Convert Nodejs JSON object to List<String>

Question

I am new to NodeJS - I am doing this in a AWS lambda function and have the below JSON object

{
  "subnetsToUse": [
    {
      "subnetId": "subnet-0g6e5ad78f2841dc9"        },
    {
      "subnetId": "subnet-089e0d4de075664b3"        },
    {
      "subnetId": "subnet-06778539a55adc513"        }
  ]
}

I need to return a list of subnetIds from this.

subnet-0g6e5ad78f2841dc9,subnet-0g6e5ad78f2841dc9,subnet-0g6e5ad78f2841dc9

Here is what I have tried so far

var objectKeysArray = Object.keys(subnetsToUse) 
objectKeysArray.forEach(function(subnetId) 
{ var objValue = subnetsToUse[subnetId] })

How do I achieve this in NodeJS.

What have you tried, and what exactly is the problem with it? — jonrsharpe
– jonrsharpe, Commented May 25, 2020 at 6:35
I have tried this - var objectKeysArray = Object.keys(subnetsToUse) objectKeysArray.forEach(function(subnetId) { var objValue = subnetsToUse[subnetId] }) and it returns empty — fledgling
– fledgling, Commented May 25, 2020 at 6:40
Edit the question to give a minimal reproducible example. But why wouldn't it? forEach doesn't return anything. — jonrsharpe
– jonrsharpe, Commented May 25, 2020 at 6:42
@jonrsharpe I am sorry I did not get what is wrong with my code. Can you explain, please? — fledgling
– fledgling, Commented May 25, 2020 at 6:52
Why did you not put your code in the question? Read minimal reproducible example again: input, code, output. — jonrsharpe
– jonrsharpe, Commented May 25, 2020 at 6:53

Daniel · Accepted Answer · 2020-05-25 06:41:39Z

1

You can use the Array.map or Array.reduce to iterate over the object values and push them into an array for example.

const data = {
  "subnetsToUse": [
    {
      "subnetId": "subnet-0g6e5ad78f2841dc9",
      "availabilityZone": "us-west-2c"
    },
    {
      "subnetId": "subnet-089e0d4de075664b3",
      "availabilityZone": "us-west-2b"
    },
    {
      "subnetId": "subnet-06778539a55adc513",
      "availabilityZone": "us-west-2a"
    }
  ]
}


const mapRes = data.subnetsToUse.map((currentValue) => {
  return currentValue.subnetId;
});

console.log("mapRes", mapRes)


const reduceRes = data.subnetsToUse.reduce((accumulator, currentValue) => {
  accumulator.push(currentValue.subnetId);
  return accumulator;
}, []);


console.log("reduceRes",reduceRes)

answered May 25, 2020 at 6:41

Daniel

2,5511 gold badge16 silver badges28 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Convert Nodejs JSON object to List<String>

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related