AshanthaLahiru

'use strict';

module.exports.hello = (event, context, callback) => {
  const response = {
    statusCode: 200,
    body: JSON.stringify({
      message: 'Go Serverless v1.0! Your function executed successfully!',
      input: event,
    }),
  };

AshanthaLahiru

# Welcome to Serverless!
#
# This file is the main config file for your service.
# It's very minimal at this point and uses default values.
# You can always add more config options for more control.
# We've included some commented out config examples here.
# Just uncomment any of them to get that config option.
#
# For full config options, check the docs:
#    docs.serverless.com

AshanthaLahiru

let promise = (time) => {
    return new Promise((res, rej) => {
        console.log(`Promise ${time} start`)
        setTimeout(() => {
            res(`Promise ${time} end`)
        }, time)
    })
}

AshanthaLahiru

promise(1000)                   // |-----|
    .then(msg => {
        console.log(msg)
    })
promise(2000)                   // |-----|-----|
    .then(msg => {
        console.log(msg)
    })
promise(3000)                   // |-----|-----|-----|
    .then(msg => {

AshanthaLahiru

promise(1000)                   // |-----|
    .then((msg) => {
        console.log(msg)
        return promise(2000)    //       |-----|-----|
    })
    .then((msg) => {
        console.log(msg)        
        return promise(3000)    //                   |-----|-----|-----|
    })
    .then((msg) => {

AshanthaLahiru

Promise.all([promise(1000), promise(2000), promise(3000)])
    .then((msgs) => {
        msgs.forEach(msg => {
            console.log(msg)
        });
        console.log(`End of Promise.all(..)`)
    })

//Result
/* 

AshanthaLahiru

let tryAsync = async () => {
    let p1 = promise(1000)                   // |-----|
    let p2 = promise(2000)                   // |-----|-----|
    let p3 = promise(3000)                   // |-----|-----|-----|

    console.log(await p1)
    console.log(await p2)
    console.log(await p3) 
}

AshanthaLahiru

let tryAsync = async () => {
    console.log(await promise(1000))                   // |-----|
    console.log(await promise(2000))                   //       |-----|-----|
    console.log(await promise(3000))                   //                   |-----|-----|-----|   
}

tryAsync()

//Result
/* 

AshanthaLahiru

let tryAsync = async () => {
    let msgs = await Promise.all([promise(1000), promise(2000), promise(3000)])
    msgs.forEach(msg => {
        console.log(msg)
    });
    console.log(`End of Promise.all(..)`)
}
tryAsync()

//Result

AshanthaLahiru

service: HelloService
provider:
  name: aws
  runtime: nodejs6.10
functions:
  hello:
    handler: handler.hello
    events:
      - http:
          path: hello/welcome