Benefiting from cds.context

bookshop/srv/admin-service.js

@@ -7,6 +7,6 @@ module.exports = cds.service.impl (function(){
 
 /** Generate primary keys for target entity in request */
 async function genid (req) {
-  const {ID} = await cds.tx(req).run (SELECT.one.from(req.target).columns('max(ID) as ID'))
+  const {ID} = await SELECT.one.from(req.target).columns('max(ID) as ID')
   req.data.ID = ID - ID % 100 + 100 + 1
 }

bookshop/srv/cat-service.js

@@ -1,15 +1,15 @@
 const cds = require('@sap/cds')
 const { Books } = cds.entities ('sap.capire.bookshop')
 
-class CatalogService extends cds.ApplicationService { async init(){
+class CatalogService extends cds.ApplicationService { init(){
 
   // Reduce stock of ordered books if available stock suffices
   this.on ('submitOrder', async req => {
-    const {book,amount} = req.data, tx = cds.tx(req)
-    let {stock} = await tx.read('stock').from(Books,book)
+    const {book,amount} = req.data
+    let {stock} = await SELECT('stock').from(Books,book)
     if (stock >= amount) {
-      await tx.update (Books,book).with ({ stock: stock -= amount })
-      this.emit ('OrderedBook', { book, amount, buyer:req.user.id })
+      await UPDATE (Books,book).with ({ stock: stock -= amount })
+      await this.emit ('OrderedBook', { book, amount, buyer:req.user.id })
       return { stock }
     }
     else return req.error (409,`${amount} exceeds stock for book #${book}`)

fiori/srv/mashup.js

@@ -20,7 +20,7 @@ module.exports = async()=>{ // called by server.js
   CatalogService.prepend (srv => srv.on ('READ', 'Books/reviews', (req) => {
     console.debug ('> delegating request to ReviewsService')
     const [id] = req.params, { columns, limit } = req.query.SELECT
-    return ReviewsService.tx(req).read ('Reviews',columns).limit(limit).where({subject:String(id)})
+    return ReviewsService.read ('Reviews',columns).limit(limit).where({subject:String(id)})
   }))
 
   //
@@ -28,8 +28,8 @@ module.exports = async()=>{ // called by server.js
   //
   CatalogService.on ('OrderedBook', async (msg) => {
     const { book, amount, buyer } = msg.data
-    const { title, price } = await db.tx(msg).read (Books, book, b => { b.title, b.price })
-    return OrdersService.tx(msg).create ('Orders').entries({
+    const { title, price } = await SELECT.from (Books, book, b => { b.title, b.price })
+    return OrdersService.create ('Orders').entries({
       OrderNo: 'Order at '+ (new Date).toLocaleString(),
       Items: [{ product:{ID:`${book}`}, title, price, amount }],
       buyer, createdBy: buyer
@@ -43,7 +43,6 @@ module.exports = async()=>{ // called by server.js
     console.debug ('> received:', msg.event, msg.data)
     const { subject, rating } = msg.data
     return UPDATE(Books,subject).with({rating})
-    // ^ Note: the framework will execute this and take care for db.tx
   })
 
   //

orders/srv/orders-service.js

@@ -8,18 +8,14 @@ class OrdersService extends cds.ApplicationService {
     this.before ('UPDATE', 'Orders', async function(req) {
       const { ID, Items } = req.data
       if (Items) for (let { product_ID, amount } of Items) {
-        const { amount:before } = await cds.tx(req).run (
-          SELECT.one.from (OrderItems, oi => oi.amount) .where ({up__ID:ID, product_ID})
-        )
-        if (amount != before) this.orderChanged (product_ID, amount-before)
+        const { amount:before } = await SELECT.one.from (OrderItems, oi => oi.amount) .where ({up__ID:ID, product_ID})
+        if (amount != before) await this.orderChanged (product_ID, amount-before)
       }
     })
 
     this.before ('DELETE', 'Orders', async function(req) {
       const { ID } = req.data
-      const Items = await cds.tx(req).run (
-        SELECT.from (OrderItems, oi => { oi.product_ID, oi.amount }) .where ({up__ID:ID})
-      )
+      const Items = await SELECT.from (OrderItems, oi => { oi.product_ID, oi.amount }) .where ({up__ID:ID})
       if (Items) for (let it of Items) this.orderChanged (it.product_ID, -it.amount)
     })
 

package.json

@@ -31,6 +31,9 @@
   "mocha": {
     "parallel": true
   },
+  "engines": {
+    "node": ">= 12.18"
+  },
   "jest": {
     "testEnvironment": "node"
   },

reviews/srv/reviews-service.js

@@ -1,5 +1,5 @@
 const cds = require ('@sap/cds')
-module.exports = cds.service.impl (async function(){
+module.exports = cds.service.impl (function(){
 
   // Get the CSN definition for Reviews from the db schema for sub-sequent queries
   // ( Note: we explicitly specify the namespace to support embedded reuse )
@@ -12,9 +12,7 @@ module.exports = cds.service.impl (async function(){
   // Emit an event to inform subscribers about new avg ratings for reviewed subjects
   this.after (['CREATE','UPDATE','DELETE'], 'Reviews', async function(_,req) {
     const {subject} = req.data
-    const {rating} = await cds.tx(req) .run (
-      SELECT.one (['round(avg(rating),2) as rating']) .from (Reviews) .where ({subject})
-    )
+    const {rating} = await SELECT.one (['round(avg(rating),2) as rating']) .from (Reviews) .where ({subject})
     global.it || console.log ('< emitting:', 'reviewed', { subject, rating })
     this.emit ('reviewed', { subject, rating })
   })
@@ -23,8 +21,7 @@ module.exports = cds.service.impl (async function(){
   this.on ('like', (req) => {
     if (!req.user)  return req.reject(400, 'You must be identified to like a review')
     const {review} = req.data, {user} = req
-    const tx = cds.tx(req)
-    return tx.run ([
+    return cds.run ([
       INSERT.into (Likes) .entries ({review_ID: review, user: user.id}),
       UPDATE (Reviews) .set({liked: {'+=': 1}}) .where({ID:review})
     ]).catch(() => req.reject(400, 'You already liked that review'))
@@ -34,9 +31,8 @@ module.exports = cds.service.impl (async function(){
   this.on ('unlike', async (req) => {
     if (!req.user)  return req.reject(400, 'You must be identified to remove a former like of yours')
     const {review} = req.data, {user} = req
-    const tx = cds.tx(req)
-    const affectedRows = await tx.run (DELETE.from (Likes) .where ({review_ID: review,user: user.id}))
-    if (affectedRows === 1)  return tx.run (UPDATE (Reviews) .set ({liked: {'-=': 1}}) .where ({ID:review}))
+    const affectedRows = await DELETE.from (Likes) .where ({review_ID: review,user: user.id})
+    if (affectedRows === 1)  return UPDATE (Reviews) .set ({liked: {'-=': 1}}) .where ({ID:review})
   })
 
 })