How to read a text file and return it as a JSON object in Node JS?

Question

I have a text file. I need to read the file inside a function and return it as a JSON object. The following is throwing an error "Unexpected token V in JSON at position 0" .

Server.js

fs.readfile('result.txt', 'utf8', function(err,data) {
    if(err) throw err;
    obj = JSON.parse(data);
    console.log(obj);
});

result.txt looks like the following

VO1: 10 5 2

VO2: 5 3 2

I think I cannot use JSON.parse directly. How do I proceed?

You can't, since the `.txt` file gets imported as a string, iirc. You'll have to write your own parser for the data to be translated to json. — roberrrt-s, Sep 12 '16 at 13:10

score 4 · Accepted Answer · edited Jun 20 '20 at 09:12

4

Assuming the following:

Every line is separated by a newline character (\n)

Every line is separated by a : where the part in front of it is the key and the part behind it is a (space) separated string that should indicate the keys values as an array.

Below should work for your format:

fs.readfile('result.txt', 'utf8', function(err,data) {
    if(err) throw err;
    let obj = {};
    let splitted = data.toString().split("\n");
    for (let i = 0; i<splitted.length; i++) {
        let splitLine = splitted[i].split(":");
        obj[splitLine[0]] = splitLine[1].trim();
    }
    console.log(obj);
});

edited Jun 20 '20 at 09:12

Community

1
1

answered Sep 12 '16 at 13:18

baao

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I am getting an error with splitLine as unidentified identifier. – Bharg Sep 13 '16 at 09:18
So some of the lines don't have a key, a value or a `:`. Try to add a check before you assign the values to the object @Bharg – baao Sep 13 '16 at 09:19

score 2 · Answer 2 · edited May 21 '22 at 10:15

2

It could be issue with UTF-8 string format, Tried below code and it works

const resultBuffer = fs.readFileSync('result.txt');
const resultData = JSON.parse(resultBuffer.toString().trim());

edited May 21 '22 at 10:15

Tyler2P

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answered May 21 '22 at 06:59

Praveen

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It’s an issue with the file *not being JSON* or even remotely like JSON. – Quentin May 21 '22 at 07:01
My text file was JSON and this creates a valid JSON object of that text file. – darx May 26 '22 at 12:55

Seth Eden · Answer 3 · 2018-02-09T14:22:58.993

0

Thanks to Baao for providing that answer.

As another flavor of solution, if you don't have any ":" for perhaps a list of files you could always code in a key like so:

var data = fs.readFileSync(pathAndFilename);
var testData = {};
var splitList = data.toString().split('\r\n');
for (var i = 0; i < splitList.length; i++) {
     testData['fileNumber' + i.toString()] = splitList[i];
}

edited Feb 09 '18 at 14:22

answered Feb 09 '18 at 13:56

Seth Eden

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Hello, what is the pathAndFilename value? – Amanda Koster Jul 23 '21 at 22:49
This would be the full path and file name to the file that you want to read. aka C:\Program Files\MyApp\Configuration\systemConfiguration.txt – Seth Eden Sep 01 '21 at 15:29

score -1 · Answer 4 · answered Sep 12 '16 at 13:19

-1

You need to parse the text file by yourself. You can use RegExp or some other means to extract the values, create an object out of that and then JSON.stringify it.

answered Sep 12 '16 at 13:19

Vincent Schöttke

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score -1 · Answer 5 · answered Sep 19 '21 at 08:20

-1

improving upon @baao answer:

const fs = require("fs")

fs.readFile('.czrc', 'utf8', function (err, data) {
    if (err) {
        console.error(err)
        throw "unable to read .czrc file.";
    }
   const obj = JSON.parse(data)
});

answered Sep 19 '21 at 08:20

Nikhil Nayyar

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score -2 · Answer 6 · answered Sep 12 '16 at 13:15

-2

Your result.txt is not valid json.

Valid json would look like this.

{
  "VO1": [10, 5, 2],
  "VO2": [5, 3, 2]
}

answered Sep 12 '16 at 13:15

kenda

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How to read a text file and return it as a JSON object in Node JS?

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