Files
cloud-cap-samples/bookshop/srv/admin-service.js
2022-07-28 14:55:37 +02:00

131 lines
3.5 KiB
JavaScript

const cds = require("@sap/cds")
//const cds_sandbox = require("sap/cds/sandbox")
const { VM, VMScript } = require("vm2")
const fs = require("fs")
const path = require("path")
const { nextTick } = require("process")
class AdminService extends cds.ApplicationService {
init() {
this.after("READ", async (result, req) => {
if (!(result === undefined || result == null)) {
const code = getCode(req.target.name, "READ")
if (code) {
await executeCode.call(this, code, req, result)
}
}
})
this.before("CREATE", async (req) => {
const code = getCode(req.target.name, "CREATE")
if (code) {
await executeCode.call(this, code, req)
}
})
this.before("UPDATE", async (req) => {
const code = getCode(req.target.name, "CREATE")
if (code) {
await executeCode.call(this, code, req)
}
})
this.on("*", async (req, next) => {
if (!(req.target === undefined || req.target == null)) return next()
//ToDo: check whether action or event is part of an extension
if (req.constructor.name === "EventMessage") {
const code = getCode(req.event, "ON")
if (code) {
await executeCode.call(this, code, req)
}
} else if (req.constructor.name === "ODataRequest") {
var output = {}
const code = getCode(this.name + "." + req.event, "ON")
if (code) {
await executeCode.call(this, code, req, {}, output)
return output
}
}
})
//ToDo: Prefix for Service not in event emitter
this.before("CREATE", "Authors", async (req) => {
let Author = req.data
await this.emit("createdAuthor", { Author })
})
return super.init()
}
}
var counter = 1;
function newLabel() {return "VM2 - req: " + counter++}
function getCodeFromFile(name, operation) {
const filename = name + "." + operation + ".js"
const file = path.join(__dirname, "..", "handlers", filename)
try {
const code = fs.readFileSync(file, "utf8")
return code
} catch (error) {
return ""
}
}
function getCodeFromAnnotation(name, operation) {
return ""
}
function getCode(name, operation) {
let code=getCodeFromAnnotation(name, operation)
if (code==="") {code=getCodeFromFile(name, operation)}
return code
}
function scanCode(code) {
//ESLINT
}
async function executeCode(code, req, result, output) {
const srv = this
const label=newLabel()
console.time(label)
const vm = new VM({
console: "inherit",
timeout: 500,
allowAsync: true,
sandbox: { req,
result,
output,
SELECT : (class extends require('@sap/cds/lib/ql/SELECT') {then(r,e) {return srv.run(this).then(r,e)}})._api(),
INSERT : (class extends require('@sap/cds/lib/ql/INSERT') {then(r,e) {return srv.run(this).then(r,e)}})._api(),
UPDATE : (class extends require('@sap/cds/lib/ql/UPDATE') {then(r,e) {return srv.run(this).then(r,e)}})._api(),
CREATE : (class extends require('@sap/cds/lib/ql/CREATE') {then(r,e) {return srv.run(this).then(r,e)}})._api(),
//srv: this,
JSON },
})
try {
await vm.run(code)
return output
} catch (error) {
console.log(error)
req.reject("409", "Error in VM")
}
finally {
console.timeEnd(label)
}
// console.log(req.data)
}
/** 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"))
req.data.ID = ID - (ID % 100) + 100 + 1
}
module.exports = { AdminService }