Files
cloud-cap-samples/packages/bookstore/srv/services.js
2019-09-23 13:32:14 +02:00

35 lines
1.0 KiB
JavaScript

const cds = require('@sap/cds')
module.exports = async (srv) => {
const { Books } = srv.entities
// Check all amounts against stock before activating
srv.before(['CREATE', 'UPDATE'], 'Orders', (req) => {
const tx = cds.transaction(req), order = req.data
return Promise.all(order.Items.map(each => tx.run(
UPDATE(Books).where({ ID: each.book_ID })
.and(`stock >=`, each.amount)
.set(`stock -=`, each.amount)
).then(affectedRows => {
if (!affectedRows) {
req.error(409, `${each.amount} exceeds stock for book #${each.book_ID}`)
}
})))
})
const reviews_srv = await cds.connect.to('sap.capire.reviews.ReviewsService')
// react on event messages from reviews service
reviews_srv.on('reviewed', (msg) => {
console.debug('> received', msg)
})
// delegate requests to reviews service
srv.on('READ', 'Reviews', async (req) => {
const { Reviews } = reviews_srv.entities
const tx = reviews_srv.transaction(req)
const results = await tx.read(Reviews)
return results
})
}