CAP OData

This CAP Node.js Project is used to access an OData Service (Northwind used here), get Entity Data (Product used here) and store it in a SQLite persisted DB.

Steps to get Product Data

1. Complete the local setup mentioned here.
2. Initialize CAP project with cds init command.
3. Download metadata of the northwind service as a .edmx file anywhere in your system.
4. Import the metadata using cds import [filepath.edmx]. This creates a .csn and a .edmx file in /src/external folder. It also creates a cds.requires entry for the Northwind service in package.json.
5. Create the catalog-service.cds and catalog-service.js files in /src folder and expose the Product entity of the Northwind service for consumption.
6. Add the service URL as the credentials of the cds.requires entry of the Northwind service in package.json.
7. Open a new terminal and run cds watch.

Steps to store Product Data

1. Create schema.cds file in /db folder to expose the Products entity for data creation.
2. Create and Deploy the data model to a persistent DB as mentioned here. This creates a .db file in root. It also creates a cds.requires entry for the SQLite db in package.json.
3. Modify the catalog-service.js file to add the DB insert statements.
4. Open a new terminal and run cds watch.

References

1. https://blogs.sap.com/2020/05/26/cap-consume-external-service-part-1/
2. https://cap.cloud.sap/docs/get-started/in-a-nutshell#deploying-persistent-databases
3. https://cap.cloud.sap/docs/node.js/cds-connect#cdsconnectto--kindurl--service