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RestTestGen

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What RestTestGen is

RestTestGen is a free, open-source framework for automated black-box, end-to-end testing of RESTful web APIs over HTTP. It requires an OpenAPI v3 specification in JSON or YAML and a deployed API reachable over HTTP. Strategies cover nominal and error testing, mass-assignment security testing, natural-language enhancement of specifications, and DeepREST reinforcement learning. The framework generates parameter values, applies mutation operators, processes responses, and sorts operations through configuration. It offers status-code and security oracles, coverage measurements, reports, and replayable JUnit and REST-assured test cases. RestTestGen can run through Docker, Gradle, or IntelliJ IDEA, with a dedicated Dockerfile for DeepREST. The maintainers recommend Ubuntu and report testing the current version on Ubuntu 22.04 LTS; Gradle use requires Java 11. Its Docker container includes Java 11 and Gradle 8.14 but not Python, which authentication scripts may need. Authenticated tests use user-provided commands returning authentication parameters as JSON, one command at a time. The project is licensed under Apache License 2.0.

Who it suits

RestTestGen suits researchers, practitioners, and developers testing HTTP APIs from OpenAPI specifications. It is relevant to teams needing generated tests, coverage and reports, security checks, or replayable JUnit and REST-assured cases.

What it does well

  • Free Apache-2.0 framework
  • OpenAPI v3 JSON and YAML
  • Security testing strategy
  • Coverage and replayable tests
  • Docker, Gradle, IntelliJ options

What to know first

  • Requires deployed HTTP API
  • Docker image excludes Python
  • Gradle requires Java 11
  • NLP strategy needs separate service

Plans

PlanBilled and limitsPrice
RestTestGenApache-2.0 licensed open-source frameworkFree

As github.com lists them, read 5 Oct 2026. The maker's own page has the final word.

Verdict

RestTestGen provides broad API test-generation and analysis options without a software charge. Plan for its OpenAPI and deployed-instance requirements, runtime dependencies, and separate NLP2REST service when applicable.

Facts from RestTestGen's own pages

Analysis and output
It provides status-code and security oracles, coverage measurements, reports, and replayable JUnit plus REST-assured test cases. · github.com, 5 Oct 2026
API requirement
Testing an API requires its OpenAPI specification and a deployed instance reachable over HTTP. · github.com, 5 Oct 2026
Audience and support
The maintainers describe the framework as intended for researchers, practitioners, and developers, and invite contributions through pull requests. · github.com, 5 Oct 2026
Authentication
Authenticated API testing uses user-provided commands that return authentication parameters as JSON, and only one command is used at a time. · github.com, 5 Oct 2026
Deployment
The project can be built and run with Docker, Gradle, or IntelliJ IDEA; DeepREST has a dedicated Dockerfile. · github.com, 5 Oct 2026
Docker limitation
The RestTestGen Docker container includes Java 11 and Gradle 8.14 but does not include Python, which may be needed by user authentication scripts. · github.com, 5 Oct 2026
Founded
2022 · github.com, 28 Sept 2026
Integration
The NLP-based specification enhancement strategy requires a separately deployed NLP2REST Rule Extraction service. · github.com, 5 Oct 2026
OpenAPI support
The framework parses OpenAPI v3 specifications in JSON and YAML formats. · github.com, 5 Oct 2026
Purpose
RestTestGen is a framework and tool for automated black-box end-to-end testing of RESTful web APIs over HTTP. · github.com, 5 Oct 2026
Security and license
The repository is licensed under Apache License 2.0; its included mass assignment strategy tests for that vulnerability class. · github.com, 5 Oct 2026
Strategies
Included strategies cover nominal and error testing, mass assignment security testing, natural-language enhancement of OpenAPI specifications, and DeepREST reinforcement learning. · github.com, 5 Oct 2026
System requirements
The maintainers recommend Ubuntu and report testing the current version on Ubuntu 22.04 LTS; running with Gradle requires Java 11. · github.com, 5 Oct 2026
Test generation
It supports parameter value generation and retrieval, mutation operators, response processors, and configurable operation sorting. · github.com, 5 Oct 2026

Where RestTestGen stands on Freedom251

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