Text file to JSON, last few lines are not included in the result

Question

I'm reading a text file and converting it to JSON format using regex in my react project.It is working fine but not including last 20-30 lines of the text file. There is some problem while converting it to JSON but I am unable to understand the problem.

Here is my code:

    readTextFile = file => {
        let rawFile = new XMLHttpRequest();
        rawFile.open("GET", file, false);
        rawFile.onreadystatechange = () => {
            if (rawFile.readyState === 4) {
                if (rawFile.status === 200 || rawFile.status === 0) {
                    let allText = rawFile.responseText;
                    // console.log(allText)

                    let reg = /\d\d\d\d-(0?[1-9]|1[0-2])-(0?[1-9]|[12][0-9]|3[01]) (00|[0-9]|1[0-9]|2[0-3]):([0-9]|[0-5][0-9]):([0-9]|[0-5][0-9])/g;

                    let arr = [];
                    let start = null;
                    let line, lastSpacePos;
                    let match;
                    while ((match = reg.exec(allText)) != null) {
                        if(start) {
                            line = allText.slice(start, match.index).trim();
                            lastSpacePos = line.lastIndexOf(' ');
                            arr.push({
                                date: line.slice(0, 19),
                                text: line.slice(20, lastSpacePos).trim(),
                                user_id: line.slice(lastSpacePos).trim()
                            });
                        }

                        start = match.index
                    }
                    console.log(arr);

                    this.setState({
                        // text: JSON.stringify(arr)
                        text: allText
                    });
                }
            }
        };

Answer 1

Am not certain about the issue with the existing code at Question.

To get expected result described at Question utilizing an alternative approach you can use RegExp /\s{2,}|\n+/g to replace space characters greater than 2 and new line characters; /[\d-]+\s[\d:]+/g to get dates; /.+(?=\s\w+\s$|\s\w+$)|\w+\s$|\w+$/g to match text that is followed by space, word characters and space character or end of string and characters before space characters followed by word characters and space character or end of string; return an object with a property set for each element of the array from .map()

let allText = `2014-06-01 23:07:58 President Resigns in Georgia’s Breakaway Region of 
Abkhazia t.co/DAploRvCvV                                                    nytimes 
2014-06-01 23:48:06 The NYT FlipBoard guide to understanding climate 
change and its consequences t.co/uPGTuYiSmQ                                 nytimes 
2014-06-01 23:59:06 For all the struggles that young college grads 
face, a four-year degree has probably never been more valuable 
t.co/Gjf6wrwMsS         nytimes 
2014-06-01 23:35:09 It's better to be a community-college graduate than 
a college dropout t.co/k3CO7ClmIG                                           nytimes 
2014-06-01 22:47:04 Share your experience with Veterans Affairs health 
care t.co/PrDhLC20Bt                                                        nytimes 
2014-06-01 22:03:27 Abandon Hope, Almost All Ye Who Enter the N.B.A. 
Playoffs t.co/IQAJ5XNddR                                                    nytimes`;

// replace more than one consecutive space character and new line characters
allText = allText.replace(/\s{2,}|\n+/g, " ");
// get dates
let dates = allText.match(/[\d-]+\s[\d:]+/g);
// get characters that are not dates
// spread `dates` to resulting array
// return object
let res = allText
.split(/[\d-]+\s[\d:]+\s/)
.filter(Boolean)
.map((text, index) => 
  [dates[index], ...text.match(/.+(?=\s\w+\s$|\s\w+$)|\w+\s$|\w+$/g)])
.map(([date, text, user_id]) => ({date, text, user_id}));

console.log(res);