Book 4.2 figure 4.4 consume PurchaseOrders: Error >> 502

[mata-r]

Error when consuming the PurchaseOrder Error

request: {
      method: 'GET',
      url: '/A_PurchaseOrder?$top=1000&$orderby=PurchaseOrder%20asc&$select=PurchaseOrder,PurchaseOrderType,Supplier,SupplierPhoneNumber',
      headers: {
        accept: 'application/json,text/plain',
        'accept-language': 'en-US,en;q=0.6',
        apikey: 'CFfHtCWzvP1dz5AP06VeRaNafoXRH8HI'
      }
    },
    correlationId: '185607af-113b-4f85-b0ba-5bd0302084a5'
  }
}
[cds] - Error: Error during request to remote service: 
Cannot find module '@sap-cloud-sdk/http-client'

[mata-r]

I couldn't find it in the book but I installed the missing module and then the service worked instead of throwing a 502 error
npm install @sap-cloud-sdk/http-client