promise-foreach

This is a simple implementation of foreach based on promises.

Works great in the browser with browserify.

$3

$ npm install promise-foreach

$3

###### Simple case
``javascript
const promiseForeach = require('promise-foreach')

const list = [{
firstName: 'John',
lastName: 'Doe'
}, {
firstName: 'Marie',
lastName: 'Doe'
}]

promiseForeach.each(list,
person => {
return ${person.firstName} ${person.lastName}
},
(arrResult, person) => {
return {
firstName: person.firstName,
lastName: person.lastName,
fullName: arrResult[0]
}
},
(err, newList) => {
if (err) {
console.error(err)
return ;
}
console.log('newList : ', newList)
})
`

###### Complex case
`javascript
const https = require('https');
const promiseForeach = require('promise-foreach')

const list = [{
firstName: 'John',
lastName: 'Doe',
photo_id: 1
}, {
firstName: 'Marie',
lastName: 'Doe',
photo_id: 2
}]

promiseForeach.each(list,
[
person => {
return ${person.firstName} ${person.lastName}
},
person => {
return asyncGetPhoto(person.photo_id)
}
],
(arrResult, person) => {
return {
firstName: person.firstName,
lastName: person.lastName,
fullName: arrResult[0],
photo: arrResult[1]
}
},
(err, newList) => {
if (err) {
console.error(err)
return ;
}
console.log('newList : ', newList)
})

function asyncGetPhoto(photo_id) {
return new Promise(function (resolve, reject) {
var request = https.get('https://jsonplaceholder.typicode.com/photos/' + photo_id, function (response) {
var body = []
response.on('data', function (chunk) {
body.push(chunk)
})
response.on('end', function () {
resolve(JSON.parse(body.join('')))
})
})
request.on('error', function (err) {
reject(err)
})
})
}
`

###### Concurrency case
`javascript
const https = require('https');
const promiseForeach = require('promise-foreach')

const list = [{
firstName: 'John',
lastName: 'Doe',
photo_id: 1,
comment_id: 3
}, {
firstName: 'Marie',
lastName: 'Doe',
photo_id: 2,
comment_id: 4
}]

promiseForeach.each(list,
[
person => {
return ${person.firstName} ${person.lastName}
},
person => {
return asyncGetPhoto(person.photo_id)
},
person => {
return asyncGetComment(person.comment_id)
}
],
(arrResult, person) => {
return {
firstName: person.firstName,
lastName: person.lastName,
fullName: arrResult[0],
photo: arrResult[1],
comment: arrResult[2]
}
},
(err, newList) => {
if (err) {
console.error(err)
return ;
}
console.log('newList : ', newList)
})

function asyncGetPhoto(photo_id) {
return new Promise(function (resolve, reject) {
var request = https.get('https://jsonplaceholder.typicode.com/photos/' + photo_id, function (response) {
var body = []
response.on('data', function (chunk) {
body.push(chunk)
})
response.on('end', function () {
setTimeout(function () {
resolve(JSON.parse(body.join('')))
}, 1000)
})
})
request.on('error', function (err) {
reject(err)
})
})
}
function asyncGetComment(comment_id) {
return new Promise(function (resolve, reject) {
var request = https.get('https://jsonplaceholder.typicode.com/comments/' + comment_id, function (response) {
var body = []
response.on('data', function (chunk) {
body.push(chunk)
})
response.on('end', function () {
resolve(JSON.parse(body.join('')))
})
})
request.on('error', function (err) {
reject(err)
})
})
}
`

###### Browser case
$ browserify -r promise-foreach > modules.js

`html



`

$3

To run the package's test, first install the dependencies, then run npm test:

`
$ npm install
$ npm test
``

$3

MIT License