File Line Reader

Asynchronous line-by-line file reader.

Install

npm install file-line-reader

Usage

Use the constructor to create a LineReader object. Then use the function nextLine to receive the next line. The library will only load as many content of the file as necessary allowing to read very large files.

var LineReader = require('file-line-reader');

var reader = new LineReader('longfile.txt');

// Reads the file line of the longfile.txt file
reader.nextLine(function (err, line) {
    if (err) {
        // file not found, no read rights, ..
    }
    
    console.log(line);
});

Advanced Example

In this example we read the license file line by line with a 100ms delay between each log call.

var LineReader = require('file-line-reader');

var reader = new LineReader('LICENSE.txt');

function slowReader() {
    setTimeout(function() {
        reader.nextLine(function (err, line) {
            if (line !== null) {
                console.log(line);
                slowReader();
            }
        });
    }, 100);
}

slowReader();

License

MIT License.