Files
cloud-cap-samples/packages/bookshop/srv/admin-service.js
2019-12-16 21:50:23 +01:00

99 lines
3.4 KiB
JavaScript

const cds = require('@sap/cds')
// We are mashing up three services...
const admin = cds.connect.to ('AdminService')
const bupa = cds.connect.to('API_BUSINESS_PARTNER')
const db = cds.connect.to('db')
// Reflected entities for local database
const { Books, Addresses } = db.entities
// Fetch current user's addresses from S/4 for ValueHelp.
module.exports = (admin => {
admin.on ('READ', 'usersAddresses', async (req) => {
// const UsersAddresses = req.query.from (Addresses) .where ({ BusinessPartner: req.user.id })
// FIXME: Again that absolutely useless error message:
// [2019-12-16T20:30:14.106Z | ERROR | 1940862]: The server does not support the functionality required to fulfill the request
// FIXME: Even worse: click Orders Edit ->
// [2019-12-16T20:38:52.918Z | WARNING | 1575675]: Not Found
const { A_BusinessPartnerAddress:Addresses } = bupa.entities
const UsersAddresses = SELECT.from (Addresses, a => {
a.AddressID.as('ID'),
a.BusinessPartner,
a.Country.as('country'),
a.CityName.as('cityName'),
a.PostalCode.as('postalCode'),
a.StreetName.as('streetName'),
a.HouseNumber.as('houseNumber')
}) .where ({ BusinessPartner: req.user.id })
return bupa.transaction(req) .run (UsersAddresses) // TODO: I'd like to write .read instead of .run
})
})
// Replicate chosen addresses from S/4 when filing orders.
admin.before ('PATCH', 'Orders', async (req) => {
const ID = req.data.shippingAddress_ID; if (!ID) return //> something else
const address = await bupa.tx(req) .run (
SELECT.one.from(Addresses).where({
ID, BusinessPartner: req.user.id
})
)
if (address) return db.tx(req) .upsert (Addresses) .entries (address)
})
// Update local replicas when sources change in S/4.
bupa.on ('BusinessPartner/Changed', async (msg) => {
console.log('>> received:', msg.data)
const BusinessPartner = msg.data.KEY[0].BUSINESSPARTNER //> .KEY[0] >> revisit w/ Oliver
// fetch affected entries from local replicas
const local = db.transaction (msg)
const replicas = await local.read (Addresses) .where ({BusinessPartner})
// skip if not affected
if (replicas.length === 0) return
// fetch changed data from S/4 -> might be less than local due to deletes
const changed = await bupa.tx(msg).read (Addresses) .where ({
BusinessPartner, ID: replicas.map(a => a.ID) // where in
})
// update local replicas with changes from remote
return local.run (changed.map (a =>
UPDATE (Addresses) .with(a) .where ({ ID: a.ID })
))
})
// Validate incoming orders and reduce books' stocks.
admin.before ('CREATE', 'Orders', async (req) => {
const { Items } = req.data
// validate input...
if (!Items || Items.length === 0)
return req.reject ('Please order at least one item.')
if (!req.data.shippingAddress_ID) return req.reject (
'Please enter a valid shpping address.',
'shippingAddress_ID'
)
// reduce stock on ordered books...
const all = await db.tx(req) .run (Items.map (each =>
UPDATE (Books) .set ('stock -=', each.amount)
.where ('ID =', each.book_ID) .and ('stock >=', each.amount)
))
all.forEach ((affectedRows,i) => affectedRows > 0 || req.error (409,
`${Items[i].amount} exceeds stock for book #${Items[i].book_ID}`
))
})
// eslint-disable-next-line no-unused-vars
function _diff (a,b) {
let any, diff={}
for (let each in b) if (b[each] !== a[each]) diff[each] = b[any=each]
return any && diff
}