How to combine multiple requests response nodejs?

user_17870144 0
Viewed 46

I have an array of data and need to fetch data for each item and combine them.

// This is inside a Nextjs async API route

const data = ['item1','item2','item3']

let result = []

data.forEach(async (item)=>{
const res = await fetch(`https://websitename.com/${item}`)
console.log(res)  //gives a valid data
result = [...result,...res]
}

console.log(result)  //gives an empty array

Here, it returns an empty array even though for each item data is being fetched. How to make such requests?

express node.js asynchronous api javascript
3 Answers

The answer you get is in json format. You must convert it before you can use it

const res = await fetch(`https://websitename.com/${item}`    
    const data = await res.json()
    console.log(data)

If this doesn't solve your problem, then it's probably more of an async thin , JS is not fill the array before you call it

user_181824220

Because you are executing the async function inside the loop where it only returns promise for each execution. In this case, You can use Promise.all()

const data = ['item1','item2','item3']

let requests = data.map(item => {
    return fetch(`https://websitename.com/${item}`);
};

Promise.all(requests).then((responses) => {

    // Reason of using flat is, You will get array of responses like [[res1], [res2], [res3]]
    // If you want to merge those together, You can use flat()
    const results = responses.flat();

    // do whatever you want with results

});

Read about using Async/Await in Array methods

user_84099220 
const data = ['item1','item2','item3']

let result = []

for(var i=0;i<data.length;i++){

    const res = await fetch(`https://websitename.com/${data[i]}`)
    console.log(res)  //gives a valid data
    result = [...result,...res]
}

console.log(result)
user_152524430
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