SOAP Testing
SOAP testing verifies APIs built on the SOAP protocol — an XML-based messaging standard with a strict, formally defined contract (WSDL) — checking that requests and responses conform to that contract and that the service handles the protocol's built-in error and fault-handling conventions correctly.
SOAP predates REST and remains common in enterprise, financial, and legacy government systems specifically because of its strict, machine-verifiable contract (the WSDL file), built-in security standards (WS-Security), and formal error handling (SOAP Faults) — properties some regulated industries still value over REST's comparative flexibility.
Because the WSDL describes the entire API contract formally, testing tools like SoapUI can generate test requests directly from it automatically, and validate responses against the same formal schema — similar in spirit to JSON Schema validation for REST, but built into the protocol itself from the start.
