Organizing a project based on dependencies
It is feasible to use a repository-service pattern in some complex FastAPI applications through DI. The repository-service pattern is responsible for the creation of the repository layer of the application, which manages the Creation, Reading, Updates, and Deletion (CRUD) of data source. A repository layer requires data models that depict the table schemas of a collection or database. The repository layer needs the service layer to establish a connection with other parts of the application. The service layer operates like a business layer, where the data sources and business processes meet to derive all the necessary objects needed by the REST API. The communication between the repository and service layers can only be possible by creating injectables. Now, let us explore how the layers shown in Figure 3.2 are built by DI using injectable components.
Figure 3.2 – The repository-service layers
