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Native Binaries

When using the native binaries (not affecting the uberjar) there might be issues when using dynamic values in the configuration files. This is due to the fact that GraalVM only bundles whatever can discover at compile time. The following classes are currently supported:

  java.util.Base64.Encoder.class, java.util.Base64.Decoder.class, java.util.Base64.class,
org.apache.commons.lang3.RandomUtils.class, org.apache.commons.lang3.RandomStringUtils.class,
org.apache.commons.lang3.DateFormatUtils.class, org.apache.commons.lang3.DateUtils.class,
org.apache.commons.lang3.DurationUtils.class, java.time.LocalDate.class,

API specs

At this moment, CATS only works with OpenAPI specs and has limited functionality using template payloads through the cats fuzz ... subcommand.

Media types and HTTP methods

The Fuzzers have the following support for media types and HTTP methods:

  • application/json and application/x-www-form-urlencoded media types only
  • HTTP methods: POST, PUT, PATCH, GET and DELETE

Additional Parameters

If a response contains a free Map specified using the additionalParameters tag CATS will issue a warn log message as it won't be able to validate that the response matches the schema.

Regexes within 'pattern'

CATS uses RgxGen in order to generate Strings based on regexes. This has certain limitations mostly with complex patterns.