RestTestGen v2

A framework for automated black-box testing of RESTful APIs.

v2: this is a re-implementation of the original tool proposed by our research team in 2020. This new version is implemented as a framework that allows researchers and practitioners to implement their own testing strategy on top of our core. Testing strategies presented in our papers are included, and available in the io.resttestgen.implementation package.

Citing our work: bibtex entries for our papers are available in the CITE.md file.

The core of the RestTestGen framework provides the following features:

custom parser for OpenAPI specifications v3 in JSON format (we dropped Swagger Codegen that caused instability)
- please convert Swagger 2.0 files or YAML specifications to JSON v3 specification using https://editor.swagger.io/
- combined parameter schemas (OneOf, AllOf, AnyOf) are supported by the parser, but currently not used in our strategies (wip)
the Operation Dependency Graph (ODG), that models data dependencies among operations
dictionaries storing values observed at testing time
smart parameter management using hierarchical data structures
- these data structures are automatically converted to HTTP requests
fuzzers to generate parameter values
mutation operators
- data type mutation operator
- missing required mutation operator
- constraint violation mutation operator
response processors to elaborate responses
operations sorters to provide customized operations testing ordering
- random sorter
- ODG-based dynamic sorter
oracles to evaluate test executions
- nominal status code oracle
- error status code oracle
- schema validation oracle (wip)
writers to output test cases and test results to file
- JSON report writer
- JUnit + OkHttp test case writer (wip)
- JUnit + REST Assured test case writer
coverage measurements
- path coverage
- operations coverage
- status code coverage
- parameter coverage
- parameter value coverage

Changelog

v23.01

Added mass assignment vulnerability detection security testing strategy (beta). (Add "strategyName": "MassAssignmentSecurityTestingStrategy" to the configuration file to use this strategy).

For the changelog of past versions see the CHANGELOG.md file.

Requirements

Java 11
Ubuntu, or other Linux distributions (RestTestGen was not tested on Windows)

For further information see the REQUIREMENTS.md file.

Configuration

RestTestGen comes with a built-in default configuration suitable for most REST APIs, defined in the io.resttestgen.core.Configuration class. The default configuration can be overridden by means of the rtg_config.json file. The file must be located in the current working directory.

Configurable preferences:

logVerbosity: the verbosity of the log. Can be DEBUG, INFO, WARN, or ERROR (default: INFO)
testingSessionName: the name of the testing session printed in the report files (default: test-session-CURRENT_TIME)
outputPath: the path in which output data is written (default: output/)
specificationFileName: the file name of the input OpenAPI specification (default: openapi.json)
authCommand: command to be run to gather information about authentication. See Authentication (default: none)
strategyName: the name of the testing strategy class to be run. NominalAndErrorStrategy or your own strategy class (default: NominalAndErrorStrategy)
qualifiableNames: list of parameter names to be qualified. E.g., id -> petId, name -> petName (default: ['id', 'name'])
odgFileName: output file name for the operation dependency graph (default: odg.dot)

We suggest to override only the strictly necessary preferences, typically the file name of the OpenAPI specification, and the authentication command.

Specific preferences to the nominal and error testing strategy are at the moment only customizable in the source code.

Example of a configuration file (rtg_config.json):

{
  "specificationFileName": "path/to/my/specification.json",
  "authCommand": "python auth.py",
  "strategyName": "NominalAndErrorStrategy",
  "testingSessionName": "customNameForTestingSession",
  "outputPath": "output/"
}

Authentication

(skip if your REST API does not require authentication)

RestRestGen supports authenticated REST APIs. To gather authentication information, RestTestGen runs the authentication command (if provided in the configuration), whose output is expected to be a JSON array. Objects in the array are authentication parameters: they have a name, a value, a location (header, query, etc.), and a timeout (the authentication command will be re-executed, e.g., to gather a new token, after the timeout). The current version of RestTestGen only supports 1 parameter (the first one in the array). Other parameters are currently ignored.

Example of the output of the authentication command:

[
  {
    "name": "Authorization",
    "value": "Bearer [TOKEN]",
    "in": "header",
    "timeout": 600
  }
]

This output is generated by an example python script auth.py, which authenticates a user with the REST API through HTTP interactions. In this example the authentication command for RestTestGen is python path/to/auth.py.

Building and running RestTestGen

To build and run RestTestGen with Gradle use the command: ./gradlew run

Alternatively, you can open the RestTestGen Gradle project with IntelliJ IDEA. To run RestTestGen, click the play icon alongside the main method of the class io.resttestgen.core.cli.App.

Warning: make sure that your gradlew file is executable. Moreover, some test cases only work with the default OpenAPI specification, so in the case the execution fails due to failed test cases, we recommend to skip tests adding -x test to Gradle commands.

Contributing

Contributions by researchers, practitioners, and developers are welcome.

To extend the RestTestGen framework and its core components, please contribute in the io.resttestgen.core package. If you are developing a novel testing strategy, please contribute in the io.resttestgen.implementaion package.

Please submit your contribution by means of a pull request. Thank you!