I am working on something that needs nested foreach loops in order to process some data.
Intention is there is an array of ID's I need to look up, each ID related to a user and I just need to extract their names from the response of an API call. Service A has the list of ID's and then sends a HTTP GET request to service B for each ID (can't change this), which then responds with the correct info in the format of
{
success: true,
user: {
name: 'John Doe'
}
}
Code that doesn't work but is my current code
incidents.forEach((name) => {
foo = {
nameID: names
}
const asyncForEach = async (array, callback) => {
for(let index = 0; index < array.length; index++) {
await callback(array[index], index, array)
}
}
const startMulti = async () => {
await asyncForEach(foo.nameID, async (obj, index) => {
await userController.userInfo(obj)
.then((userInfo) => {
foo.nameID[index] = userInfo.user.name
})
.then(() => {
foobarArray.push(foo)
})
})
return res.json({success: true, foobar: foobarArray})
}
startMulti()
})
Took the origional idea of nested foreach loops from this blog post which allowed me to do another before though this one won't work
https://codeburst.io/javascript-async-await-with-foreach-b6ba62bbf404
edit show variables
let foo let foobarArray = []
Added await to usercontroller now getting proper output but error message saying Cannot set headers after they are sent to the client
Names is coming from outside the code and is just needed where it is. Not sure how to explain it without explaining the project in whole/detail.
edit show code for usercontroller.userinfo
exports.userInfo = function(id) {
return new Promise((resolve, reject) => {
let user = {
_id: id
}
options.json = {user}
request.get('/userInfo', options, (err, response, body) => {
resolve(body)
})
})
}
This code work perfectly as expected - ie it sends request with proper payload and returns proper response.
Edit current code attempt
let foobarArray =[]
let names = []
let foo
for (const incident of incidents) {
foo = {
nameID: names
}
for (const id of incident.names) {
const userInfo = await userController.userInfo(id)
names.push(userInfo.user.name)
}
}
return res.json({success: true, fooreturned: foobarArray})
Error message caused by await in front of userController
SyntaxError: await is only valid in async function
edit attempt at making async function (I normally don't use async/await instead use promises)
Even after attempt code below it still gives the error message above - I had tried same code before I edited to show error message
exports.userInfo = async function(id) {
return new Promise((resolve, reject) => {
let user = {
_id: id
}
options.json = {user}
request.get('/userInfo', options, (err, response, body) => {
resolve(body)
})
})
}
Full code below except the userInfo function above which already is shown above.
exports.monitor = function(req, res, next) {
const fooID = req.params.id
let foobarArray =[]
let names = []
let foo
Incident.find({fooID})
.exec((err, incidents) => {
if(err) {
console.log(err)
return res.json({success: false, foobar: []})
}
if(incidents != []) {
for (const incident of incidents) {
foo = {
nameID: incident.foo[0].names
}
for (const id of foo.responded) {
const userInfo = await userController.userInfo(id)
names.push(userInfo.user.name)
}
}
return res.json({success: true, foobar: foobarArray})
}
})
}
That's pretty much the whole code except some logging lines I still have to add. I pretty much need the foobar: foobarArray to be an array of objects - foo - where nameID is the array of proper names not ID's. The proper names are fetched via the userController.userInfo where the ID is passed.
edit - New code after async and promisify - not sure I did the promisify correctly
exports.monitor = async function(req, res, next) {
const fooID = req.params.id
const incidents = await userController.incidentFind(fooID)
}
exports.incidentFind = async function(id) {
return new Promise((resolve, reject) => {
const sevenAgo = moment().subtract(7, 'days').toISOString()
let alertArray =[]
let names = []
let alert
Incident.find({monitorID, createdAt: {$gte: sevenAgo}})
.exec((err, incidents) => {
if(err) {
console.log(err)
return res.json({success: false, foobar: []})
}
if(incidents != []) {
for (const incident of incidents) {
foo = {
nameID: incident.foo[0].names
}
for (const id of foo.responded) {
const userInfo = await userController.userInfo(id)
names.push(userInfo.user.name)
}
}
return res.json({success: true, foobar: foobarArray})
}
})
})
}
Not sure what the actual controller monitor should contain. Bit lost
Error message
/home/me/Projects/app/incidents/controllers/users.js:100
const userInfo = await userController.userInfo(id)
^^^^^
SyntaxError: await is only valid in async function
Looks like the function should be async already (put async before function name).
