CATS documentation is available at https://endava.github.io/cats/

REST API fuzzer and negative testing tool. Run thousands of self-healing API tests within minutes with no coding effort!

• Comprehensive: tests are generated automatically based on a large number scenarios and cover every field and header
• Intelligent: tests are generated based on data types and constraints; each Fuzzer has specific expectations depending on the scenario under test
• Highly Configurable: high amount of customization: you can filter specific Fuzzers, HTTP response codes, HTTP methods, request paths, provide business context and a lot more
• Self-Healing: as tests are generated, any OpenAPI spec change is picked up automatically
• Simple to Learn: flat learning curve, with intuitive configuration and syntax
• Fast: automatic process for write, run and report tests which covers thousands of scenarios within minutes

Short on time? Check out the 1-minute Quick Start Guide!

Overview

By using a simple and minimal syntax, with a flat learning curve, CATS (Contract Auto-generated Tests for Swagger) enables you to generate thousands of API tests within minutes with no coding effort. All tests are generated, run and reported automatically based on a pre-defined set of 98 Fuzzers. The Fuzzers cover a wide range of boundary testing and negative scenarios from fully random large Unicode values to well crafted, context dependant values based on the request data types and constraints. Even more, you can leverage the fact that CATS generates request payloads dynamically and write simple end-to-end functional tests.

Tutorials on how to use CATS

This is a list of articles with step-by-step guides on how to use CATS:

• Testing the GitHub API with CATS
• How to write self-healing functional tests with no coding effort

Some bugs found by CATS

• hashicorp/vault#13274 | hashicorp/vault#13273
• hashicorp/vault#13225 | hashicorp/vault#13232
• go-gitea/gitea#19397 | go-gitea/gitea#19398
• go-gitea/gitea#19399

Installation

Homebrew

> brew tap endava/tap
> brew install cats

Manual

CATS is bundled both as an executable JAR or a native binary. The native binaries do not need Java installed.

After downloading your OS native binary, you can add it to PATH so that you can execute it as any other command line tool:

sudo cp cats /usr/local/bin/cats

You can also get autocomplete by downloading the cats_autocomplete script and do:

source cats_autocomplete

To get persistent autocomplete, add the above line in .zshrc or .bashrc, but make sure you put the fully qualified path for the cats_autocomplete script.

You can also check the cats_autocomplete source for alternative setup.

There is no native binary for Windows, but you can use the uberjar version. This requires Java 17+ to be installed.

You can run it as java -jar cats.jar.

Head to the releases page to download the latest version: https://github.com/Endava/cats/releases.

Contributing

Please refer to CONTRIBUTING.md.