Explain the common technical complexities and patterns in integration development18% of the exam
API specifications, mocking and design-first development
What an API specification is and why designing it first pays off: the languages API Designer supports, the mocking service that lets consumers try an API before code exists, and sharing one contract through Exchange, Studio and API Manager.
Describe the purpose of an API specification and the benefits of following a design-first approach to API development.
~5 min read · 4 practice questions ·
What the exam expects
- Explain the purpose of an API specification as the structural plan, or contract, of an API.
- Describe the benefits of a design-first (spec-driven) approach, including the time it costs and the rework it saves.
- Name the specification languages API Designer supports.
- Explain how the mocking service lets consumers try an API before any implementation exists.
- Describe how one specification is shared through Exchange, Studio and API Manager.
Key terms:
- API specification: a plan of how the API should look structurally, like a blueprint of a house.
- Design-first (spec-driven development): designing and reviewing the specification before writing implementation code.
- API Designer: the Design Center web UI for writing specifications and RAML fragments.
- Mocking service: a continuously running service that returns the responses defined in a specification.
- Behavioral headers: request headers that change how the mocking service responds.
Key facts
Spec-driven time cost
- Detail
- Adds two to four weeks; can save months or years
RAML versions
- Detail
- 0.8 or 1.0 (specs and fragments)
OAS versions
- Detail
- 2.0 or 3.0
AsyncAPI versions
- Detail
- 2.0 and 2.6
Mock responses
- Detail
- Status codes and example payloads from the spec
Mock prerequisites
- Detail
- At least one endpoint, each with at least one method
MS2-Delay maximum
- Detail
- 10000 ms
Default mock status code
- Detail
- The minimum code defined for the method
- Why must an endpoint have at least one method before you can mock it?
- What happens to a shared public mocking URL if you disable and re-enable it?
- When the mock receives a request with no behavioral headers, which status code does it return?
- Which language must an API fragment use in API Designer?
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