chapter four

4 APIs – The piping between our components

This chapter covers

Introduction to the FastAPI Framework
Documenting our APIs using the OpenAPI Standard
Testing our APIs using Postman and Locust
API Management with WSO2

An Application Program Interface (API) is simply a way to interact with a software component. Generally, when we speak about APIs we are talking about the REST (Representational State Transfer) API standard. However, there are other standards such as GraphQL and the older SOAP (Simple Object Access Protocol). We may also come across Message Queuing such as IBM Websphere MQ and RabbitMQ. Table 4.1 shows some pros and cons of the more common approaches to implementing APIs.

Table 4.1 Pros and Cons of different APIs

	REST	SOAP	GraphQL
Pros	Simple, builds upon standard HTTP methods Multiple data formats can be supported, although JSON is most common	Relies on XML based messaging Enterprise-level security	Efficient Single Endpoint Strongly typed
Cons	Versioning and breaking changes can be complex to manage Number of endpoints may become unwieldy	Complex to implement Verbose XML based messages	Steeper learning curve

4.1 API Driven Design

4.2 Our APIs

4.3 Building Our APIs with FastAPI

4.3.1 Getting files with /files

4.3.2 Adding a file with POST

4.3.3 Finishing the rest of the APIs

4.4 Adding our API to Docker

4.4.1 Preparing the project

4.4.2 Docker Setup

4.5 Documenting our API

4.5.1 Swagger

4.5.2 Redoc

4.6 Managing our APIs

4.6.1 Benefits of API Management

4.10 Summary