"Orchestration describes how web services interact with each other at the message level, including the business logic and execution order of the interactions" [Chris Peltz 2003]. These interactions may span applications and/or organizations, and result in a longlived, transactional, multi-step process model. For example, in the eLandings web services interface /wiki/spaces/et/pages/8454262, the simplest case of reporting a landing requires a minimum of the following web service method invocations:
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In order to support integration with third party systems these details of message sequences and conventions must be explicitly documented and there should be test suites plans specified for a number of common transactional processes, including:
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After execution of any of these specific steps, it must be possible to compare the resulting state to the expected state, to provide feedback and identify any discrepancies.
Resources
Advice on test planning and documentation for manual system testing.
Tigris.org Words of Wisdom re Test Cases
Tigris.org Test Case Format
Tigris.org Test Suite