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Institute of Advanced Technological and Commercial Studies

Glossary

Application programming interface: the contract between two programs

An application programming interface, known as an API, defines how one program exposes its services to another. It sets the requests accepted, the responses returned and the access rules. As long as that contract holds, both programs evolve independently.

A contract between two programs

An application programming interface describes the services a program makes available: each operation, its parameters, its response and its access conditions. It forms a contract: as long as it holds, the two programs evolve independently. That is what lets a mobile app, a website and a management system share the same data without knowing each other.

  • Every operation states its parameters and its response
  • Access is authenticated and logged, call by call
  • A versioned contract lets both programs evolve separately

What an interface must state

The Web and Mobile Development programme has candidates design a complete interface, from defining the operations to documentation a third party can read unaided. The Computer Science programme approaches it from the foundations: data model, access control and the errors returned to the caller.

The operations

What the interface allows, named one by one, with the parameters expected.

The responses

The format returned and the status code, including for the cases the caller must handle.

Authentication

Who calls, with what right, and how the key is renewed without interrupting service.

Versioning

How a change is introduced while existing callers keep working.

Programmes that have you build one

2 catalogue programmes put “Application programming interface” to work: 300 credits and 3000 taught hours in total. The official rule holds throughout — one credit stands for 25 hours of work, 10 of them taught. Every line below is recomputed from the programme page: level, duration, credits, taught volume and fees in Guinean francs appear exactly as filed in the official catalogue.

ProgrammeLevelDurationVolumeFees
Web and Mobile DevelopmentBachelor's degree2 years120 credits · 1200 taught hours5 200 000 GNF per year
Computer Science programme — Bac+3 levelBachelor's degree3 years180 credits · 1800 taught hours5 400 000 GNF per year
Application programming interface: the contract between two programs — Glossary | IHETC — IHETC