openapi-generator/master/modules/op… -o /var/tmp/scala-sttp/ Windows: $ java -jar openapi-generator-cli.jar generate -g scala-sttp -i https://raw.githubusercontent.com/OpenAPITools/openapi-generator/master/modules/op… -o C:\tmp\scala-sttp If you've any feedback or question, please let us know via https://github.com/OpenAPITools/openapi-generator/issues/new. The new generator will be included in the upcoming v4.3.0 stable release. Thanks for the new generator by Aleksandr Nekrasov (https://github.com/chameleon82) Ref: https://github.com/OpenAPITools/openapi-generator/pull/5429
4 points · Open discussion
wing328hk·Feb 25, 2020
If you want to access RESTful APIs via OCaml, you may consider using OpenAPI Generator to generate the OCaml client automatically instead of manually creating one. Here are 3 simple steps to do so: 1. Download the OpenAPI Generator CLI Java JAR (https://repo1.maven.org/maven2/org/openapitools/openapi-gene...) 2. Rename the JAR as "openapi-generator-cli.jar" 3. Run the following command to generate an OCaml API client for the Petstore API (https://raw.githubusercontent.com/OpenAPITools/openapi-gener...): Mac/Linux: $ java -jar openapi-generator-cli.jar generate -g ocaml -i https://raw.githubusercontent.com/OpenAPITools/openapi-gener... -o /var/tmp/ocaml/ Windows: $ java -jar openapi-generator-cli.jar generate -g ocaml -i https://raw.githubusercontent.com/OpenAPITools/openapi-gener... -o C:\tmp\ocaml If you've any feedback or question, plea
Read the rest
se let us know via https://github.com/OpenAPITools/openapi-generator/issues/new
In Functional Programming in OCaml
wing328hk·Feb 21, 2020
Do you mind opening an issue via http://github.com/OpenAPITools/openapi-generator/issues/new with the details? (I assumed you've checked out the auto-generated documentation and that doesn't look good to you.) There were discussions on type hints but unfortunately no one has found the time to make the contribution yet. We also have a new `python-experimental` client generator that has better support for new features in OAS v3. Please check it out to see if it works better for you.
In OpenAPI 3.0.3 Specification Released
hardwaresofton·Feb 21, 2020
For those who don't know already -- one of the best parts about the OpenAPI spec is that it allows generation of the clients and servers and the OpenAPITools/openapi-generator[0] is the tool that does that effortlessly. If you want to take your CI pipeline to the next level you can run it (dockerized, if you want) from a CI step to generate and commit + tag a completely separate repo to have your API SDK generation completely automated. I've written a little about the dumbest possible way you could do it (i.e. manually writing YAML)[1] for when you don't have proper framework support. openapi-generator also has some really awesome new features and support for different languages, most recent big release was 4.0 (and most recent as of this post is 4.2.3)[2], been meaning to write a bit about that as well since their haskell support gets be
Read the rest
tter and better every time. Super awesome & convenient project, the value being delivered for free is unreal. [0]: https://github.com/OpenAPITools/openapi-generator [1]: https://vadosware.io/post/quick-intro-to-manual-openapi-v3/ [2]: https://github.com/OpenAPITools/openapi-generator/releases
In OpenAPI 3.0.3 Specification Released

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