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Promises/Fetch in JavaScript: how to extract text from text file

I'm working on a small program in JavaScript. Basically, I want to use Promise and fetch to extract text out of two text files. However, I can't figure out how to get the actual text out of the files. Here's my current code.

sample.txt

this is
a sample
text file.

sample2.txt

this is
the second
sample file.

index.js

function getSampleText() {

  Promise.all([
  fetch('sample.txt'),
  fetch('sample2.txt')
  ]).then(allResp => {
    let sampleResp = allResp[0];
    let sample2Resp = allResp[1];
    console.log(sampleResp);
    console.log(sample2Resp);
  })
}

Here are the Promises...how do I get the text out of these?

Promises

like image 609
Leia_Organa Avatar asked May 17 '18 22:05

Leia_Organa


1 Answers

Fetch doesn't return a promise for the text of a response - it returns a promise for a Response object available after headers have been received.

This is so you can do cool things like:

  • Determine how you want to read the body of the response based on the headers.
  • Stream the response progressively etc.

If you want the text of the response - you can .text() the Response objects to get a promise for that:

Promise.all([
  fetch('sample.txt').then(x => x.text()),
  fetch('sample2.txt').then(x => x.text())
]).then(([sampleResp, sample2Resp]) => {
  console.log(sampleResp);
  console.log(sample2Resp);
});
like image 71
Benjamin Gruenbaum Avatar answered Sep 17 '22 23:09

Benjamin Gruenbaum